Methods and Systems for HARQ Protocols Related Applications This application claims the benefit of U.S. Provisional Patent Application No. 61/046,625 filed on April 21, 2008 and U.S. Provisional Patent Application No. 61/050,329 filed on May 5, 2008, which are hereby incorporated by reference in their entirety. Field of the Invention The invention relates to wireless communication Systems. Background of the Invention Various wireless access technologies have been proposed or implemented to enable mobile stations to perform Communications with other mobile stations or with wired terminals coupled to wired networks- Examples of wireless access technologies include GSM (Global System for Mobile Communications) and UMTS (universal Mobile Telecommunications System) technologies, defined by the Third Generation Partnership Project (3GPP); and CDMA 2000 (Code Division Multiple Access 2 000) technologies, defined by 3GPP2. As part of the continuing evolution of wireless access technologies to improve spectral efficiency, to Improve services, to lower costs, and so forth, new standards have been proposed. One such new Standard is the Long Term Evolution (LTE) Standard from 3GPP, which seeks to enhance the UMTS wireless network. The CDMA 2000 wireless access technology from 3GPP2 is also evolving. The evolution of CDMA 2000 is referred to as the Ultra Mobile Broadband (ÜMB) access technology, which supports significantly higher rates and reduced latencies- Another type of wireless access technology is the WiMAX (Worldwide Interoperability for Microvave Access) technology. WiMAX is based on the IEEE (Institute of Electrical and Electronics Engineers) 802.16 Standard. The WiMAX wireless access technology is designed to provide wireless broadband access. A few variations of hybrid automatic repeat request (HARQ) transmission/operation schemes exist in the above identified access technologies. One variation is nicest HARQ in which each encoded packet includes data from one user. This can be fully asynchronous in which case the modulation and coding scheme (MCS), transmission time (slot/frame) and resource allocation are independent for each transmission of an encoded packet (first and all re-transmissions). Assignment signaling is used to describe the resource allocation, MCS and user IDs for each transmission and re-transmission. While this approach allows adaptation to real time channel conditions, it incurs large signaling overhead. Uncials HARQ can alternatively be fully synchronous. in this case, the MCS scheme for transmissions (first and all retransmissions) is the same, resource allocation (location) remains the same for first and all retransmissions (the transmission location rust be the same as the first transmission). The transmission interval is fixed, and assignment signaling is required only for the first transmission. This enables lower signaling overhead for retransmission, but can cause significant scheduling complexity and signaling overhead for the first transmission due to the irregular vacancies of resources that occurs since some resources need to be reserved for retransmissions that may not be necessary. Another HARQ variant is multicast HARQ in which each encoded packet includes data for multiple users. The worst channel quality indicators (CQIs) among multiple users retransmitted if one or more users could not decode it successfully, even though some of the users may have successfully decoded the packet. Multi-cast HARQ can be 5 implemented using fully asynchronous and fully synchronous schemes, Summary of the Invention According to a first aspect of the invention, there is provided a method comprising: for a HARQ process, the HARQ process comprising a first transmission of an encoder packet and at least one retransmission, in which a transmission resource for each respective transmission is allocated; transmitting control Information from a base station to a mobile station for each respective transmission/ the control information comprising: information to uniquely identify the HARQ process; and an Identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the transmission. In sore amendments, transmitting information to 20 uniquely identify the HARQ process includes transmitting one of: an encoder packet identifier (ID) to uniquely identify the encoder packet; and a resource identifier (ID) of a previous transmission. In some embroilments, transmitting control information 25 for the first transmission also comprises one or more of: a modulation and coding scheme (MCS) for the encoder packet; a MIMO mode used for transmitting the encoder packet; and one or more other pieces of control information relevant to the HARQ transmission of the encoder packet. In some embodiments, transmitting control information further comprises: scrambling the control information using a user identifier (ID) associated with the mobile station. In some embodiments, for allocating a transgression resource for at least one nicest Uplink (UL) transmission, transmitting control Information' comprises: transmitting a UL control segment that is a portion of a DL transmission resource, the UL control segment comprising a portion that identifies a location in the UL control segment for transmitting nicest control information for each at least one nicest UL transmission and a portion that defines the control information for use in transmitting the nicest UL 10 transmission. In some embodiments, for allocating a transmission resource for at least one uncials Downlink (DL) transmission, transmitting control information comprises: for each at least one uncials DL transmission, transmitting a DL uncials control 15 and traffic segment comprising a portion of the DL nicest control and traffic segment that defines the control information for use in transmitting the uncials DL transmission and a portion of the DL uncials control and traffic segment for transmitting data for the respective uncials DL transmission. According to a second aspect of the invention, there is provided a method for acknowledging a DL HARQ transmission comprising: receiving an encoder packet; if the encoder packet is successfully decoded, transmitting an acknowledgement (ACK); if the encoder packet is not successfully decoded, transmitting a negative acknowledgement (NAK); if no retransmission is received within a predetermined time period of transmitting the NAK, transmitting a NULL indicating that no control information signaling pertaining to the retransmission has been received. According to a third aspect of the invention, there is provided a method for acknowledging a DL HARQ transmission comprising: if an acknowledgement (ACK) in response to a previously transmitted encoder packet has been received, not retransmitting an encoder packet; if a negative acknowledgement (NAK) in response to a previously transmitted encoder packet has been received, retransmitting a sub-packet Of the encoder packet; if a NULL is received indicating that no control Information signaling has been received by a sender of the 5 NULL regarding a previously transmitted encoder packet, retransmitting at least a sub-packet of the encoder packet. In some embodiments, retransmitting at least a sub" packet of the encoder packet if a NULL is received comprises: if the NULL is received in response to a previously transmitted sub-packet of an encoder packet that is a first sub-packet transmission, retransmitting the first sub-packet transmission, the first sub-packet transmission comprising control Information signaling sent in a first sub-packet transmission; if the NULL is received in response to a previously transmitted sub-packet of an encoder packet that is a subsequent sub-packet transmission to a first sub-packet transmission, retransmitting the subsequent sub-packet transmission, the subsequent sub-packet transmission comprising control Information signaling that comprises: Information to uniquely identify the HAP.Q proces3; and an Identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the subsequent sub-packet transmission. In some embodiments, retransmitting control Information signaling to uniquely identify the HARQ process 25 includes transmitting one of: an encoder packet identifier (ID) to uniquely identify the encoder packet; and a resource identifier (ID) of a previous transmission. In some embodiments, retransmitting control Information signaling sent in the first sub-packet transmission 30 comprises: Information to uniquely identify the HARQ process; an Identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the transmission; and one or more of: a modulation and coding scheme (MCS) for the encoder packet; a MIMO mode used for transmitting the encoder packet; and one or more other pieces of control information relevant to the HARQ transmission of the encoder packet. According to a fourth aspect of the invention, there is provided a method for rescheduling a ÜL HARQ transmission comprising: if an encoder packet is not successfully decoded, scheduling an uL transmission of a sub-packet at a predeterinined time interval; and transmitting control .10 information pertaining to the UL transmission according to the first aspect of the invention described above. According to a fifth aspect of the invention, there is provided a method of error recovery for a ÜL HARQ transmission comprising: if a NuLL is received in response to a previously transmitted sub-packet of an encoder packet that is a first sub-packet transmission; dynamically scheduling a retransraission of the first sub-packet transmission at any time; retransmitting the first sub-packet transmission, the first sub-packet transmission comprising control information signaling sent in a first sub-packet transmission; if a NULL is received in response to a previously transmitted sub-packet of an encoder packet that is a subsequent sub-packet transmission to a first siob-packet transmission; scheduling a retransmission of the first sub-packet transmission at a predetermined time; retransmitting the subsequent sub-packet transmission, the subsequent sub-packet transmission comprising control signaling information that comprises: information to uniquely identify the HARQ process; and an Identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the stibsequent sub-packet transmission. According to a sixth aspect of the invention, there is provided a method comprising: in a system having a known HARQ aclcnowledgement (ACK) delay, retransmit delay and number of HARQ interlaces, which are each defined in configuration signaling sent to a mobile station and which are a function of at least one of a time division depleting downlink/uplink (TDD DL/UL) ratio and a frequency division d-placing downlink/uplink (FDD DL/OL) ratio, at a base station, determining the timing for receiving an ACK/NAK forgo a mobile station based on configuration signaling in response to a previously sent transmission of an encoder packet by the base station; and at a 10 mobile station, determining the timing for receiving one of a transmission and a retransmission of a sub-packet of an encoder packet from a base station based on the configuration signaling in response to a previously sent NAK by the mobile station. In some embodiments, the HARQ acknowledgement (ACK) delay, retransmission delay and number of HARQ interlaces, which are each defined in configuration signaling sent to a mobile station are a function of portioning of legacy and non-legacy transmission resources- In some embodiments, a non-legacy transmission resource is a transmission source supported by at least one of: IEEE802.16m, WiMAX evolution and LTE advanced. In some embodiments, the ACK/NAK and the transmission and retransmissions can be transmitted on one of: a time 25 resource, a frequency resource, and a time and frequency resource. In some embodiments, if the TDD DL/ÜL ratio of sub-frames of a frame are asymmetries; the UL ACKs for corresponding DL transmissions, in which the DL transmissions occur in more 30 DL sub-frames of the frame than UL sub-frames that are available© for the UL ACKs, transmitting a plurality of UL ACKs in one ÜL sub-frame; the DL ACKs for corresponding ÜL transmissions, in which the UL transmissions occur in more UL sub-frames of the frame than DL sub-frames that are available for the DL ACKs, transmitting a plurality of DL ACKs in one DL sub-frame. In some embodiments, if the FDD DL/UL ratio of sub-5 frames of a frame are asymmetric; the UL ACKs for corresponding DL transmissions, in which the DL transmissions occur in more DL sub-frames of the fare than UL sub-frames that are available for the UL ACKs, transmitting a plurality of ÜL ACKs in one ÜL sub-frame; the DL ACKs for corresponding UL 10 transmissions, in which the UL transmissions occur in more UL sub-frames of the frame than DL sub-frames that are available for the DL ACKs, trginsmlting a plurality of DL ACKs in one DL sub-frame. Other aspects and features of the present invention 15 will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. Brief Description of the Drawings Embodiments of the invention will now be described with reference to the attached drawings in which: Figure 1 is a block diagram of a cellular communication system on which embodiments of the invention may be implemented; Figure 2 is a schematic diagram of a transmission resource used for sub-frame control signaling according to an embodiment of the invention; Figures 3A to 3E are example schematic diagrams of radio frame having downlink (DL) and uplink (UL) portions for 30 DL transmissions and ÜL acknowledgements for a HARQ scheme according to an embodiment of the invention; Figures 4A to 4C are example schematic diagrams of radio frame having downlink (DL) and uplink (DL) portions fox UL transmissions and DL acknowledgements for a HARQ scheme according to an embodiment of the invention; Figure 5 is a schematic diagram of an example of a resource availability bitmap in which group and nicest allocations can coexist according to an embodiment of the invention; Figure 6A is a schematic diagram of a conventional 10 packet preparation; Figure 6B is a schematic diagram of a packet preparation process for superposition of a packet for use in interference cancellation according to an embodiment of the invention; Figure 7 is a schematic diagram for a system in which a packet preparation process is used for superposition of a packet according to an embodiment of the invention; Figure 