ELECTRONIC APPARATUS IN WIRELESS COMMUNICATION SYSTEM, AND MOBILITY MEASUREMENT METHOD TECHNICAL FIELD The disclosure generally relates to the field of wireless communication, and more particularly, to an electronic apparatus in a wireless communication system and a method of performing mobility measurement by a mobile communication terminal. BACKGROUND At present, the following measurement events are defined in a LTE (long-term evolution)/LTE-A (advanced long-term evolution) system: AnAl event, in which a serving cell has a quality higher than an absolute threshold, for turning off an on-going inter-frequency measurement and deactivating a measurement gap. An A2 event, in which a serving cell has a quality lower than an absolute threshold, 15 for turning on inter-frequency measurement and activating a measurement gap. An A3 event, in which a neighbor cell has a quality higher than that of a main servmg cell by an amount higher than an absolute threshold, for a coverage-based inter-frequency/intra-frequency handover. An A4 event, in which a neighbor cell has a quality higher than an absolute 20 threshold, mainly for a load-based handover. An AS event, in which a main serving cell has a quality lower than a first absolute threshold 1 and a neighbor cell has a quality higher than a second absolute threshold 2, for a coverage-based inter-frequency/intra-frequency handover. An A6 event, in which a neighbor cell has a quality higher than that of a secondary 25 servmg cell by an amount higher than an absolute threshold, for a coverage-based inter-frequency secondary carrier adjustment. A B 1 event, in which a neighbor cell in a different system has a quality higher than an absolute threshold, for a load-based handover. A B2 event, in which a serving cell has a quality lower than a first absolute threshold - 1 - Your Ref.: CNPA 130561NOO Our ref.: OP1615-06-0177 Original 1 and a neighbor cell in a different system has a quality higher .than a second absolute threshold 2, for a coverage-based handover. The A II A2 event may be used for turning off or triggering inter-frequency measurement by a terminal. The A3/A5/B2 event may be used for a coverage-based 5 inter-system/intra-system handover. The A6 event may be used for a coverage-based secondary carrier adjustment in a scenario of carrier aggregation. The A4/B 1 event may be used for a load-based inter-system/intra-system handover. 10 15 SUMMARY In a scenario of dual-connection, a terminal is simultaneously connected to two base stations which have no ideal backhaul, such mobility scenario is more complicated than that of a single base station connection or a dual-base station connection with ideal backhaul carrier aggregation. Therefore, embodiments of the disclosure are provided for the above dual-connection scenario. A brief summary of the embodiments of the present disclosure are provided below to provide some basic understanding to some aspects of the present disclosure. It should be understood that the summary is not exhaustive, and is not intended to identify a crucial or important part of the present disclosure or limit the scope of the present disclosure. The only purpose is to give some conception in a simplified manner as a prelude to the detailed 20 description provided later. According to an aspect of the present disclosure, an electronic apparatus in a wireless communication system is provided. The electronic apparatus includes a communication device and a mobility measurement device. The communication device IS configured for performing dual-connection communication with two connection nodes 2~ respectively via different carriers. The mobility measurement device is configured for performing mobility measurement on a connection node of current dual-connection for determining a connection transfer mode, in a case that a service quality of at least one of the current dual-connection nodes is lower than a predetermined level. The mobility measurement is further configured for determining a mode for reporting a result of the mobility 30 measurement based on a measurement condition of at least one of the current dual-connection nodes. - 2- Your Ref.: CNPA l3056JNOO Our ref: 0Pl615-06-0l77 Original According to another aspect of the present disclosure, a method of performing mobility measurement by a mobile communication terminal is provided. The method includes a step of performing mobility measurement on current dual-connection nodes for determining a connection transfer mode in a case that a service quality of at least one of the current 5 dual-connection nodes for the mobile communication terminal communicating in a dual-connection scenario is lower than a predetermined level. The method also includes a step of determining a mode for reporting a result of the mobility measurement based on a measurement condition of at least one of the current dual-connection nodes. The embodiments of the present disclosure are advantageous for improving the 10 efficiency of reporting measurement for dual-connection. BRIEF DESCRIPTION OF THE DRAWINGS The present disclosure can be better understood by referring to the following description taken in conjunction with the accompanying drawings. Same or similar reference 15 characters indicate same or similar parts throughout the accompanying drawings. The accompanying drawings are included in the description together with the following specifications as a part of the description for further illustrating preferred embodiments with examples and explaining the principle and advantages of the present disclosure. In the accompanying drawings: 20 ' 25 Fig. 1 is a block diagram of a configuration example of an electronic apparatus according to an embodiment of the present disclosure; Fig. 2 is a schematic diagram for illustrating connection transfer modes; Fig. 3 is a schematic diagram for illustrating an example of time sequence