TECHNICAL FIELD

[0001] The present invention herein generally relates to the field of wireless communication and particularly relates to method and system for acquiring system information messages in wireless communication systems. The present invention more particularly relates to a method and system for acquiring modified system information messages in a user equipment.

BACKGROUND OF THE INVENTION

[0002] The Long Term Evolution (LTE) is a new terrestrial mobile communication standard currently being standardized by the 3 GPP. The Radio Access Network (RAN) of LTE is named as the Evolved-Universal Mobile Telecommunication Systems Radio Access Network (E-UTRAN). The E-UTRAN physical layer is based on Orthogonal Frequency Division Multiplexing (OFDM). More precisely; the downlink transmission scheme is based on conventional OFDM using a cyclic prefix while the uplink transmission is based on single carrier frequency division multiple access (SC-FDMA) techniques. The OFDM subcarrier spacing is 15 kHz in both uplink and downlink transmission. LTE supports both frequency division duplex (FDD) and time division duplex (TDD).

[0003] System Information (SI) in an LTE system is divided into a number of SystemlnformationBlocks (SIBs) and MasterlnformationBlock (MIB). The MIB includes limited number of most essential and frequently transmitted parameters to acquire other information from the cell. The SI is defined in TS 36.300 as a RRC message carrying a number of SystemlnformationBlocks (SIBs) that have the same periodicity. Each SystemlnformationBlock (SIB) contains a set of related system information parameters. SystemlnformationBlockTypel (SIB1) is transmitted alone, separately from other Si-messages. The MIB message is mapped on a Broadcast Control Channel (BCCH) and carried on Physical Broadcast Channel (PBCH). All other SI messages are carried on a Downlink Shared Channel (DL-SCH) where they can be identified through the SI-RNTI (System Information Radio Network Temporary Identifier).

[0004] SIBs other than SIB1 are carried in SI messages and mapping of SystemlnformationBlocks to SI messages is flexibly configurable by using a schedulinglnformation parameter included in SIB1, with restrictions that each SIB is contained only in a single SI message. Only SIBs having the same scheduling (periodicity) requirement can be mapped to the same SI message. SystemInformationBlockType2 (SIB2) is always mapped to the SI message that corresponds to the first entry in the list of SI messages in the schedulinglnformation parameter.

[0005] In the event that modification of system information is desired, the network can undergo a system information modification procedure by which all UEs communicating with the network are informed of an impending change to the system information. However, in conventional implementations, a wireless communication network conveys only a generalized indicator of an upcoming change of system information to its respective served UEs without providing any further information relating to the information to be changed. As a result, UEs communicating with the network can in some cases be required to re-acquire all system information at each modification regardless of the information to be affected by a given modification. Such a requirement can, in turn, cause losses in UE and/or network performance and power efficiency, an increase in UE implementation complexity, and/or other negative effects on respective UEs and/or an associated network.

[0006] Normally, during System Information Modification procedure, the eNB transmits the modified System Information in the corresponding modification period. The UE is informed through Paging Procedure and/or SIB1 about the SI modification. But the UE does not know which SI has got modified. The UE acquires the new system information immediately from the next SI modification period. This procedure is inefficient since the UE will acquire all SI messages irrespective of whether the SI message has got modified or not.

[0007] In view of the foregoing, there exists a need for a method and system for managing a modification of system information messages associated with a wireless communication network that mitigates at least the above shortcomings. There also exists a need for a method and system for notifying an user equipment on a modification of the system information message in comparison to the previous system information modification cycle. Further, there exists a need to provide a equipment.

[0008] The abovementioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.

OBJECTS OF THE INVENTION

[0009] The primary objective of the present invention is to provide a method and system for notifying a modification in the system information messages to a user equipment in wireless communication systems.

[0010] Another objective of the present invention is to provide a method and system for identifying a modification in the System Information message in comparison to the previous system information modification cycle.

[0011] Another objective of the present invention is to provide a method and system which enables the user equipment to acquire only the modified system information.