8 is a schematic diagram of sub-carriers of two adjacent carriers that are not aligned due to the spacing 20 of the respective carriers; Figure 9 is a schematic diagram of an example of two adjacent carriers in which each carrier supports both legacy and non-legacy sub-frames in a transmission resource according to an embodiment of the invention; Figure 10 is a schematic diagram of an example of two adjacent carriers in which one carrier supports legacy transmissions and the other carrier supports non-legacy transmissions according to an embodiment of the invention; Figure 11 is a schematic diagram of an example of two 30 adjacent carriers in which one carrier supports both legacy and non-legacy sub-frames in a transmission resource and the other carrier supports only non-legacy sub-frames in the transmission resource according to an embodiment of the invention; Figures 12A and 12B are schematic diagrams of an example of two adjacent carriers in which both carriers support 5 non-legacy transmissions according to an embodiment of the invention; Figures 13A and 13B are schematic diagrams of an example of two adjacent carriers in which both carriers support non-legacy transmissions according to another embodiment of the 10 invention; Figure 13C is a schematic diagram of an example of multiple adjacent carriers in which each of the carriers support non-legacy transmissions according to an embodiment of the invention; Figure 14 is a schematic diagram of an example of two adjacent carriers in which one carrier supports legacy transmissions and the other carrier supports non-legacy transmissions according to an embodiment of the invention; Figure 15 is a block diagram of an example base station that might be used to implement some embodiments of the present invention; Figure 16 is a block diagram of an example wireless terminal that might be used to implement some embodiments of the present invention; figure 17 is a block diagram of a logical breakdown of an example OFDM transmitter architecture that might be used to implement some embodiments of the present invention; Figure 18 is a block diagram of a logical breakdown of an example OFDM receiver architecture that might be used to 30 implement some embodiments of the present invention; Figure 19 is a flow chart of an example method according to an embodiment of the invention; Figure 20 is a flow chart of an example method according to another embodiment of the invention; Figure 21 is a flow chart of an example method according to yet another embodiment of the invention; Figure 22 is a flow chart of an example method according to a further embodiment of the invention; Figure 23 is a flow chart of an example method 10 according to another embodiment of the invention; Figure 24 is a flow chart of an example method according to a further embodiment of the invention; and Figure 25 is a flow chart of an example method according to yet another embodiment of the invention. Detailed Description of the Embodiments of the Invention For the purpose of providing context for embodiments of the invention for use in a communication system, Figure 1 shows a base station controller (BSC) 10 which controls wireless Communications within multiple cells 12, which cells are served by corresponding base stations (BS) 14. in general, each base station 14 facilitates Communications using OFDM with mobile and/or wireless terminals 16, which are within the cell 12 associated with the corresponding base station 14. The mobile terminals 16 may be referred to as users or UE in the description that follows. The individual cells may have multiple sectors (not shown). The movement of the mobile terminals 16 in relation to the base stations 14 results in significant fluctuation in channel conditions- As illustrated, the base stations 14 and mobile terminals 16 may include multiple antennas to provide spatial diversity for Communications. Methods of transmission described herein may be performed for one or both of uplink (UL) and downlink (DL). UL 5 is transmitting in a direction from a mobile station to a base station. DL is transmitting in a direction from the base station to the mobile station. HARQ Protocol and Timing for Ireless Systems The TGm SRO (IEEE 802.l6m-07/002r4> specifies the following requirements: in section 6.2-1 pertaining to Data latency, Table 3 defines a maximum allowable latency for DL and UL of l0ms; and in section 6.10 pertaining to System overhead it is defined that "Overhead, including overhead for control 15 signaling as well as overhead related to bearer data transfer, for all applications shall be reduced as far as feasible without compromising overall performance and ensuring proper support of Systems features". Aspects of the invention provide a HARQ scheme to 20 address aspects of the above replacements- However, while aspects of the invention may be described in regard to IEEB802.16m, it is to be understood that embodiments of the invention are not limited to IBEE802.16m. Some embodiments of the invention may be applied to other communication standards 25 as well, such as, but not limited to WiMAX evolution and LTE advanced. Described herein are embodiments for use with HARQ schemes. Some embodiments of the invention involve a resource adaptive HARQ (RAS-HARQ) scheme, in particular control 30 signaling for the PAS-HARQ scheme- RAS-BARQ provides a trade-off between signaling overhead and flexibility in resource multiplexing among users. In some embodiments of the invention, specific control Information is signaled from a base station to a mobile station to enable RAS-HARQ operation. In some erabodiments of the invention, retransmission signaling in included as part of regular nicest signaling used 5 for both first transmission and retranstnisons. Synchronous HARQ has the benefit of minimum signaling overhead as retransraission does not need to be signaled, but the drawback of Inflexible resource allocation and multiplexing. If the mobile station misses the control 10 signaling of first sub-packet and base station does not recognize that, it is not possible to recover the packet. In case of ACK to NAK error in the DL for UL transmission, mobile station's retransmission may collide with other mobile stations. Asynchronous HARQ has the benefit of being flexible in terms of prioritization new transmission vs. retransmission. Therefore, it provides better link adaptation/time diversity performance for very low speed cases. If the mobile station misses the control signaling of the first or any other sub- 20 packet, there is still possibility to recover the packet. However, it has the drawback of requiring more signaling overhead compared to other schemes in order to indicate such parameters as HARQ channel identifiers (ACID), sub-packet identifiers (ID), HARQ identifier sequence number (AI-SN). RAS-HARQ has the benefit Of relatively small signaling overhead compared to the asynchronous HARQ and flexible resource allocation and multiplexing among users. However, it has the drawback of if the mobile station misses the control signaling of first transmission and the base 30 station does not recognize that, it Is not possible to recover the packet. There are several ways to perform retransmission in terms of the retransmission time interval, the resource locality fox: the retransmission and the MCS used for the retransmission. Table 1 briefly summarizes characteristics of 5 retransmission for Synchronous HARQ, Asynchronous HARQ and RAS-HARQ. Table 1 - Characteristics of retransmission for synchronous HARQ, Asynchronous HARQ and Resource Adaptive Synchronous HARQ Error in control signaling impacts HARQ performance since control information sent from the base station to the mobile station contains critical information for HARQ sub-packet combining. Two of the common techniques of recombining sub-packets include Chase combining and Incremental Redundancy (IR). In the case of Chase combining, each retransmission includes the same information. In the case of IR, each retransmission contains different information than the previous one, such that every retransmission provides a receiver with additional Information. IR provides both soft combining gain as well as coding gain. In some embodiments of the invention additional 5 signaling overhead typicality occurring when IR is used is avoided by defining a sub-packet format lookup table- For each MCS entry, the sub-packet format, i.e. modulation and effective coding rate derived from a mother code, is specified for each retransmission trial. Some entries in the lookup table can be 10 effectively reduced to Chase combining when two consecutive retransmission trials have the same sub-packet format. In some embodiments of the invention, a 3-state acknowledgement channel and associated error recovery operation enables the base station and mobile station to recover from 15 control signaling error and reduce packet loss. While Asynchronous EARQ typically requires more signaling overhead than other types of HARQ schemes, it allows more resource multiplexing flexibility at the base station. Asynchronous HARQ also allows the base station to perform error 20 recovery processes when needed. In some embodiments of the invention, RAS-RARQ may be used in combination with asynchronous HARQ. HARQ acknowledgment and retransmission timing is at least in part dependent on processing delay at the base station and at the mobile station. Time division duplex (TDD) downlink (DL) to uplink (uL) ratios and the location of DL sub-frames and ÜL sub-frames being assigned for transmission also affect the HARQ timing as the TDD DL to UL ratios rapist when the DL and UL resources are available for retransmission and 30 acknowledgement. In some embodiments of the invention, methods are provided that enable self deducible HARQ timing at the mobile station based on the use of HARQ related parameters configured by the base station. In Ras-HARQ, only the resource location needs to be signaled for retransmissions- In some embodiments, there are 5 multiple parallel HARQ processes in progress for the saitie mobile station, where each HARQ process corresponds to a first transmission and any retransmissions that are necessitated of an encoder packet. Therefore, retransmission signaling according to RAS-HARQ involves uniquely identifying a HARQ 10 process as well as a resource assigned for the retransmission. A first inaner of signaling a retransmission involves transacting signaling Information that includes an encoder packet ID to uniquely identify the encoder packet, and consequently the HARQ process, and resource assignment 15 Information for the retransmission. In some embodiments the signaling Information is scrambled as a function of a user ID of the mobile station involved in the retransmission. In some embodiments, with regard to a packet that is feeing subsequently retransmitted consistent with the first manner described above, signaling Information for the initial transmission of that packet includes a packet ID and resource assignment Information for the initial transmission. In some embodiments a user ID is also used for scrambling. In addition, other signaling Information that is transmitted for the initial transmission may include one or more of: the MCS; MIMO mode; and other characteristics that define the packet transmission, A second manner of signaling a retransmission involves transmitting signaling Information that includes a 30 resource ID of a previous retransmission and resource assignment Information for the retransmission. The use of the resource ID of the previous retransmission can uniquely identify the HARQ process since each HARQ process is assigned a different resource in the previous retransroission In some ernbodiments the signaling Information is scrambled as a function of a user ID of- the mobile station involved in the retransmission. In some ernbodiments, with regard to a packet that is being subsequently retransmitted consistent with the second manner described above, signaling information for the initial transmission of that packet includes a resource ID of the previous retransmission and resource assignment information for 10 the initial transmission. In some ernbodiments a user ID is also used for scrambling. In addition, other signaling information that is transmitted for the initial transmission may include one or more of: the MCS; MIMO made; and other characteristics that define the packet transmission With reference to Figure 19, a method will now be described that encompasses both the first and second manner described above. The method involves, for a HARQ process,. the HARQ process having a first transmission of an encoder packet and at least one retransmission, a step 19-1 of transmitting control information from a base station to a mobile station for each respective transmission. The control information includes information to uniquely identify the HARQ process and an Identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the transmission, In some ernbodiments, the step of transmitting information to uniquely identify the HARQ process includes transmitting one of: an encoder packet identifier (ID) to uniquely identify the encoder packet; and a resource identifier 30 (ID) of a previous transmission. Some examples of sub-frame control structures are presented in PCT patent application PCT/2008/001986 filed November 7, 2008 and U.S. Patent Application No. 12/202,741 filed September 2, 2008, both of which are assigned to the assignee of the present application, and are hereby incorporated by reference in their entirety. An example of RAS-HARQ will now be described with 5. reference to Figure 2. Figure illustrates at least part of a time resource, frequency resource, or time-frequency resource 200, used as a DL resource which is partitioned into multiple time-frequency segments 210,220,230,240,250. Segment 210 is a UL Control Segment (ÜCS) used for assigning resources for ÜL 10 traffic. Each of segments 220,230,240,250 are DL Unicast Control and Traffic Segments used for assigning a particular DL unicast resource and the resources used for the DL traffic for a respective mobile station. An expanded view of segment 210 includes a portion of 15 segment 210 for a uL Combination Index 212 and multiple portions 214,216,218 of the segment 212 for unicast control Information for each UL resource assignment- In some embodiments, the unicast control Information includes