relation between a T31 0 timer and a TTT timer; Fig. 4 is a schematic diagram for illustrating an example of time sequence relation between TTT timers; Fig. 5 is a schematic diagram for illustrating an example of time sequence relation between a TTT timer and a T31 0 timer; Fig. 6 is a schematic diagram for illustrating an example of time sequence relation - 3 - between a TTT timer and a T31 0 timer; Your Ref.: CNPAI3056JNOO Our ref.: OP 1615-06-0177 Original Fig. 7 is a schematic diagram for illustrating an example of time sequence relation between a TTT timer and a T31 0 timer; Fig. 8 is a schematic diagram for illustrating an exemplary manner of signaling 5 transmission for connection node transfer; 10 Fig. 9 is a schematic diagram for illustrating an exemplary manner of signaling transmission for connection node transfer; Fig. 10 is a schematic diagram for illustrating an exemplary manner of signaling transmission for connection node transfer; Fig. 11 is a schematic diagram for illustrating an exemplary manner of signaling transmission for connection node transfer; Fig. 12 is a flowchart of a process example of a method according to another embodiment of the present disclosure; and Fig. 13 is a block diagram of an exemplary structure of a computer implementing 15 the method and apparatus according to the present disclosure. DETAILED DESCRIPTION OF EMBODIMENTS Embodiments of the invention are described below with reference to the companying drawings. Elements and features described in a companying drawing or an 20 embodiment may be combined with elements and features illustrated in one or more other companying drawings or embodiments in the present disclosure. It should be noted that presentation and explanation of irrelevant components and processes known by those skilled in the art are omitted in the companying drawings and the description for clarity. The technique according to the present disclosure can be applied to various products. 25 For example, a base station can be implemented as an evolved Node B ( eNB) of any types, such as a macro eNB or a small eNB. The small eNB maybe an eNB covering a cell smaller than a macro cell, such as a pico-eNB, a micro-eNB, and a home-eNB (femto-eNB). Alternatively, the base station can be implemented as a base station of any other types, such as a NodeB or a base transceiver station (BTS). The base station may include a main body (also - 4- 5 Your Ref.: CNPA l3056INOO Our ref: OP 1615-06-0177 Original referred to as base station equipment) configured to control wireless communications, and one or more remote radio heads (RRH) arranged at positions different from the main body. Furthermore, each of various terminals to be described below may operate as a base station by temporarily or semi-persistently performing functions of a base station. For example, the electronic apparatus may be implemented as a mobile terminal (such as a smart phone, a tablet personal computer (PC), a laptop PC, a portable game terminal, a portable/dongle mobile router or a digital camera device) or a vehicular terminal (such as a vehicle navigating apparatus). A terminal apparatus 300 can also be implemented as a terminal performing machine-to-machine (M2M) communications (also referred to as a 10 machine-type communication (MTC) terminal). Furthermore, the electronic apparatus 100 may be a wireless communication module (such as an integrated circuit module including a single die) mounted in each of the above terminals. Referring to Fig. 1, an electronic apparatus 100 in a wireless communication system according to an embodiment of the present disclosure includes a communication device 110 15 and a mobility measurement device 120. The communication device 110 IS configured for performing dual-connection communication with two connection nodes respectively via different carriers. For example, as shown in Fig. 2, an electronic apparatus Ul may perform dual-connection communication with two connection nodes Ml and Sl respectively via its 20 communication device. The mobility measurement device 120 is configured for performing mobility measurement on a connection node of current dual-connection for determining a connection transfer mode, in a case that a service quality of at least one of the current dual-connection nodes is lower than a predetermined level. Furthermore, the mobility measurement device 120 2~ is further configured for determining a mode for reporting a result of the mobility measurement based on a measurement condition of at least one of the current dual-connection nodes. In the present disclosure, the term "measurement condition" may include the measurement result per se (such as a reference signal received power (RSRP), and a reference 30 signal received quality (RSRQ), etc.), and may also include other measurement conditions, - 5 - Your Ref.: CNPAI30561NOO Our ref.: OP1615-06-0177 Original such as whether there is a measurement list for a respective connection node, and a state of a respective started T31 0 timer and/or TTT timer, etc. As described with reference to specific embodiments below, the mobility measurement device 120 may determine different modes for reporting a result of the mobility measurement based on a measurement condition, so as to 5 improve the efficiency of reporting measurement of dual-connection. 