[0012] Another objective of the present invention is to provide a method and system for optimizing the system information acquisition procedure.

[0013] Yet another objective of the present invention is to provide a method and system which increases the efficiency of the system information acquisition.

[0014] These and other objectives and advantages of the present disclosure will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

[0015] The various embodiments of the present invention provide a method for communicating updated system information. The method comprises of notifying a modification in a system information to an user equipment and enabling the user equipment to acquire the modified system information.

[0016] According to an embodiment of the present invention, the method of notifying the system information modification by one or more eNBs comprises of, transmitting a system information notification, adding a si-Modified flag to a scheduling information element in a system information block type 1(SIB1), adding a NULL notation to a scheduling information element in a system information block type 1(SIB1), storing the system information in a network, acquiring a modified system information, comparing the modified system information with the stored system information, identifying and updating a modification information in the updated system information, transmitting the updated system information messages to the user equipment, receiving the system information modification notification in the user equipment, storing the system information received from the network, acquiring SIB1 in the succeeding SI modification period,decoding the schedulinglnfoList in the SIB1, processing the system information message in the schedulinglnfoList, identifying the modified system information messages in the schedulinglnfoList, determining a SI window information for the modified system information messages, acquiring the modified system information messages and updating the stored system information.

[0017] According to an embodiment of the present invention, processing the system information messages comprises verifying if the si-modified flag is TRUE and verifying if notation in SIB-Mappinglnfo is NULL.

[0018] According to an embodiment of the present invention, the method further comprises updating the si-Modified flag for the SI message as TRUE in the scheduling Information Element in SIB1 for the modified system information messages and updating the si-Modified flag for the SI message as TRUE in the scheduling information element in SIB1, when a new system information message is added and updating the si-Modified flag for the SI message as TRUE with a NULL notation in the SIB-Mappinglnfo Information Element in the scheduling information element in SIB1 when a system information message is deleted.

[0019] According to an embodiment of the present invention, the user equipment skips acquisition of the system information messages if there is no modification in the system information messages and uses the previously stored information for the SI message.

[0020] According to an embodiment of the present invention, the user equipment replaces the pre-stored system information with the acquired system information for the system information for which si-Modified flag is set as TRUE.

[0021] According to an embodiment of the present invention, the user equipment deletes the pre-stored system information if si-Modified for the SI message is set as TRUE and the SIB-Mappinglnfo Information Element is NULL in the scheduling information element in SIB1.

[0022] According to an embodiment of the present invention, the user equipment uses the pre-stored system information for a plurality of unmodified system information messages.

[0023] Embodiments herein further disclose a system for communicating updated system information. The system comprises a network element having one or more eNB's adapted for transmitting a system information notification, adding a si-Modified flag to a scheduling Information Element in a system information block typel (SIB1), adding a NULL notation to a scheduling Information Element in a system information block typel (SIB1), storing a system information in a network, acquiring a modified system information, comparing the modified system information with the stored system information, identifying and updating a modification in the system information messages and transmitting the updated system information messages in a next modification cycle. The system also comprises a user equipment adapted having at least one module adapted for receiving the system information change notification during preceding previous SI modification period in the user equipments, storing the system information received from the network, acquiring SIB1 in the succeeding system information modification period, decoding the schedulinglnfoList in the SIB1, processing the system information message information in the schedulinglnfoList, identifying the modified system information messages in the schedulinglnfoList, determining the SI window information for the modified sytem information messages, acquiring the SI message and updating the stored system information.

[0024] According to an embodiment of the present invention, the eNB is further adapted for updating "si-Modified" flag for the SI message as TRUE in the schedulinglnfo information element in the SIB1.

[0025] According to an embodiment of the present invention, the eNB is further adapted for updating NULL notation in the SIB-Mappinglnfo Information Element in the schedulinglnfo information element in the SIB1.