retransmission control Information that is used for signaling a 20 retransmission in accordance with the first manner of signaling described above. In some embodiments, the unicast control Information includes retransmission control Information that is used for signaling a retransmission in accordance with the second manner of signaling described above-An expanded view of segment 220 includes a portion of segment 220 for a DL Unicast Assignment Message 222 and a portion 224 of the segment 222 for the unicast transmission. In some embodiments, the DL Unicast Assignment Message 222 includes retransmission control Information that is used for signaling a retransmission in accordance with the first manner of signaling described above. In some embodiments, the DL Unicast Assignment Message 222 includes retransmission control information that is used for signaling a retransmission in accordance with the second manner of signaling described above. DL ünicast Control and Traffic Segments 230, 240 and 250 include similar portions as segment 220 described above for 5 different DL unicast assignments. Referring to the general method described above in Figure 19, in some embodiments, allocating a transmission resource for at least one unicast Uplink (UL) transmission, transmitting control information includes a step of transmitting a ÜL control segment that is a portion of & DL transmission resource, the ÜL control segment comprising a portion that identifies a location in the UL control segment for transmitting unicast control information for each at least one unicast UL transmission and a portion that defines the control information for use in transmitting the unicast UL transmission. Referring to the general method described above in Figure 19, in some embodiments, allocating a. transmission resource for at least one unicast Downlink (DL) transmission, transmitting control information comprises: for each at least one unicast DL transmission, transmitting a DL unicast control and traffic segment comprising a portion of the DL unicast control and traffic segment that defines the control information for use in transmitting the unicast DL transmission and a portion of the DL unicast control and traffic segment for transmitting data for the respective unicast DL transmission. In some embodiments of the invention, a 3-state ACK channel (ACKCH) is used as part of the RAS-HARQ scheme. A first state used on the channel is an ^'ACK", which indicates 30 correct reception of a packet, A second state is a "NAK", which is used to indicate failure in reception of a packet. A third state is a "NULL", in which no signal is transported by a mobile station on the ACKCH. A NULL occurs when the mobile station fails to detect the control signaling information corresponding to a sub-packet transmission. The following example describes an implementation of the 3-state ACKCH operating from the perspective of a mobile 5 station for DL. The mobile station sends an ACK to the base station when the mobile station succeeds in decoding a received packet. The mobile station sends a NAK to the base station when the mobile station fails to decode a received packet-10 After sending a NAK, the mobile station waits for a retransmission from the base station. If the mobile station does not receive any retransmission signaling within a predetermined time interval, the mobile station sends a NULL indicating that no retransmission signal was received. There are different possibilities why the mobile station may not have received any retransmission signaling. A first possibility is that the mobile station failed to detect the retransmission signaling from the base station. This may be overcome by the base station detecting the NuLL from the mobile station and the base station retransmitting the retransmission signaling. A second possibility is that the base station did not send a retransmission due to a NAK-to-ACK detection error at the base station. This may occur when the base station incorrectly detects an ACK when a NAK was sent by the mobile station, In this case, a packet failure will likely occur. In some implementations, the mobile station retains the HARQ buffer corresponding to an encoder packet until the expiry of a configurable timeout period. The following describes an implementation of the 3-state ACKCH operating from the perspective of a base station for DL. When the base station receives an ACK from a mobile station, the base station does not perform retransmission to the mobile station. In some implementations, as discussed above/ this may result in no retransmission being sent when the 5 base station incorrectly detects an ACK, when a NAK was sent by the mobile station, When the base station receives a NAK from the mobile station, the base station retransmits a sub-packet to the mobile station at a predetermined time interval. A new 10 resource assignment and encoded packet ID, and possible a user ID is signaled as described above-when the base station receives a NuLL from a mobile station, the base station will interpret that the mobile station has lost the signaling associated with a sub-packet 15 transmission. If the transmission that was sent was a first sub-packet transmission, the base station will retransmit the first sub-packet in conjunction with the full signaling Information, i.e. MCS, resource location, user ID, MIMO information, packet 20 ID etc. The base station can dynaraically schedule the retransmission of this first sub-packet at any time. If the transmission that was sent was a second or subsequent sub-packet transmission, the base station will retransmit at a predetermined time interval the corresponding sub-packet. In some embodiments, for the first manner of retransmitting signaling described above, the base station sends the encoded packet ID, resource location information for the current retransmission sub-packet and user ID. In some embodiments, for the second manner of retransmitting signaling described above, the base station sends the original resource location of the first sub-packet, resource location information of the current retransmission sub-packet, and the user ID (for scrarabling). Referring to Figure 20, a method will now be described for acknowledging a DL HARQ transmission. A first step 20-1 of the method involves receiving an encoder packet. A second step 20-2 involves, if the encoder packet is 5 successfully decoded, transmitting an acknowledgement (ACK). A third step 20-3 involves, if the encoder packet is not successfully decoded, transmitting a negative acknowledgement (NAK). A fourth step 20-4 involves, if no retransmission is received within a predetermined time period of transmitting the 10 NAK, transmitting a NÜLL indicating that no control information signaling pertaining to the retransmission bas been received, The following describes an impleraentation of the S-state ACKCH operating from the perspective of a base station for UL. When the base station fails to receive a packet, it schedules an ÜL retransmission of the sub-packet at the predetermined time interval, in scheduling the ÜL retransmission the base station sends a new resource assignraent, a HARQ process Identification or an encoded packed Identification and user ID to the mobile station. When the base station succeeds in decoding a packet, no retransmission is scheduled. In some embodiments, the base station performs an error recovery procedure for the case when the mobile station 25 fails to decode the first sub-packet transmission signaling or the subsequent retransmission signaling. An example of an error recovery procedure is described below. For the case of first sub-packet transmission signaling, if the base station fails to detect any UL 30 transmission from the mobile station at the assigned resource, the base station can resend the full signaling Information, i.e. MCS, resource location, user ID (scrambled), MIMO Information etc. In some embodiments the base station dynamically schedules the retransmission o£ this first sub-packet at any time. For the case of retransmission signaling, i-e. second 5 or subsequent sub-packet retransmissions, if the base station fails to detect any UL transmission forte the mobile station at the assigned resource, the base station can send at the predetermined time interval a reduced amount of signaling Information, in comparison to the signaling Information sent for the first transmission. For the first manner of retransmission signaling described above, the base station sends the encoded packet ID, resource assignment for the current retransmission sub-packet and user ID. For the second manner of retransmission signaling described above, the base station sends the original resource assignment of the first sub-packet, resource assignment of the next retransmission sub-packet and user ID. Referring to Figure 21, a method will now be described for acknowledging a DL HARQ transmission. A first step 21-1 of the method involves, if an acknowledgement (ACK) in response to a previously transmitted encoder packet has been received, not retransmitting an encoder packet. A second step 21-2 of the method involves, if a negative acknowledgement (NAK) in response to a previously transmitted encoder packet has been received, retransmitting a sub-packet of the encoder packet. A third step 21-of the method involves, if a WULL is received indicating that no control Information signaling has been received by a sender of the NULL regarding a previously transmitted encoder packet, retransmitting at least a sub- packet of the encoder packet. In some embodiments, if the NuLL is received in response to a previously transmitted sub-packet of an encoder packet that is a first sub-packet transmission, retransmitting the first sub-packet transmission, the first sub-packet transmission comprising control information signaling sent in a first sub-packet transmission. In some embodiments, if the NULL is received in S response to a previously transmitted sub-packet of an encoder packet that is a subsequent s\ab-packet transmission to a first sub-packet transmission, retransmitting the subsequent sub-packet transmission. The subsequent sub-packet transmission may include control information signaling such as information 10 to uniquely identify the HARQ process and an' identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the subsequent sub-packet transmission. Referring to Figure 22, a method will now be 15 described for rescheduling a UL HARQ transmission. A first step 22-1 of the method involves, if an encoder packet is not successfully decoded, scheduling an UL transmission of a sub-packet at a predetermined time interval. A second step 22-2 involves transmitting control information pertaining to the UL 20 transmission according to the method described above with regard to Figure 19. Referring to Figure 23, a method wig now be described for error recovery for a UL HARQ transmission. A first step 23-1 of the method involves, if a NÜLL is received in response to a previously transmitted sub-packet of an encoder packet that is a first sub-packet transmission, dynamically scheduling a retransmission of the first sub-packet transmission at any time. A second step 23-2 involves retranslating the first sub-packet transmission, the first sub-packet transmission comprising control information signaling sent in a first sub-packet transmission. A third step 23-3 involves, if a NULL is received in response to a previously transmitted sub-packet of an encoder packet that is a subsequent sub-packet transgression to a first sub-packet transmission, scheduling a retransmission of the first sub-packet transmission at a predetermined time- A fourth step 23-4 involves, retransmitting the subsequent sub-5 packet transmission. The subsequent sub-packet transmission includes control signaling information that includes information to uniquely identify the HARQ process and an identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the 10 subsequent sub-packet transmission. The following describes an implementation of the 3-state ACKCH operating from the perspective of a mobile station for UL. When the mobile station receives the retransmission 15 signaling from the base station, the mobile station transacts the corresponding sub-packet in the assigned resource. In some implementations, the mobile station retains the HARQ buffer corresponding to an encoded packet until the expiry of a configurable timeout period. Deducible DL HARQ Timing The HARQ protocol timing should be flexible to adapt to different TDD DL/UL ratio and non-legacy (one example of which is iEEE802.16m) / legacy partitioning, without incurring unnecessary overhead, The minimum HARQ hOK delay and Retranslate (Retry) delay and the number of HARQ channels/interlaces are defined in system/mobile station configuration signaling which corresponds to particular partitioning of resources used in legacy and non-legacy systems, and TDD DL/UL ratios. With these parameters defined, the precise HARQ timing for ACK/NAK transmission and retransmission can be deduced as will be described below with reference to Figures 3A to 3E. This concept can be applied to bQth TDD and frequency division depleting (FDD)- In some embodiments, due to the asymmetrical DL/UL TDD (or FDD) ratio, the UL ACK of DL HARQ for multiple DL sub-5 frames may coincide in one ÜL sub-frame as shown in Figures 3A to 3E. The location of the ACKCH of a mobile station within the UL sub-frame can be deduced forgo the HARQ interlace number, the a3Signed DL resource of the previous HARQ sub-packet transmission, and the number of UL ACKCHs allocated per DL sub-10 , frames as signaled in a super frame header. In some embodiments, a similar approach is used for the case of DL acknowledgement of UL HARQ as shown in Figures 4A to 4C. Several examples will now be described to illustrator different implementations based on different TDD DL/UL ratios, 15 ACK delay, retranslate delay and HARQ interlaces. Figure 3A illustrates two successive 5itis radio frames 310,320 that each include 8 sub-frames- Four sub-frames 311,312,313,314 are a portion of the first radio frame 310 used for DL transmission and retransmission. Sub-frames 311 and 312 are for use with legacy equipment and sub-frames 313 and 314 are for use with equipment that supports IEEB802.16m. Four sub-frames 321,322,323,324 are a portion of a subsequent 5ms radio frame 320 used for DL transmission and retransmission. Sub-frames 321 and 322 are for use with legacy equipment and sub-frames 323 and 324 are for use with equipment supports IEEE802.16m. Sub-frames 313 and 323 are a first HARQ interlace "A" and sub-frames 314 and 324 are a second HARQ interlace "B". Four Sub-frames 315,316,317,318 are a portion of the first 5ms radio frame 310 used for UL acknowledgement (ACK). 