10 15 According to an embodiment, the mobility measurement may include mobility measurement configured for determining one of the following connection transfer modes: Mode A: disconnecting from one of the current dual-connection nodes to change from a dual-connection state into a single-connection state. Mode B: maintaining connection to one of the current dual-connection nodes, and transferring connection to the other node to a target node, to maintain a dual-connection state. Mode C: disconnecting from both of the current dual-connection nodes, and transferring connection to a target node, to change from a dual-connection state to a single-connection state. Mode D: disconnecting from both of the current dual-connection nodes, and transferring connections to two target nodes, to maintain a dual-connection state. Mode E: maintaining connections to both of the current dual-connection nodes, and adjusting secondary carriers of respective connection nodes. Examples of the connection transfer modes are described more intuitively below 20 with reference to Fig. 2. An apparatus U4, which is in a dual-connection with a macro base station M2 and a small cell base station S4, may disconnect from one of the connection nodes, for example, the small cell base station S4, and maintain connection to the other connection node, for example, the macro base station M2. This connection transfer mode corresponds to the above 25 mentioned mode A. In another example, the mode A may also include a case of disconnecting from the macro base station and maintaining connection to the small cell base station. An apparatus U3, which is in a dual-cmmection with a macro base station Ml and a small cell base station S2, may disconnect from one of the connection nodes, for example, the small cell base station S2, and transfer to a com1ect to a small cell base station S3. This 30 connection transfer mode corresponds to the above mentioned mode B. In another example, - 6 - Your Ref.: CNPA 130561NOO Our ref.: OP1615-06-0177 Original the mode B may also include a case of transferring connection to a source macro base station to a target macro base station. An apparatus US, which is in a dual-connection with the macro base station M2 and a small cell base station SS, may disconnect from both of the macro base station M2 and the 5 small cell base station SS, and transfer to a connect to a macro base station Ml. This connection transfer mode corresponds to the above mentioned mode C. In another example, the mode C may also include a case of transferring the original dual-connection to a connection to a target small cell base station. An apparatus U2, which is in a dual-connection with a macro base station M3 and a I 0 small cell base station S6, may disconnect from both of the macro base station M3 and the small cell base station S6, and transfer to a dual-connection to a macro base station M2 and a small cell base station S7. This connection transfer mode corresponds to the above mentioned mode D. Particularly, for the transfer mode A, no comparison between target nodes is 15 necessary. The transfer may be triggered by, for example, the occurrence of a radio link failure 20 25 • (RLF) over a main carrier of a single node, or a result of mobility measurement of RSRP/RSRQ over a main carrier of the single node being lower than a threshold. For the latter case, a trigger event for the mode A may be distinguished from an E-UTRAN A2 event. For example, a trigger event is defmed specially for the mode A. According to an embodiment, the mobility measurement device 120 may be configured for reporting a mobility measurement result corresponding to the connection transfer of the mode A in a case that a service quality of one of the current dual-connection nodes is lower than a first threshold level. The first threshold level is not higher than a threshold level for triggering an A2 event. With the above configuration, a condition for triggering an inter-frequency measurement by an A2 event is more permissive than the trigger condition for the connection transfer of the mode A. Therefore, the A2 event may be triggered at a time earlier than the connection transfer of the mode A. The first threshold level may be specifically set as required to appropriately determine an interval between the triggering of the A2 event and the 30 triggering of the connection transfer of the mode A . • 7 - Your Ref.: CNPA130561NOO Our ref.: OPI615-06-0177 Original More specifically, an offset threshold may be additional defined, on the basis of A2 event, for deactivating one of the connection nodes by a dual-connection user. For example, information on the offset threshold may be broadcasted from the network to terminals. Alternatively, a set of parameters for a dual-connection user to deactivate one of the 5 connection nodes may be broadcasted from the network to terminals with reference to the definition of parameters for. the A2 event. By the above two exemplary approaches, a report triggering event may be specially designed for the connection transfer of the mode A, or a ~anner for reporting the A2 event can be used to carry a condition (such as an RSRP/RSRQ measurement result) for triggering a report of the connection transfer of the mode A, for the 1 0 network to determine on the deactivation of a node. In the scenario of dual-connection, if an existing manner of measurement report is used, the triggering of coverage-based measurement is challenged in the following aspects. Referring to the example as shown in Fig. 2 again, Ul and U3 perform dual-connection data transmission in a supper dense small cells deployment. Adjacent cells 15 may use different bands in order to avoid strong interference between the small cells. In a case that the small cells is far from a macro base station, when a UE moves to an overlapped region between two small cells of different frequencies and performs inter-frequency measurement, the following situation may occur frequently: both a macro cell and a low power node cell satisfy conditions of A3 to A6 events or B 1 to B2 events with respect to a 20 target measurement small cell, and the events are reported to the macro cell and/or the low power node respectively. However, since the UE is still in the coverage of the macro cell, the connection to the macro cell needs not to be transferred. Therefore, resources are wasted for unnecessarily reporting mobility measurement for comparing between a serving carrier of the low power node and a serving carrier of the macro base station. 