[0026] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiment and the accompanying drawings in which:

[0028] FIG. 1 illustrates a block diagram of adding modified System Information ("si-Modified") details to a schedulinglnfo Information Element in SIB1, according to an embodiment of the present invention.

[0029] FIG. 2 is a flowchart illustrating a method of broadcasting the updated System Information in the next modification period to a user device, according to an embodiment of the present invention.

[0030] FIG. 3 is a flowchart illustrating a method for acquiring modified system information messages in a user equipment, according to an embodiment of the present invention.

[0031] FIG. 4 is a block diagram illustrating a sample of the schedulinglnfoList in SystemlnformationBlockTypel (SIB1), according to an embodiment of the present invention.

[0032] Although the specific features of the present disclosure are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the present disclosure.

DETAILED DESCRIPTION OF THE DRAWINGS

[0033] In the following detailed description, a reference is made to the accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.

[0034] The various embodiments of the present invention provide a method and system for communicating updated system information. The method comprises of network element for notifying a modification in a system information to an user equipment and enabling the user equipment to acquire the modified system information.

[0035] According to an embodiment of the present invention, the method of notifying the system information modification by one or more eNBs comprises of, transmitting a system information notification, adding a si-Modified flag to a scheduling information element in a system information block type 1(SIB1), adding a NULL notation to a scheduling information element in a system information block type 1(SIB1), storing the system information in a network, acquiring a modified system information, comparing the modified system information with the stored system information, identifying and updating a modification information in the updated system information, transmitting the updated system information messages to the user equipment, receiving the system information modification notification in the user equipment, storing the system information received from the network, acquiring SIB1 in the succeeding SI modification period, decoding the schedulinglnfoList in the SIB1, processing the system information message in the schedulinglnfoList, identifying the modified system information messages in the schedulinglnfoList, determining a SI window information for the modified system information messages, acquiring the modified system information messages and updating the stored system information.

[0036] The method further comprises processing the system information messages and checks if the si-Modified flag is TRUE. The embodiments herein updates the si-Modified flag for the SI message as TRUE in the scheduling Information Element in SIB1 if there is a modification in the system information or when a new system information message is added. Further, the embodiments herein updates the the si-Modified flag for the SI message as TRUE with a NULL notation in the SIB-Mappinglnfo in the scheduling information element in SIB1 when a system information message is deleted.

[0037] If there is no modification in the system information messages, the user equipment skips acquisition of the system information messages and uses the previously stored information for the SI message.

[0038] The user equipment replaces the pre-stored system information with the acquired system information for the system information for which si-Modified flag is set as TRUE. In another case, the user equipment deletes the pre-stored system information if si-Modified for the SI message is set as TRUE and the SIB-Mappinglnfo Information Element is NULL in the scheduling information element in SIB1.

[0039] The user equipment uses the pre-stored system information for a plurality of unmodified system information messages.

[0040] The eNB is further adapted for updating "si-Modified" flag for the SI message as TRUE in the schedulinglnfo information element in the SIB1.

[0041] The eNB is further adapted for updating NULL notation in the SIB-Mappinglnfo Information Element in the schedulinglnfo information element in the SIB1.

[0042] FIG. 1 illustrates a block diagram of adding modified System Information ("si-Modified") details to the schedulinglnfo Information Element in SIB1, according to an embodiment of the present invention. During System Information Modification procedure, the eNodeB (eNB) 101 transmits the System Information 104 in the SI modification period (N) 103a. The UE 102 is informed through a Paging Procedure 105a about the SI modification . If only SI-3 is modified in the new SI transmission within the SI Modification Period N+l 103b, then the eNodeB transmits the modified System Information in the corresponding modification period i.e. N+l with the Modified Flag Set for SI-3 105b to the UE 102. The UE 102 acquires modified system information (SI-3) immediately from the next modification period i.e. N+l. This procedure is efficient since the UE 102 will acquire only the modified SI messages (i.e. SI-3).