30 Sub-frame 315 is for use with legacy equipment and sub-frames 316, 317 and 318 are for use with equipment that supports IEEE802.16m. Four sub-frames 325,326,327,328 are a portion of the Subsequent radio frame 320 used for UL ACK. Sub-frame 325 is fox use with legacy equipment and sub-frames 326, 327 and 328 are for use with equipment that Supports IEEE802.16m. As there are two sub-frames allocated for IEEE802.16m DL transmission and retransmission and three sub-frames 5 allocated for UL ACKs, the TDD DL/UL ratio is 2:3. The ACK delay, which is a delay between a transmission or retransmission at the base station and an ACK being transmitted by the mobile station, is illustrated to be four sub-frames in the example of Figure 3A. The Retransmit 10 delay, which is a delay between the ACK being transmitted at the mobile station and the retransmission being transmitted by the base station, is illustrated to be four sub-frames in the example of Figure 3A. Figure 3A is an example having a particular set of 15 parameters, i.e. TDD DL/UL ratio, ACK delay, Retransmit delay and HARQ interlace, 5ms radio frame and 8 sub-frames per radio frame. It is to be understood that more generally these parameters are implementation specific and are not intended to limit the invention to a specific embodiment; Additional 20 examples that follow below illustrate the use of different values for some of the parameters. Furthermore, while only two radio frames are illustrated in Figure 3A, the figure is exemplary of operation of the timing scheme and as such the illustration of only two frames is not intend to limit the 25 invention to what is described with reference to only this particular example- In addition, the sub-frames are described as supporting legacy and lEEE802.16m specifically, but it is to be understood that more generally the sub-frames may support legacy and non-legacy transmissions. Figure 3B illustrates two successive 5ms radio frames 330,340 and a DL transmission portion of a third radio frame 350 in which in each frame, five sub-frames are used for DL transmission and retransmission and three sub-frames are used for ÜL ACK. DL transmission sub-frames 331 and 332 of the first frame 330 are for use with legacy equipment and DL transgression sub-frames 333, 334 and 335 of the first frame 330 are for use with equipment that supports IEEE802,16m. DL 5 transmission sub-frames 341 and 342 of the second frame 340 are for use with legacy equipment and DL transmission sub-frames 343, 344 and 345 of the second frame 340 are for use with equipment that supports IEEE802.16m. DL transmission sub-frames 351 and 352 of the third frame 350 are for use with 10 legacy equipment and DL transmission sub-friaries 353, 354 and 355 of the third frame 350 are for use with equipment that is compliant with IEEE802.16m. UL transmission sub-frames 336 of the first frame 330 is for use with legacy equipment and UL transmission sub-frames 33T and 338 of the first frame 330 are for use with equipment that supports IEEE802.16m. UL transmission sub-frame 346 of the second frame 340 is for use with legacy equipment and UL transmission sub-frames 347, including sub-divided portions 347A and 347B, and 348 of the second frame 340 are for use with equipment that is compliant with IEEE802.16m. As there are three sub-frames allocated for ISEE802.1€m DL transmission and retransmission and two s\ib-frames allocated for ÜL ACKs, the TDD DL/UL ratio is 3:2. In Figure 3B there are 4 HARQ interlaces, sub-frames 25 333, 344 and 354 is a first interlace "A", sub-frames 334 and 345 are a second interlace "B", sub-frames 335 and 352 are a third interlace "C" and sub-frames 343 and 353 are a fourth interlace '"D". The ACK delay and the Retransmit delay are each 30 illustrated to be four sub-frames in the example of Figure 3B. In Figure 3B, the sub-frame location within the radio frames for ACK and retransmission of a HARQ interlace change over time to accoranodate the minimum ACK delay and Retransmit delay and retain the same ordering of the HARQ interlaces. For example, the ordering of the retransmissions in the allocated sub-frames is tiaintained in the pattern "ABCD" as can be seen 5 from A(sub-farina 333), B(sub-frame 334), C(sub-frame 335), D(sub-frame 343), A(sub-frame 344), B(sub-frame 345), C(sub-frame 352), D (sub-frame 353), A(sub-farina 355). The ordering of the ACKs in the allocated sub-frames is similarly maintained as ^ABCD" as A(sub-frame 337), B(sub-frame 338), C(sub-fare 10 347A), D(sub-frame 347B), A{sub-frame 348). As can be seen in Figure 3B, the UL ACK in 347A and 347B for interlaces C and D, respectively, share a single sub-frame. Figure 3C illustrates an example hitch has a similar 8 sub-frame per frame Sms radio frame, five sub-frame/three sub-frame per frame partition for DL transmissions and UL ACKs, four sub-frame ACK delay, 4 sub-frame Retransmit delay, and TDD DL/UL ratio of 3:2 as illustrated in Figure 3B. In Figure 3C the sub-frame location within a radio frame for ACK and retransmission of a HARQ interlace change over time to accommodate the minimum ACK delay and retransmission delay. However, the ordering of the HARQ interlaces can change over time. For example, the ordering of the retransmissions in the allocated sub-frames is '^ABCABDCAB" as seen by A (sub-frame 363), B(sub-frarae 364), C(sub-frame 365), A(sub-frame 373), B(sub-frame 374), D(sub-frame 375), C(sub-frame 383), A(sub-frame 384), B(sub-frame385). The ordering of the ACKs in the allocated sub-frames follows that of the transmitted pattern in the form A(sub-frame 367), B(sub-frame 368), C(sub-frame 377A), A(sub-frame 377B), B(sub-frame 378). As can be seen in Figure 3C, the UL ACK in 377A and 377B for interlaces C and A, respectively, share a single sub-frame. Figure 3D illustrates an example which has a similar 8 sub-frame per frame Sras radio frame, five sub-frame/three sub-frame per frame partition for DL transmissions and UL ACKs, four sub-frame ACK delay, 4 sub-frame Ketransrait; delay, and TDD PL/UL ratio of 3:2 as illustrated in Figure 3B. In Figure 3D the sub-frame location within a radio 5 frame for ACK and retransitlission of a HARQ interlace is fixed. For example, the ordering of the retransmissions in the ailocated sub-frames has the pattern "ABCABD" as shown by A(sub-frame 393), B(sub-frame 394), C(sub-frame 395), A{sub-frame 403), B(sub-frame 404), D(sub-frame 405), A(sub-frame 413), B(sub-frame 414), C(sub-frame 415). The ordering of the ACKs in the ailocated sub-frames is A(sub-frame 397), B(sub-frame 398), A(3ub-frame 407), C(sub.-frame 408A), B(sub-frame 408B), A(sub-frame 417), D(sub-frame 418A), B(sub-frame 418B). As can be seen in Figure 3D, the UL ACK in 408A and 408B for interlaces C and B, respectively, share a single sub-frame and in 418A and 41SB for interlaces D and B, respectively, share a single sub-frame. Figure 3E illustrates three successive 5ms radio frames 500,510,520 in which in each frame, five sub-frames are used for DL transmission and retransmission and three sub-frames are used for UL ACK. All of the DL transmission sub-frames in each of the frames are for use with equipment that supports IEEE802.16m. All of the ÜL transmission sub-frames in each of the frames are for use with equipment that supports 25 lEEE802.16m. As there are five sub-frames allocated for IEEE802.16m DL transmission and retransmission and three sub-frames allocated for UL ACKs, the TDD DL/UL ratio is 5:3. In Figure 3E there are 7 HARQ interlaces, sub-frames 30 501, 513 and 525 is a first interlace "A", sub-frames 502 and 514 are a second interlace "B", sub-frames 503 and 515 are a third interlace "C", sub-frames 504 and 521 are a fourth interlace "D", sub-frames 505 and 522 are a fifth interlace "E", sub-frames 511 and 523 are a sixth interlace "F" and sub-frames 512 and 524 are a seventh interlace "G". The ACK delay and the Retransmit delay are each illustrated to be four sub-frames in the example of Figure 3B. In Figure 3E, the sub-frame location within a radio frame for ACK and retransmission of a HARQ interlace change over time to accommodate the minimum ACK delay and retransmission delay and retain the same ordering of the HARQ interlaces. For example, the ordering of the retransmissions in the allocated sub-frames is "ABCDEFG" in the form A(sub-frame 501), B(sub-frame 502), C(sub-frame 503), D(sub-fare 504), E(sub-frame 505), F(sub-frame 511), G(sub-frame 512), A{sub-frame 513), B(sub-frame 514), C(sub-frame 515), D(sub-frame 521), E(sub-frame 522), F(sub-fare 523), G(sub-frame 15 524), A(sub-frame 525). The ordering of the ACKs in the allocated sub-frames is A(sub-frame 506A), B(sub-frame 506B), C(sub-frame 507), D(sub-frame 508), E(sub-frame 516A), F(sub-frame 516B), G(sub-frame 516C), A(sub-frame 517), B(sub-frame 518), C(sub-frame 526A), D(sub-frame 526B), E(sub-frame 526C), 20 F(sub-frame 527), G(s\ib-frame 528). As can be seen in Figure 3E, the ÜL ACK in506A and 506B for interlaces A and B, respectively, share a single sub-frame, in 516A, 516B and 516C for interlaces E, F and G, respectively, share a single sub-frame and in 526A, 526B and 526C for Interlaces C, D and E, 25 respectively, share a single sub-frame. Deducible UL HARQ Timing The minimum HARQ ACK and Retransmit delay and the number of HARQ channels are defined in system broadcast signaling which corresponds to particular partitioning of 30 legacy and IEE£8 02.16ra, and TDD DL/UL ratios. With these parameters defined, the precise HARQ timing can be deduced. This concept can be applied to both TDD and FDD. Figure 4A illustrates two successive 5ms radio frames 420,430 that echo include 8 sub-frames. Three sub-frames 421,422,423 are a portion of the first radios frame 420 used for UL transmission and retransraission. Sub-frame 421 is for use 5 with legacy equipment and sub-frames 422 and 423 arts for use with equipment that supports IEEE802.16m. Three sub-frames 431/432,433 are a portion of a subsequent 5ms radio frame 430 used for UL transmission and retransroission. Sub-frame 431 is for use with legacy equipment and sub-frames 432 and 433 are 10 for use with equipment that supports IEEE802.16ro. Sub-frames 422 and 432 are a first ÖARQ interlace "A" and sub-frames 423 and 433 are a second HARQ interlace "B". sub-frames 424,425,426,427,428 are a portion of the first 5ms radio frame 420 used for DL acknowledgement (ACK). Sub-frames 424 and 425 are for use with legacy equipment and sub-frames 426, 427 and 428 are for use with equipment that supports IEEE802.16m. Five sub-^frames 434,435,436,437,438 are a portion of the subsequent radio frame 430 used for DL ACK- Sub-frames 434,435 are for use with legacy equipment and sub-frames 435, 437 and 438 are for use with equipment that supports IBEE802.16m. As there are two sub-frames allocated for IEEE802.16ni UL transmission and retransmission and three sub-frames allocated for DL ACKs, the TDD DL/UL ratio is 3:2. The ACK delay is illustrated to be four sub-frames and the Retransmit delay is also illustrated to be four sub- frames in the example of Figure 4A. Figure 4B illustrates two successive 5ms radio frames 440,450 and a DL transmission portion of a third radio frame 30 460 in which in each frame, four sub-frames are used for DL transmission and retransmission and four sub-frames are used for UL ACK. UL transmission sub-frame 441 of the first frame 440 is for use with legacy equipment and UL transmission sub-frames 442, 443 and 444 of the first frame 440 are for use with equipment that supports IEEE802.l6m. UL transmission sub-frame 451 of the second. frame 450 is for use with legacy equipment and ÜL transmission sub-frames 452, 453 and 454 of the second 5 frame 450 are for use with equipment that supports IEEE802.16m. UL transmission sub-frame 461 of the third frame 460 is for use with legacy equipment and DL transmission sub-frames 462, 463 and 464 of the third frame 4 60 are for use with equipment that supports rEEE802.16m. DL ACK sub-frames 445 and 446 of the first frame 440 are for use with legacy equipment and DL ACK sub-frames 447, including sub-divided portions 447A and 447B, and 448 of the first frame 440 are for use with equipment that supports IEEE802.16m. DL ACK sub-frames 455 and 456 of the second frame 15 450 are for use with legacy equipment and UL transmission sub-frames 457, including sub-divided portions 457A and 457B, and 458 of the second frame 450 are for use with equipment that supports IEEE802.16m. As there are three sub-frames allocated for 20 IEEE802.16m ÜL transmission and retransmission and two sub-frames allocated for DL ACKs, the TDD DL/UL ratio is 2:3. In Figure 4B there are 4 HARQ interlaces, sub-frames 442, 453 and 464 is a first interlace ''A", sub-frames 443 and 454 are a second interlace "B", sub-frames 444 and 462 are a 25 third interlace "C and sub-frames 452 and 463 are a fourth interlace "*D". The ACK delay and the Retransmit delay are each illustrated to be four sub-frames in the earplug of Figure 4B. In Figure 4B, the sub-frame location within a radio 30 frame for ACK and retransmission of a HARQ interlace change over time to accomraodate the minimum ACK delay and Retransmit delay and retain the same ordering of the HARQ interlaces. For example, the ordering of the retransmissions in the allocated sub-frames is "ABCD" as seen by A(sub-frame 442), B{sub-frame 443), C(sub-frame 444), D(sub-frame 452), A(sub-frarae 453), B(sub-friaries 454), C(sub-frame 462), D(sub-frame 453), A(sub-5 frame 4 64). The ordering of the ACKs in the allocated sub-frames is A(sub-fraine 447A), B(sub-frame 447B), C(sub-frame 448), DCsub-frame 457A), ACSub-frarae 457B), B(sub-frame 458). As can be seen in Figure 4B, the DL ACK in 447A and 447B for interlaces A and B, respectively, share a. single sub-frame and 10 in 457A and 457B fox interlaces D and A, respectively, share a single sub-fauna. Figure 4C illustrates an example which has a similar 8 sub-frame per frame 5ms radio frame, four sub-frame/four sub-frame per frame partition for UL transmissions and DL ACKs,15 four sub-frame ACK delay, 4 sub-frame Retransmit delay, and TDD DL/UL ratio of 2:3 as illustrated in Figure 4B. In Figure 4C the s\ib-frame location within a radio frame for ACK and retransmission of a HARQ interlace change is fixed- For example, the ordering of the retransmissions in the allocated 20 sub-frames is "ABCDBCABC" as shown by A(sub-frame 472), B(sub-frame 473), C(sub-frame 474), D(sub-frame 482), B(sub-frame 483), C(sub-frame 484), A(sub-frame 492), B(sub-frame 493), B(sub-frame 494). The ordering of the ACKs in the allocated sub-frames is A(sub-frame 477A), B(svib-frame 477B) , C(sub-frame 25 478) D{5ub-fraine 487A), B(sub-fran»e 487B> , C(sub-frame 488>, A{sub-frame 497A), B(sub-frame 497B), B(sub-frame 498). As can be seen in Figure 4C, the DL ACK in 477A and 477B for interlaces A and B, respectively, share a single sub-frame and in 487A and 487B for interlaces D and B, respectively, share a single sub-frame and in 497A and 497B for interlaces A and B, respectively, share a single sub-frame. Referring to Figure 24, a method will now be described for determining the timing for receiving an ACK/NAK at a base station. A first step 24-1 of the method involves, in a system having a known HARQ acknowledgement (ACK) delay, retransmit delay and unrobed of HARQ interlaces, which are each defined in configuration signaling sent to a mobile station 5 and which are a function of at least one of a time division depleting downlink/uplink (TDD DL/ÜL) ratio and a frequency division depleting downlink/uplink (FDD DL/ÜL) ratio, at the base station, determining the timing for receiving an ACK/NAK from a mobile station based on configuration signaling in 10 response to a previously sent transgression of an encoder packet by the base station. In some embodiments, a further step of the method involves sending the configuration signaling. Referring to Figure 25, a method will now be 15 described for determining the timing for receiving one of a transmission and a retransmission of a sub-packet of an encoder packet at a mobile station. A first step 25-1 of the method involves, in a system having a known HARQ acknowledgement (ACK) delay, retransmit delay and number of HARQ interlaces, which 20 are each defined in configuration signaling sent to a mobile station and which are a function of at least one of a time division depleting downlink/uplink (TDD DL/UL) ratio and a frequency division depleting downlink/uplink (FDD DL/uL) ratio, at the mobile station, determining the timing for receiving one 25 of a transmission and a retransmission of a sub-packet of an encoder packet at a mobile station based on the configuration signaling in response to a previously sent NAK by the mobile station, In some embodiments, a further step of the method 30 involves receiving the configuration signaling. Packet transmissions can be persistent assignments, or non-persistent assignments signaled within specific resource partitions. A persistent resource assignment is an assignment of a predefined, usually reoccurring, resource to a user, such that assignment to that user does not require further signaling for each reoccurrence. Persistent assignments are indicated to other users by a resource 5 availability bitmap (RAB), Examples of implementing an RAE can be found in PCT patent application PCT/2008/001980 filed November 5, 2008, which is comivonly assigned to the assignee of the present application and which is incorporated herein by reference in its entirety. Group assignment of resources using a bitmap is used for non-persistent packet assignments, Each group is assigned a separate resource partition. In some embodiraents division and identification of available resources is indicated by a ciulticast control segment 15 (MCCS). In some embodiments, partition of zones is signalled by combination index (Cl) which signals the resource partitions Kithin the persistent and non-persistent zones. Examples of a RAB can be found in coiraconly assigned PCT/2008/001980. In some embodiments, a look-up table is created with possible resource partitions, for a given total number of resources. For example, possible partitioning of 12 resources can be given by (1,2,4,6). Each entry of the look-up table is specified by the C1 index, The C1 can be transmitted. in bit-form, proper encoded, at the beginning of frame, if a persistent sub-zone is specified, the RAB roay be sent. In some embodiments, the C1 is concatenated and encoded with the RAB. The RAB is a bitmap that indicates which resources are available, and which are 30 occupied with a persistent HARQ transmission. The RAB contains one bit for every resource (or resource block}, and the value of the bit indicates whether the resource is in use or civilizable. Persistent resources that are unused due to packet arrival jitter, silence state, or early termination of HARQ 5 transmissions are shown as available. In some embodiments, for reliability, a CRC is appended to the concatenated C1 and RAB. The resource partitions indicated by the C divide the set of resources remaining after resources indicated as occupied by the RAB are 10 removed from the resource list. In some embodiments, the size of the persistent zone is transmitted in a secondary broadcast channel. Referring to Figure 5, an example of a resource availability bitmap will now be described- Figure 5 15 illustrates at least part of a frame 900, having a combination index 910, an RAB 915, a persistent zone 920 that has at least some resources that are persistently assigned, and a non-persistent zone 930 that has no persistently assigned resources. The combination index 910 and the RAB 915 ray together be referred to as a multicast control segment (MCCS)-In the persistent zone there are three partitions 921,924,92"?. Two of the partitions 921,924 are group assigranents and have signaling bitmaps 922,925, respectively. The third assignment 927 is an Uplink Control segment <ÜLCS) for defining unclasp assignments. In some embodiments, the CTS may be implemented in a ranger similar to that described above with reference to Figure 2. In the Non-persistent Zone 930, one of the partitions 940 is a Group control and traffic segment (GCT5) which is used 30 for defining group assignments. Two other partitions 930 and 950 are Nicest control and traffic segments (UCTS) used for defining nicest assignment. In some embodiments, the UCTS may irapleraented in a manner similar to that described above for the DL UCTS with reference to Figure 2. With reference to group assignment 924, group assignment 924 has a signaling bitmap 925 that includes an 5 assignment bitmap 940, a pairing or sets combination index bitmap 941 and a resource permutation index bitmap 942. The assignment bitmap S40 has 6 bits* one bit for possible assignment to each sneer. The pairing or sets combination index bitmap 941 has 4 bits. The resource permutation bitmap 942 has ^ 10 2 bits. Group assignment 921 has a signaling bitmap as well. In group assignment 924 also indicated is a persistently assigned resource 926 (gray shaded portion of group assignment 924) that is in use and as such is not available for assignment to other users. Similar persistent 15 assignments are shown in group assignments 921 and 927. In some embodiments, superposition can be used to transmit multiple packets on the same resource by making use of different users' geometries, and an altered packet structure for to enable interference cancellation of some packets while 20 maintaining security. In some embodiments, superposition of multiple assignments can be achieved by assigning them to the same resources, or set of resources- In some embodiments, this process can -be used to superposition persistent and non-persistent assignment Multiplexing of persistent assignments can be achieved by indicating a "busy" resource, as available in the RAB. By indicating a persistent used resource as available in the RAB, other indicated assignments will use the resource as 30 well {groups or otherwise). Hence the persistent transmission and other transmissions will be sent simultaneously on the same resource. If all persistent assignments are to be indicated as available, the RAB does not need to be sent. In some embodiments, superposition can also be used to multiplex users on the downlink by allowing a persistent 5 user and other signaled user{s) to be allocated to the same resource. This is useful for faulty-user MIMO applications. Superposition of the persistent assignment and signaled assignment can be achieved this way. A decision to indicate a persistent assignraent 10 resource that is in use as "busy" or "available" in the RAB can be made at the base station dynamically for each assignment, in each time frame. The decision may be based on at least one of: geometries of mobiles for which the different packets are 15 intended and reliability of the different packets, users that have high geometry are users that have good long-term channel conditions for communicating with their serving base station. Therefore, it is desirable in some situations to provide bitmaps for users with generally good channel conditions- A mobile station is configured to check for presence of super positioned persistent assignment by determining that its transmission occurs in the persistent sub-zone- In some embodiments the mobile station is configured to check for presence of super positioned persistent assignment by detecting an indication of a "number of layers" field, which can be appended to the C1 (within MCCS field). In some embodiments, the field may correspond to the number of layers, either superposition or MIMO, for each partition. In some embodiments, the mobile station is configured to check for presence of super positioned persistent assignment based on received power threshold detection. In some embodiments, the mobile station is configured to always check for presence of super positioned persistent assignment. In some embodiments the packet intended for the lower geometry mobile station (e.g. persistent assignment) can be encoded in a manner that allows it to be decoded. In some embodiments, the decoding is verified with the use of a CRC, 5 which enables the transmission to be used for interference cancellation (IC). However, users that decode the transmission will not be able to have access to the usable data as it will remain scrambled by the intended user's identification (ID) sequence- In some systems, a persistent assignment can be used. Persistent assignment is defined as an assignment on a predefined resource for one or more HARQ transmissions. It is possible to assign other user(s) to the same resource. Nicest or group signaling are two examples of such signaling method to assign these resources. The base station may utilize the some resource for transmitting one or more persistent assignments, and one or more signaled assignments in order to improve capacity. The persistent packet transmission is altered in a manner to allow the mobile station receiving a non-persistent transmission to receive and decode it for the purpose of interference cancellation, without the ability to describable it. A mobile station receiving a persistent transmission decodes the altered packet in a regular fashion, adding extra steps to undo the alteration to allow it to be decoded for the purpose of interference cancellation of the packet. In general, when two or more packets are super positioned on the DL and are intended for different users, the packet transmission with a higher reliability (packet A) is 30 altered in a manner to allow the mobile station intended to receive a different transmission (with lower reliability, (packet B)), to receive the higher reliability transmission (packet A) and decode it for the purpose of interference cancellation, without the amity to descramble it. A mobile station intended. to receive a packet that has been altered to allow a different sugar(s) to decode it for the purpose of interference cancellation, decodes the altered packet in a 5 regular fashion, but includes extra steps to undo the alteration the packet. A mobile station intended to receive the altered packet (packet A) transmission that has been superpositioned with another packet decodes the altered packet. As the packet that is sent at higher reliability ixia 10 be readily decoded at a different mobile station after only one transmission, the mobile can make use of the decoded higher reliability packet for interference cancellation of its own transmission in each frame. One transmission can be sent with "higher reliability" by any one of, but not librated to: using a 15 higher power level; using a more robust coding scheme; and using a higher processing gain (i-e- spreading). This process may be used for both Chase combining case and incremental redundancy (IR) HARQ transmission case. Process for superpositioned packet to be used in interference 20 cancellation The packet intended for the lower geometry mobile (e-g. persistent assignment) can be encoded in a manner that allows it to be decoded by others users, and verify decoding with a CRC, enable use of the transmission for efficient 25 interference cancellation (IC). However, these user with not be able to have access to the usable data as then it will remain scrambled by the intended users Identification sequence. This process involves using two cyclic redundancy checks (CRC's); a first CRC is applied before scantling by the 30 intended user identification sequence and a second CRC is applied after. other mobile stations will be able to use the second CRC for confirming correct decoding of the transmission. while the first CRC confirms the intended user of the packet after correct descrambling. In order to enable superposition and detection involving interference cancellation of one or more layers of 5 packets for applications such as transmission of two (or N, where N equals the numbers of users) different packets, to two (or )H) different users. The packet that is sent at higher reliability can be further appended with a CRC and scrambled with an identifying sequence, in addition to nominal encoding 10 and caroling procedures. Referring to Figure 6A, an sextuple of how a packet 610 with an appended CRC 'A' 612 is scrambled and encoded in a conventional manner will now be described. The packet 610 includes N data bits. The CRC *A' 612 is appended to the end of packet 610. The combined data and CRC are scrambled using an identification sequence. In some implementations the Identification