[0043] FIG. 2 is a flowchart illustrating a method of adding and updating modified System Information details to the schedulinglnfo Information Element in SIB1 and broadcasting the updated System Information (modified) in the next modification period, according to an embodiment of the present invention. During the System Information broadcasting (Current System Information) procedure (201), the eNodeB (eNB) transmits the System Information in the corresponding modification period (N) (202).. The eNB checks if the SI Modification Flag for SI messages is set or not (203). If the flag is set, then the eNB initiates system Information Change Notification (paging) to inform all the UE's during the previous SI modification period (204). If the flag is not set, then the method is redirected to step 202.

[0044] The eNB then checks if the SI modification period got completed or not (205). If the SI modification period is completed, the eNB jumps to the next modification period (206) and further checks if the SI Modification Required Flag is set or not (207). If the flag is not set, the eNB continues broadcasting (202) the current system information (201) in the next modification period. If the flag is set, then the eNB acquires new system information (208). The eNB compares the new system information with the stored system information. The eNB identifies if there is a modification in the system information (209) and updates the si-Modified flag in the modified system information messages (210), and updates the si-Modified flag if a new system information message is added (210) and updates the si-Modified flag if a system information message is deleted and notifies NULL in SIB-Mappinglnfo in scheduling information in SIB1 (210). The eNB then updates the modified system information as the current system information (201) transmits the updated system information messages in a succeeding SI modification period (202) to the user equipment.

[0045] According to an embodiment of the present invention, the eNB updates the "si-Modified" flag for the SI message as TRUE in schedulinglnfo Information Element in SIB1 for the System Information messages which have modified. If the new System Information message is added, the eNB updates the "si-Modified" flag for the SI message as TRUE in schedulinglnfo IE in SIB1. The eNB then starts broadcasting the updated System Information in the next SI modification period to the user equipment.

[0046] According to an embodiment of the present invention, the eNB updates the si-Modified flag for the SI message as TRUE with a NULL notation in the SIB-Mappinglnfo in the scheduling information element in SIB1 when a system information message is deleted.

[0047] FIG. 3 is a flowchart illustrating a method for acquiring modified system information messages in user equipment, according to an embodiment of the present invention. The UE receives schedulinglnfo in SIB1 (i.e. UE gets System Information change notification during the previous SI modification period (301). The UE checks whether SI in previous modification period is acquired or not (302). If not, then the UE acquires all the required SI messages (303) and stores the acquired SI messages. If the system information messages are modified, the UE attempts to acquire the system information messages. If the System Information in previous modification period is acquired, the UE retrieves the next SI record from the schedulinglnfoList (i.e. UE acquires SIB1 in the next SI modification period) (304). The UE decodes the schedulinglnfoList in SIB1. The UE then checks whether all the SI records are processed or not (305). If all the SI records are not processed, the UE access SIModifiedFlag in the SI record (306). While processing the SI message information in schedulinglnfoList, the UE checks if "si-Modified" flag is TRUE or not (307). If "si-Modified" flag is set to TRUE, then the UE and determines the SI window information, acquires the SI message (308) and updates the stored System information. If "si-Modified" flag is set to TRUE and NULL is notified in SIB-Mappinglnfo, then the UE deletes the SI message in the stored System information. If the si-Modified" flag is not TRUE, then UE skips the acquisition of the SI message and use the previously stored information for that SI message (309).

[0048] FIG. 4 is a block diagram illustrating a sample of the schedulinglnfoList in SystemlnformationBlockTypel (SIB1), according to an embodiment of the present invention.. The System Information (SI) message 1 record has a periodicity of rf8 (8 radio frames - 80ms) and SIB2, SIB3 are mapped to SI message 1.

[0049] The various embodiments of the present invention provide a method and system for acquiring modified system information messages in user equipment. The method of the present invention notifies the UE via SIB1 as to which System Information message has got modified in comparison to the previous modification cycle giving the UE the opportunity to acquire only the modified System Information thereby optimizing the System Information acquisition procedure. The method of the present invention increases the efficiency of System Information Acquisition because the UE acquires only updated System Information messages and not all the SI messages. The UE uses the stored SI for all the unmodified SI messages.