sequence may be one of, but not limited to, a sector ID and a user 1D or a MAC ID, to create a scrambled packet 620- The scrambled packet is then encoded, to created an encode packet 630. In some implementations the encoding may be one of, but not limited to, turbo encoding, convolution encoding, LDPC encoding. Referring to Figure 6B, an example of how a packet 640 with an appended CRC 'A' 642 is scrambled and encoded and 25 then the encoded packet €60 appended with another CRC 'B' 662 and scrambled again according to an embodiment of the Invention will now be described. Such a method can be used in interference cancellation for superpositioned packets-The first several steps are similar to the steps 30 described above with regard to Figure 6A and result in an encoded, scrambled packet 660. A CRC ^B' 662 is appended to the end of the encoded, scrambled packet 660. The encoded packet 660 and CRC *B' 662 are scrambled using an additional Identification sequence known to multiple users to create a scrambled packet 670, thus allowing any of the multiple users to descramble the scrambled packet. In some implementations the Identification sequence may be a sector ID. The scrambled 5 packet 670 i3 then encoded, to create an encoded packet 680. In some implementations the encoding may be one of, but not librated to, turbo encoding, convolution encoding, LDPC encoding. The second scrambling step is optional and may not be 10 used in al implementations. In some cases for either process, the scrambling with Identification sequence can be performed on the data only, CRC only, or both Data+CRC. Other scrambling, interleaving, modulation block may 15 be added to this chain. Only essential steps significant to this description are incluced. Process for detection and reception of packets at two mobiles Referring to Figure 7, an example of how superpositioned packets may be transmitted and decoded using 20 interference cancellation according to the double scrambling and double encoding described above, will now be described. Mobile Station A 720, at a lower relative geometry, is intended to receive Packet A 712 that has been altered according to double scramble/double encoding described above. 25 The resource for transmitting the packet may be persistently assigned. Mobile Station B 730, at a higher relative geometry, is intended to receive Packet B 714 that has been encoded according to single scramble/single encoding described above. 30 Both packets are sent on they same resource. If the transmission for Packet A 712 is persistently assigned, the resource is indicated as "'available" on the RAB. It is possible that multiple packets belonging to one on more users are sent on resources that overlap for seine transmissions. Process At Mobile A An attempt to decode and descramble the "outer layer" 5 of encoding and scrambling, if the outer layer of scrambling is used, is made for Packet A 712, using CRC ''B' for verification of correct decoding. If Packet A 712 ±s decoded successfully, the packet is descrambled with an Identification sequence using CRC *A' for verification of correct decoding/descraitibling. if 10 not decoded successfully/ a re-transmission process is followed as specified by HARQ/ if desired. In some embodiments, this may include RAS-HARQ retransmission using the control Information signaling techniques described above. For example, in HARQ the unsuccessful transmission 15 may be retained at the mobile to be combined in some way (incremental redundancy or chase confining) with additional retransmissions. Process At Mobile B An attempt to decode and describe (if used) packet 20 A, is made using CRC 'B' for verification of correct decoding. If decoded successfully/ interference cancellation can be used to essentially remove Packet A 712 from the combined transmission of Packet A 712 and Packet B 714, which is intended for Mobile B 730, since the two packets are 25 transrnitted in the same resource. If Packet B 714 is not decoded successfully, HARQ schemes can be used to try to recover the packet, If other packets are superpositioned, either partially or completely with Packet B, an attempt can be made 30 to detect and cancel these packet as well using similar processes of successive interference cancellation. From the resulting signal, an athirst can be made to decode Packet B- If desired, a HARQ re-transmission process can be used in recovering and detecting the packet. For example, in HARQ the unsuccessful transmission may be retained at the mobile to be combined in sonnies way 5 (incremental redundancy or chase combining) with additional retransmissions. Successfully decoded packets intended for other users can be used for additional channel estimation reliability. Fewer level may need to be detected blindly, if not known. Benefits of the above process include: 1) enabling superposition, and thereby reducing resources used for transmission (capacity enhancement); 2) making use of targeting different geometries so that a transmissions are sent with different reliabilities. In some embodiments, a transmission arrives at a different mobile, and can be reliably received to enable interference cancellation without re-transmissions. In some embodiments, transmission intended far mobile with lower geometry is not significantly affected by presence of superpositioned packet; 3) allowing a mobile station to decode and use a packet intended for a different mobile for the purpose of interference cancellation, without allowing the mobile to de-scramble the actual usable data; 4) allowing persistent resources to be indicated as "available", which allows the RAB to be shortened or orated as default without RAB for resources is "''available"; 5) the additional cost is only an additional CRC appended to transmissions. In some embodiments the process is especially useful 30 for VoIP applications as packet sizes/coding rates/modulation scenes are librated to a finite number of hypothesis. In some applications, the VoIP packet to used for interference cancellation may be a fixed parameters (or very limited set). For Example, one modulation and coding scheme for each packet size, with fixed resource allocation size. DL Control Channel Structure In some embodiments, sub zones can be created within a frame structure to enable DL channel control. A frame is a physical construct for transmission that once it is set is net changed/ while a sub zone is a portion a frame that is configurable as a scheduling construct, whose size and shape 10 may change within the frame for a given situation, For example, in an OFDM application, sub zones may corsets of multiples of 2 OFDM synods over a block of sub carriers- In some embodiments, the block of sub-carriers is the entire set of the sub-carriers of an available band. In some embodiments, a basic charnel unit (BCU) allocation block (BAB) may consist of one or rare BCUs. A BCu is a two dimensional time-frequency transmission resource, i.e-a given number of symbols over a given number of sub-carriers. The sub-carriers may be physical sub-carries or logical sub- carriers that are permuted based on a particular rapping of physical sub-carries to logical sub-carries. In some embodiments, within a sub zone, a BAB has a same n\jabber of tine-frequency resource blocks per OFDM symbol. In some embodiments, this may be true when averaged over one or more frames- While OFDM symbols are referred to specifically, it is to be understood that OFDM is considered for illustrative purposes, and other transmission formats are contemplated. In some embodiments, different sub zones may have different BAB configurations. For example, a first sub zone has 30 4 OFDM symbols in which each BAB has 2 BCUs. In another example, a second sub zone has 4 OFDM symbols, in which some BABs have 4 BCüs and other BABs have 8 BCUs. In yet another example, a third sub zone has 6 OFDM symbols, in which each BAB has 12 BCus. In some embodiments, an extended frame can be supported by defining a separate zone. The BCus in the 5 separate zone of the extended frame use the same canalization as in the non-extended frame zone. No additional complexity is required. In some embodiments, in the separate zone of the extended frame, the control channel, be it an MCCS or a nicest 10 control channel, occurs every k frames. Each assignment in the separate zone of the extended frame is for k frames. The nicest control information is contained within an associated partition in the first sub-frame. In this design, transmissions using extended sub-frames can co-exist 15 with transmissions using non-extended sub-frames. This way only the mobiles that use the extended zone are affected by the increased latency. A separate zone in the extended frame can be defined for ÜL transmissions as well for DL transmissions. In some embodiments, an access grant message contains a user ID of a mobile station that initiated a request for access. An access grant message is contained in a UL control segment and it is scrambled by the sequence that the mobile station used in the uL random access channel. In some embodiments, the UL control segment contains the following fields: an MCCS, a nicest assignment message, a group assignment message and a UL access grant message. The MCCS contains a combination index and/or permutation index and a RAB if persistent resources have been allocated. Exorable pertaining to implementation of the combination index, permutation index and RAB can be found in commonly assigned PCT/2008/001980- The nicest assignment message may include multiple nicest assignment messages, one for each assignment. The group assignment message may include multiple group assignment messages, one for each assignment. Persistent resources are allocated using a persistent 5 assignment message. There are separate persistent assignment messages for both DL and ÜL assignments, In some embodiments, each message contains a resource ID (BCU) and a nearer of resources assigned. In some embodiments each message contains a bitmap indicating the assigned resources In the bitmap 10 approach, the length of the bitmap is the length of the persistent zone. In some embodiments, the length of the persistent zone is signaled in a super-frame control. In some implementations, a UL persistent assignment message is contained in the UL control segment. In some 15 implementations, the UL persistent assignment message is contained in a separate partition. In some implementations, DL/UL persistent assignment messages are scrambled by the user ID of the intended user. In a multi-user MIMO (Mu-MIMO) case, in which 20 multiple users are assigned to a same partition of a transmission resource, separate nicest messages are provided for each user assigned to the same partition. In some embodiments, the unicast control segment contains a MU-MIMO header, which is a raulticast message that is targeted to the lowest geometry user in the assignment. The Mü-MIMO header contains Information identifying a message type, which indicates a number of layers that are multiplexed on to the same resource and a pre-coding matrix index (PMI) that is used for the transmission in the case of codebook based pre- coding feedback. The PMI is a matrix with a number of columns equal to the nearer of layers that are multiplexed on a resource. Each column consists of a pre-coding vector for the corresponding layer. In some embodiments, the Mu-MIMO header is CRC protected. This is then foliowed by individual unicast 5 messages for each assignment. The individual unicast messages contain the MCS of the assignraent. In some impleirentations each unicast message is scrambled by the user ID of the intended user. In some implementations the unicast messages are CRC protected. In some embodiments, the DL ACK channel is used to acknowledge UL data transmission. A flexed unlimber of diversity resources are allocated to a group of control channels that includes, but is not limited to: DL ACK; UL power control channel; and the MCCS. In some implementations, the number of resources for the DL ACK channels and the location of the resources are signaled in a super-frame control. In some implementations, each DL ACK channel consists of N tones that are spread over the entire band. In some implementations, each DL ACK channel is power controlled to the intended user. In some implementations, for the DL power control channel, ones channel is assigned to each user for the purpose of power control. Multi-carrier Configuration for OFDM System According to another aspect of the invention there 25 are provided methods for adjacent multi-carrier configuration of OFDM System to ensure sub-carriers alignment between adjacent carriers. In a current WiMAX/802,16e schemes, the free agency raster of 250kHz is not divisible by the WiMAX/802.16e sub-30 carrier spacing of 10.94kHz. In a situation where the spacing of center frequencies of adjacent carriers are an integer multiple of the raster size of 250kHz, the OFDM sub-carriers between two adjacent carriers are not aligned. Referring to Figure 8, an example is illustrated in which a first carrier is shown having a first set of sub-carriers and a second carrier is shown having a second set of sub-carriers. The spacing of 5 the center frequencies of the first carrier and the second carrier is N x 2501cHz, which Is not divisible by 10.94kHz. This situation of non-aligned sub-carriers will cause inter carrier interference. A proposed solution to this problem is changing the 10 sub-carrier spacing to 12.5kHz which is divisible by raster size of 250kHz. However, this solution introduces a new sub¬carrier spacing that is not backward compatible with existing wiMAX schemes. To support backward compatibility, three sets of OFDM 15 sub-carrier spacing have been adopted in IEEE 802.16ni-08/003rl. These spacings include 7.81kHz, g.TkHz and 10.49kHz. However, details regarding adjacent carrier configuration such as carrier spacing, sub-carrier alignment and guard tones have not been described. For the cases of sub-carrier spacing of 7.81kHz and 9.77kH2, the corresponding system bandwidth is divisible by the proposed sub-carrier spicing. Therefore, in a multicarrier deployment, the center frectuencies of adjacent carriers are spaced by integer unlimber of sub-carriers. In a case in which a wireless device© that is compatible with IEEE802.16m is used for cominunication, there is a zone of a resource allocated for IEEE802.16m transmissions. No guard tones are required on sub-frames within the IEEE802.16m zone between adjacent carriers beyond the carrier 30 bandwidth. However, to support backward coir-atibility, sub-frames within a zone allocated for legacy supported carriers contain guard tones between adjacent carriers. In some implementations, guard tones between adjacent carriers are consistent with those guard tone arrangements defined in legacy System permutation formats. With reference to Figure 9, an example of two adjacent carriers each having both legacy and ÏEEE802.16m DL and UL sub-frame components will now be discussed. A first carrier 510, having multiple sub-carriers that are not individually shown, but rather which are shown as a block of frequencies in the vertical direction is illustrated over two successive 5ms radio frames 530,550. A DL portion of each radio frame includes four sub-frames, two of which are legacy sub-frames 533 and two of which are IEEE802.l6m sub-frames 534. A UL portion of each radio frame includes four sub-frames, one of which is a legacy sub-frames 543 and three of which are IEEE802.16m sub-frames 544. A second carrier 520, having multiple sub-carriers in a block of frequencies in the vertical direction is illustrated over two successive Sms radio frames. A DL portion of each 20 radio frame includes four sub-frames, one of which is a legacy sub-frames 537 and three of which are IEEE802.16m s\ib-frames 538. A UL portion of each radio frame includes four sub-frames, two of which are legacy sub-frames 5473 and two of which are IEEE802.16m sub-frames 548. In the first carrier 510, some sub-carriers of the legacy DL sub-frames 533 are allocated as guard tones 535 between the sub-carriers of the first carrier 510 and the sub-carriers of the second carrier 520. In the second carrier 520, some sub-carriers of the legacy DL sub-frames 537 are allocated as guard tones 536 between the sub-carriers of the second carrier 520 and the sub-carriers of the first carrier 510. However, no guard tones are needed between the sub-carriers of the first carrier 510 and the sub-carriers of the second carrier D20, or vice versa, if the sub-frames are IEEE802.16ra sub-frames- In the first carrier 510, some sub-carriers of the legacy UL sub-frames 543 are allocated as guard tones 545 5 between the sub-carriers of the first carrier 510 and the sub-carriers of the second carrier 520- In the second carrier 520, some sub-carriers of the legacy ÜL sub-frames 547 are allocated as guard tones 546 between the sub-carriers of the second carrier 520 and the sub-carriers of the first carrier 510. 10 However, no guard tones are needed between the sub-carriers of the first carrier 510 and the sub-carriers of the second carrier 520, or vice versa, if the sub-frames are IEEE802.16in sub-frames- Figure 9 is a particular example for a given size 15 radio frame, number of DL and uL sub-frames and arrangement of legacy and IEEE802.16m supported carriers. These parameters are implementation specific and therefore tabs particular example of Figure 9 is not intended to limit the invention-Furthermore, while IEEE802.16in supported carriers are 20 specifically referred above, more generally, the invention can be applied to other supported carriers that are non-legacy supported carriers. For the case of sub-carrier spacing of l0.94kKz, system bar widths of 5/10/20MHZ are not divestible by the sob-carrier spacing. However, N x 1.75MH2, e,g. 5.25MHz, 10.5MHz, 21MHz are divisible by the sub-carrier spacing. In a situation in which two adjacent carriers are legacy support carriers, the center frequencies of the adjacent carriers are spaced apart by the carrier bandwidths in order to ensure backward compatibility. Guard tones are used between the adjacent carriers. If a non-legacy support carrier is adjacent to a legacy support carrier, the center frequency of the non-legacy carrier can be offset such that the center frequencies of the two adjacent carriers can be spaced by 5.25/10.5/21MHz respectively for carrier bandwidth of 5/10/20MH2 respectively. Therefore, the center frequency spacing of adjacent carriers 5 can be set to multiples of 5.25MHz to avoid the sub-carrier misalignment issue. For example, two adjacent 5MHz carriers are spaced by 5.25MHz. Tv/o adjacent IOMHz carriers are spacing by 10.5MHz. An illustration for carrier bandwidth of 5MHz is shown in Figtare 10. For the non-legacy carrier, as shown in 10 Figure 10 (next slide), uneven number of guard sub-carriers are used on both sides of a carrier. On a sub-frame within the non-legacy carrier supported zone, no guard tones are required between adjacent carriers beyond the carrier bandwidth. On a sub-frame within 15 the legacy carrier supported zone, guard tones are still used between adjacent carriers on sub-frames within the legacy zone. Figure 11 illustrates an example of two adjacent carriers one having legacy support carriers and one having non-legacy supported carrier in two consecutive 5ms radio 20 frames 1130,1150. A first carrier 1110 that includes legacy support, having multiple sub-carriers that are not individually shown, but rather which are shown as a block of frequencies in the vertical direction is illustrated over two successive 5ms radio frames. A DL portion of each radio frame includes four sub-frames, two of which are legacy sub-frames 1131 and two of which are non-legacy sub-frames 1133. A ÜL portion of each radio frame includes four sub-frames, one of which is a legacy sub-frames 1141 and three of which are non-legacy sub-frames 1143. A second carrier 520 that does not include legacy support, having multiple sub-carriers in a block of frequencies in the vertical direction is illustrated over two successive 3ms radio frames. A Dt portion of each radio frame includes four sub-frames, all of which are non-legacy sub-frames 1136. A UL portion of each radio frame includes four sub-frames, all of which are non-legacy sub-frames 114 6. In the first carrier 1110, some sub-carriers of the legacy DL sub-frames 1131 are allocated as guard tones 1135 between the sub-carriers of the first carrier 1110 and the sub-carriers of the second carrier 1120. In the second carrier 1120, no sub-carriers are allocated as guard tones between the 10 sub-carriers of the second carrier 1120 and the sub-carriers of the first carrier 1110. In the first carrier 1110, some sub-carriers of the legacy UL sub-frames 1141 are allocated as guard tones 1145 between the sub-carriers of the first carrier 1110 and the sub-15 carriers of the second carrier 1120. In the second carrier 1120, no sub-carriers are allocated as guard tones between the sub-carriers of the second carrier 1120 and the Sub-carriers of the first carrier 1110. In a specific embodiment, for the case of 2 adjacent 20 5MMz carriers, although the adjacent carriers are spaced by 5.25MHz, there is no wasted bandwidth in between the carriers since the WiMAX OFDM numerology uses over-sampling rate- The effective bandwidth for a 512-FFT is 5.6MHZ. In some implementations, by adjusting the guard sub-carriers on both 25 sides, the gaps between two adjacent carriers can be removed. Furthermore, by adjusting the guard sub-carriers on both sides out-of band spectrum mask requirements may also be met- This is illustrated in Figure 12a. As shown in Figure 12a, an uneven number of guard 30 sub-carriers are used on both sides of a carrier. A number of guard sub-carriers between two adjacent carriers is 16 on each carrier. A number of guard sub-carriers at the edge of the spectrum is adjustable based on the spectrum mask requirements. There are two scenarios as illustrated in Figures 12a and 12b and Figures 13a, 13b and 13c. Scenario 1 - An even distance between the center carrier frequencies of each carrier and the spectrum boundary As shown in Figure I2d and Figure 12b, the center frequencies are 2.625MH2 (or 10.5 rosters) from the 5MHz spectrum boundary. The drawback of this scenario is the center frequency locations are not aligned with the raster boundaries. Scenario 2 - An uneven distance between the center carrier 10 frequencies of each carrier and the spectrum boundary In scenario 2 center frequency locations are aligned with raster boundaries. As shown in Figure 13a and 13b, the center frequency of carrier 1 is spaced 11 rosters flora the 5MH2 spectrum boundary. The center frequency of carrier 2 is spaced by 10 rosters from the 5MHz spectrum boundary, This results in an uneven nursery of guard sub-carriers between two adjacent carriers. As shown in Figure ISa, the guard sub-carriers on carrier 1 on the side that is knelt to carrier 2, is 5. The guard sub-carriers on carrier 2 on the side that is 20 next to carrier 1, is 28. The number of guard sub-carriers at the edge of the spectrum is adjustable based on the spectrum mask requirements. Figure 13c further shows a general case of more than two adjacent carriers. The spacing of the center frequency 25 from the spectrum boundary is adjusted to ensure the center frequency is aligned with the raster boundaries. In addition, the spacing between center frequencies of adjacent carriers is maintained at 21 rosters. In a specific embodiraent that consists of a legacy 30 WiMAX carrier, the carrier frequency of the legacy carrier has to be centered in the SMHz band as shown Figure 14. In this case the adjacent non-legacy carrier has to be further offset in order to maintain the overall 5.25MH2 spacing between the center frequencies. As shown in Figure 14^ for the legacy carrier, a same number of guard sub-carriers are used on both sides of the carrier. For the nonliterary carrier, an uneven 5 number of guard sub-carriers are used on both sides- of a carrier. A number of guard sub-carriers on the side that is adjacent to the legacy carrier, is 3 sub-carriers. A number of guard sub-carriers at the edge of the spectrum is adjustable based on the spectrum mask requirements. For other carriers in 10 the spectrum which are not adjacent to a legacy carrier, the approaches described with reference to Figures 12a, 12b, 13a, 13b and 13c, may be used. In soirée erabodirents a method is provided to offset the spacing of the center frequencies of adjacent OFDM carriers 15 to ensure the carrier spacing is divisible by the sub-carrier spacing. In some embodiments a method is provided to offset the spacing of the center frequencies of adjacent OFDM carriers to have a spacing that is not equal to the bandwidth of each 20 carrier In some embodiments a method is provided to allocate uneven number of guard sub-carriers on both sides of the carrier In some embodiments a method is provided to mix the 25 regular carrier that has same number of guard sub-carriers on both side of the carrier and has center frequency located at the middle of the bandwidth, with a carrier that has uneven number of guard sub-carriers on both side of the carrier and has center frequency that is offset of the middle of the 30 bandwidth. Description of example components of a communication system A high level overview of the mobile terminals 16 and base stations 14 upon which aspects of the present invention are impleraented is provided prior to delving into the 5 structural and functional details of the preferred embodiments. with reference to Figure 15, a base station 14 is illustrated. The base station 14 generally includes a control system 20, a base band processor 22, transmit circuitry 24, receive circuitry 26, multiple antennas 28, and a network interface 30. The 10 receive circuitry 26 receives radio frequency signals bearing information room one or more remote transmitters provided by mobile terminals 16 (illustrated in Figure 1). A low noise amplifier and a filter (not shown) may co-cerate to amplify and remove broadband interference from the signal for 15 processing. Dovfnconversion and digitization circuitry (not shown) will then down convert the filtered, received signal to an intermediate or base band frequency signal, which is then digitized into one or more digital streams. The base band processor 22 processes the digitized 20 received signal to extract the Information or data bits conveyed in the received signal. This processing typically comprises demodulation, decoding, and error correction operations. As such, the base band processor 22 is generally implemented in on© or more digital signal processors (DSPs) or 25 application-specific integrated circuits (ASiCs). The received Information is then sent across a wireless network via the network interface 30 or transmitted to another mobile terminal 16 serviced by the base station 14. On the transmit side, the base band processor 22 30 receives digitized data, which may represent voice, data, or control Information, from the network interface 30 under the control of control system 20, and encodes the data for transmission. The encoded data is output to the transmit circuitry 24, where it is modulated by a carrier signal having a desired transmit frequency or frequencies. A power amplifier (not shown) will amplify the modulated carrier signal to a level appropriate for transmission, and deliver the inoculated carrier signal to the antennas 28 through a matching network. (not shown). Various modulation and processing techniques available to those skilled in the art are used for signal transmission between the base station and the mobile terminal. With reference to Figure 16, a mobile terminal configured according to one embodiment of the present invention is illustrated. Similarly to the base station 14, the mobile terminal 16 will include a control sister 32, a base band processor 34, transmit circuitry 36, receive circuitry 38, multiple antennas 40, and user interface circuitry 42. The receive circuitry 38 receives radio frequency signals bearing Information from one or more base stations 14. A low noise amplifier and a filter (not shown) may co-operate to amplify and remove broadband interference from the signal for processing. Downconversion and digitization circuitry (not 20 shown) will then downconvert the filtered, received signal to an intermediate or baseband frequency signal, which is then digitized into one or more digital streams. The base band processor 34 processes the digitized received signal to extract the Information or data bits 25 conveyed in the received signal. This processing typically comprises demodulation, decoding, and error correction operations. The base band processor 34 is generally impleraented in one or more digital signal