[0050] According to an embodiment of the present invention, the UE acquires only the modified System Information in the corresponding Si-windows. This reduces power consumption at the UE.

[0051] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.

[0052] Although the embodiments herein are described with various specific embodiments, it will be obvious for a person skilled in the art to practice the disclosure with modifications. However, all such modifications are deemed to be within the scope of the claims. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the embodiments described herein and all the statements of the scope of the embodiments which as a matter of language might be said to fall there between.

CLAIMS

What is claimed is:

1. A method for communicating updated system information, the method comprises of:

notifying a modification in a system information to an user equipment; and enabling the user equipment to acquire the modified system information; wherein notifying the system information modification by one or more eNBs comprises of:

transmitting a system information notification;

adding a si-Modified flag to a scheduling information element in a system information block type 1(SIB1);

adding a NULL notation to a scheduling information element in a system information block type 1(SIB1);

storing the system information in a network;

acquiring a modified system information;

comparing the modified system information with the stored system information;

identifying and updating a modification information in the updated system information;

transmitting the updated system information messages to the user equipment;

receiving the system information modification notification in the user equipment;

storing the system information received from the network;

acquiring SIB1 in the succeeding system information modification period ;

decoding the schedulinglnfoList in the SIB1;

processing the system information message in the schedulinglnfoList;

identifying the modified system information messages in the schedulinglnfoList;

determining a SI window information for the modified system information messages;

acquiring the modified system information messages; and

updating the stored system information.

2. The method of claim 1, wherein processing the system information messages comprises:

verifying if the si-Modified flag is TRUE; and

verifying if notation in SIB-Mappinglnfo is NULL.

3. The method of claim 1, further comprising:

updating the si-Modified flag for the SI message as TRUE in the scheduling Information Element in SIB1 for the modified system information messages;

updating the si-Modified flag for the SI message as TRUE in the scheduling information element in SIB1, when a new system information message is added; and

updating the si-Modified flag for the SI message as TRUE with a NULL notation in the SIB-Mappinglnfo Information Element in the scheduling information element in SIB 1,when a system information message is deleted.

4. The method of claim 1, further comprising:

skipping acquisition of the system information messages if there is no modification in the system information messages and use the previously stored information for the SI message;

replacing the pre-stored system information with the acquired system information for the system information for which si-Modified flag is set as TRUE; and

deleting the pre-stored system information if si-Modified for the SI message is set as TRUE and the SIB-Mappinglnfo Information Element is NULL in the scheduling information element in SIB1.

5. The method of claim 4, wherein the user equipment uses the pre-stored system information for a plurality of unmodified system information messages.

6. A system for communicating updated system information, the system comprising:

a network element having one or more eNB's adapted for:

transmitting a system information notification;

adding a si-Modified flag to a scheduling Information Element in a

system information block typel (SIB1);

adding a NULL notation to a scheduling Information Element in a

system information block typel (SIB1);

storing a system information in a network;

acquiring a modified system information;

comparing the modified system information with the stored system information;

identifying and updating a modification in the system information messages; and

transmitting the updated system information messages in a next modification cycle; and

a user equipment adapted having at least one module adapted for:

receiving the system information change notification during preceding

previous SI modification period in the user equipments;

storing the system information received from the network;

acquiring SIB1 in the succeeding system information modification period;

decoding the schedulinglnfoList in the SIB1;

processing the system information message information in the schedulinglnfoList;

identifying the modified system information messages in the schedulinglnfoList;

determining the SI window information for the modified system

information messages;

acquiring the SI message; and

updating the stored system information.

7. The system of claim 6, wherein the eNB is further adapted for updating "si-Modified" flag for the SI message as TRUE in the schedulinglnfo information element in the SIB1.

8. The system of claim 6, wherein the eNB is further adapted for updating NULL notation in SIB-Mappinglnfo information element in the schedulinglnfo information element in the SIB 1.