processors (DSPs) and application specific integrated circuits (ASICs). For transmission, the base band processor 34 receives digitized data, which may represent voice, data, or control intonation, from the control system 32, which it encodes for transmission. The encoded data is output to the transmit circuitry 36, where it is used by a modulator to modulate a carrier signal that is at a desired transmit frequency or frequencies. A power amplifier (not shown) will amplify the modulated carrier signal to a level appropriate for 5 transmission, and deliver the modulated carrier signal to the antennas 40 through a matching network (not shown). Various adulation and processing techniques available to those skilled in the art are used for signal transmission between the mobile terminal and the base station. In OFDM modulation, the transmission band is divided into multiple, orthogonal carrier waves- Each carrier wave is modulated according to the digital data to be transmitted. Because OFDM divides the transmission band into multiple carriers, the bandwidth per carrier decreases and the modulation time per carrier increases. Since the multiple carriers are transmitted in parallel, the transmission rate for the digital data, or symbols, on any given carrier is lower than when a single carrier is used. OFDM modulation utilizes the performance of an 20 Inverse Fast Fourier Transform (IFFT) on the Information to be transmitted. For demodulation, the performance of a Fast Fourier Transform (FFT) on the received signal recovers the transmitted Information. In practice, the IFFT and FFT are provided by digital signal processing carrying out an Inverse 25 Discrete Fourier Transform (IDFT) and Discrete Fourier Transform -carriers over a given time and frequency plot in an OFDM environment are found in PCT 5 Patent Application No. PCT/CA2005/000387 filed March 15, 2005 assigned to the same assignee of the present application. Continuing with Figure 18, the processing logic compares the received pilot symbols with the pilot symbols that are expected in certain sub-carriers at certain times to determine a channel response for the sub-carriers in which pilot symbols were transmitted. The results are interpolated to estimate a channel response for most, if not all, of the remaining sub-carriers for which pilot symbols were not provided- The actual and interpolated channel responses are used to estimate an overall channel response, which includes the channel responses for most, if not all, of the sub-carriers in the OFDM channel. The frequency domain symbols and channel reconstruction Information, which are derived frond the channel responses for each receive path are provided to an STC decoder 20 100, which provides STC decoding on both received paths to recover the transmitted symbols. The channel reconstruction Information provides equalization Information to the STC decoder 100 sufficient to remove the effects of the transinission channel when processing the respective frequency domain symbols The recovered symbols are placed back in order using synod de-interleave logic 102, which corresponds to the symbol interleave logic 58 of the transporter. The de-interleaved symbols are then demodulated or de-mapped to a 30 corresponding bit stream using de-mapping logic 104. The bits are then deinteleaved using bit de-interleave logic 106, which corresponds to the bit interleave logic 54 of the transmitter architecture. The de-interleaved bits are then processed by rate de-matching logic 108 and presented to channel decoder logic HO to recover the initially scriptable data and the CRC checksum. Accordingly, CRC logic 112 removes the CRC checksum, checks the scrambled data in traditional 5 fashion, and provides it to the de-scrambling logic 114 for de-scrambling using the known base station de-scrambling code to recover the originally translated data 116. In parallel to recovering the data 116, a CQI, or at least Information sufficient to create a CQi at the base station 14, is determined and transmitted to the base station 14. As noted above, the CQI may be a function of the carrier-to-interference ratio (CR), as well as the degree to which the channel response varies across the various sub-carriers in the OFDM frequency band. The channel gain for each sub-carrier in the OFDM frequency band being used to transmit Information is compared relative to one another to determine the degree to which the channel gain varies across the OFDM frequency band. Although numerous techniques are available to measure the degree of variation, one technique is to calculate the Standard deviation of the channel gain for each sub-carrier throughout the OFDM frequency band being used to transmit data-Figures 1 and 15 to 18 each provide a specific example of a communication sister or elements of a communication system that could ba used to implement embodiments of the invention. It is to be understood that embodiments of the invention can be implemented with Communications systems having architectures that are different than the specific example, but that operate in a manner consistent with the implementation of the embodiments as described herein. Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. CIAIMS: 1. A method comprising: for a HARQ process, the HARQ process comprising a first transmission of an encoder packet and at least one 5 retransmission, In which a transmission resource for each respective transmission is allocated; transmitting control information from a base station to a mobile station for each respective transmission, the control information comprising: information to uniquely identify the HARQ process; and an Identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the transmission. 2. The method of claim 1 wherein transmitting information to uniquely identify the HARQ process includes transmitting one of; an encoder packet identifier (ID) to uniquely identify the encoder packet; and a resource identifier (ID) of a previous transmission. 3. The method of claim 1 wherein transmitting control information for the first transmission also comprises one or more of: a modulation and coding scheme (MCS) for the encoder packet; a MIMO mode used for transmitting the encoder packet; and one or more other pieces of control information 30 relevant to the HARQ transmission of the encoder packet. 4. The method of claim 1 wherein transmitting control Information further comprises: scrambling the control Information using a user identifier (ID) associated with the mobile station. 5. The method of claim l wherein for allocating a transmission resource for at least one unicast Uplink (UL) transmission, transmitting control Information comprises: transmitting a UL control segment that is a portion of a DL transmission resource, the UL control segment comprising a portion that identifies a location in the UL control segment for transmitting unicast control information for each at least one unicast UL transmission and a portion that defines the control information for use in transmitting the unicast UL transmission. 6. The method of claim 1 wherein for allocating a transmission resource for at least one unicast Downlink. (DL) transmission, transmitting control information comprises: for each at least one unicast DL transmission, transmitting a DL unicast control and traffic segment comprising a portion of the DL unicast control and traffic segment that defines the control information for use in transmitting the unicast DL transmission and a portion of the DL unicast control and traffic segment for transmitting data for the respective unicast DL transmission. 7. A method for acknowledging a DL HARQ transmission comprising: receiving an encoder packet; if the encoder packet is successfully decoded, transmitting an acknowledgement (ACK); if the encoder packet is not successfully decoded, transmitting a negative acknowledgement (NAK); if no retransmission is received within a. predetermined time period of transmitting the NAK, transmitting a NULL indicating that no control information signalling pertaining to the retransmission has been received. 8. A method for acknowledging a DL HARQ transmission comprising: if an acknowledgement (ACK) in response to a previously transmitted encoder packet has been received, not retransmitting an encoder packet; if a negative acknowledgement (NAK) in response to a previously transmitted encoder packet has been received, retransmitting a sub-packet of the encoder packet; if a NULL is received indicating that no control information signalling has been received by a sender of the 15 NULL regarding a previously transmitted encoder packet, retransmitting at least a sub-packer of the encoder packet. 9. The method of claim 8 wherein retransmitting at least a sub-packet of the encoder packet if a NULL is received comprises: if the NULL is received in response to a previously transmitted sub-packet of an encoder packet that is a first sub-packet transmission, retransmitting the first sub-packet transmission, the first sub-packet transmission comprising control information signaling sent in a first sub-packet transmission; if the NULL is received in response to a previously transmitted sub-packet of an encoder packet that is a subsequent sub-packet transmission to a first sub-packet transmission, retransmitting the subsequent sub-packet 30 transmission, the subsequent sub-packet transmission comprising control information signaling that comprises: information to uniquely identify the HARQ process; and an identification of one of a time resource, a frequency resource and a time and frequency resource that is 5 allocated for the subsequent sub-packet transmission- 10. The method of claim 9 wherein retransmitting control information signalling to uniquely identify the HARQ process includes transmitting one of: an encoder packet identifier (ID) to uniquely 10 identify the encoder packet; and a resource identifier (ID) of a previous transmission. 11. The method of claim 9 wherein retransmitting control information signaling sent in the first sub-packet transmission comprises: information to uniquely identify the HARQ process; an identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the transmission; and one or more of; a modulation and coding scheme (MCS) for the encoder packet; a MIMO mode used for transmitting the encoder packet; and one or more other pieces of control information relevant to the HARQ transmission of the encoder packet. 12. A method for rescheduling a UL HARQ transmission comprising: if an encoder packet is not successfully decoded, scheduling an UL transmission of a sub-packet at a predetermined time interval; and transmitting control Information pertaining to the UL 5 transmission according to claim 1. 13. A method of error recovery for a UL HARQ transmission comprising: if a NULL is received in response to a previously transmitted sub-packet of an encoder packet that is a first sub-packet transmission; dynamically scheduling a retransmission of the first sub-packet transmission at any time; retransmitting the first sub-packet transmission, the first sub-packet transmission comprising control information signaling sent in a first sub-packet transmission; if a NULL is received in response to a previously transmitted sub-packet of an encoder packet that is a subsequent sub-packet transmission to a first sub-packet transmission; scheduling a retransmission of the first sub-packet transmission at a predetermined time; retransmitting the subsequent sub-packet transmission, the subsequent sub-packet transmission comprising control signaling Information that comprises: information to uniquely identify the HARQ process; and an identification of one of a time resource, a frequency resource and a time and frequency resource that is allocated for the subsequent sub-packet transmission. 14. A method comprising: in a system having a known HARQ acknowledgement (ACK) delay, retransmit delay and number of HARQ interlaces, which are each defined in configuration signalling sent to a mobile station and which are a function of at least one of a time division duplexing downlink/uplink (TDD DL/UL) ratio and a frequency division duplexing downlink/uplink (FDD DL/UL) ratio, at a base station, determining the timing for receiving an ACK/NAK from a mobile station based on configuration signalling in response to a previously sent 10 transmission of an encoder packet by the base station; and at a mobile station, determining the timing for receiving one of a transmission and a retransmission of a sub-packet of an encoder packet from a base station based on the configuration signalling in response to a previously sent NAK 15 by the mobile station. 15. The method of claim 14 wherein the HARQ acknowledgement (ACK) delay, retransmission delay and number of HARQ interlaces, which are each defined in configuration signalling sent to a mobile station are a function of portioning of legacy and non-legacy transmission resources. 16. The method of claim 14 wherein a non-legacy transmission resource is a transmission source supported by at least one of: IEEE802.16m, WiMAX evolution and LTE advanced- 17. The method of claim 14 wherein the ACK/NAK and the transmission and retransmissions can be transmitted on one of: a time resource, a frequency resource, and a time and frequency resource. 18. The method of claim 14 wherein: if the TDD DL/UL ratio of sub-frames of a frame are asymmetric; the UL ACKs for corresponding DL transmissions, in which the DL transmissions occur in more DL sub-frames of the frame than UL sub-frames that are available for the UL ACKs, transmitting a plurality of UL ACKs in one UL sub-frame; the DL ACKs for corresponding UL transmissions, in which the UL transmissions occur in more UL sub-frames of the 5 frame than DL sub-frames that are available for the DL ACKs, transmitting a plurality of DL ACKs in one DL sub-frame. 19. The method of claim 14 wherein: if the FDD DL/UL ratio of sub-frames of a frame are asymmetric; the UL ACKs for corresponding DL transmissions, in which the DL transmissions occur in more DL sub-frames of the frame than UL sub-frames that are available for the UL ACKs, transmitting a plurality of OL ACKs in one UL sub-frame; the DL ACKs for corresponding UL transmissions, in 15 which the UL transmissions occur in more UL sub-frames of the frame than DL sub-frames that are available for the DL ACKs, transmitting a plurality of DL ACKs in one DL sub-frame.