25 Furthermore, since US is at an edge of a macro cell, both a target macro cell (Ml) and current dual-connection cells (M2 and S2) satisfY the A3/ AS event. Since U2 is at the edges of two macro cells (M3 and M2) and also the edges of two small cells (S6 and S7), if a source macro cell satisfies an A3/ AS event with respect to both a target macro cell and a target small cell, then the time points for triggering mobility measurement events of main carriers of 30 the two connection nodes of the dual-connection may be different, the connection node transfer operation signaling interaction and data transmission which are performed separately - 8 - 5 10 Your Ref.: CNPA!3056!NOO Our ref.: OP !6 I 5-06-01 77 Original for different reports may be further complicated if the events are reported respectively with a very short time interval. Therefore, it is necessary to define separate trigger events for the scenarios, and simplify the entire operation process for the transmission structure and procedures of user plane data as shown in Fig. 3 for example. According to an embodiment, the mobility measurement device 120 may be configured for performing mobility measurement on the two connection nodes respectively, and determining the triggering of a mobility measurement report according to a comparison of measurement results on measuring objects for the first node and second node of the current dual-connection nodes, in a case that a predetermined condition is satisfied. Next, the manner of determining the triggering of a mobility measurement report according to a comparison of measurement results on measuring objects of the current dual-connection nodes is described with reference to a specific embodiment. In a specific embodiment, the first measuring object for the first node measured by the mobility measurement device 120 may include an inter-frequency inter-system measuring 15 object for the first node and an intra-frequency measuring object for a connection carrier of the first node which are received from the first node. Similarly, the second measuring object for the second node measured by the mobility measurement device 120 may include an inter-frequency inter-system measuring object for the second node and an intra-frequency measuring object for a connection carrier of the second node which are received for the 20 second node. For example, the measurement objects of different connection nodes may be determined according to inter-frequency measurement/inter-system measurement lists for respective nodes. Accordingly, the mobility measurement device 120 may be configured for performing the mobility measurement based on the first measuring object and the second 25 measuring object respectively, comparing a measurement result of a first measuring object with a measurement result of a second measuring object to determine whether a measurement reporting condition is satisfied, and reporting the measurement result and/or a measurement comparison result of the measuring objects if a carrier of the first node or the second node satisfies the measurement reporting condition. The measurement result and/or the 30 measurement comparison result may be reported only to the node corresponding to the measurement object, or only to a macro node, or to both of the connection nodes. - 9 - Your Ref.: CNPA13056JNOO Our ref.: OP16!5-06-0!77 Original In the scenario of dual-connection, the network may configure a tetminal apparatus to perform inter-frequency measurement on any connection nodes having any carriers that satisfY a condition for reporting the A2 event. On the other hand, an intra-frequency measurement result of a camer of a first connection node may be considered as an 5 inter-frequency measurement result of a second connection node, and an inter-frequency (inter-system or intra-system) measurement result of the first connection node may also be considered as an inter-frequency measurement result of the second connection node. Similarly, an intra-frequency measurement result of a carrier of the second connection node may be considered as an inter-frequency measurement result of the first connection node, and vice 10 versa. With the embodiment, the measurement result is appropriately reported by referring to the mobility measurement results of both of the connection nodes, which may avoid reporting repeated information in a case that the measurement objects for the two connection nodes include a same target node. Therefore, urmecessary frequent reports of the A3/A4/A5/A6/Bl/B2 event can be avoided, thereby the number of triggering of measurement 15 reports in the scenario of dual-connection can be optimized. According to another specific embodiment, the mobility measurement device 120 may be configured for comparing a measurement result of the first node with a measurement result of the second node to decide whether a triggering condition of an E-UTRAN A3/A4/A5/Bl/B2 event is satisfied in a case that the first node satisfies at least one of the 20 following conditions: 25 1.1) at least one of the first node and the second node satisfies the triggering condition of the A2 event. 1.2) for the first node, there is no measuring object for inter-frequency measurement or inter-system measurement. 1.3) a T31 0 timer started for a main carrier of the first node exceeds a predetermined time limit and an A3/ A4/ AS/B 1/82 TTT timer for the first measuring object has not been started yet, or the TTT timer has been started but is turned off within a predetermined time limit. Here, the measurement result of a node refers to a result of mobility measurement 30 performed for the node, which may include a result of measurement on a signal transmitted by a measuring object (such as the first measurement object) related to the node. As mentioned - 10- 5 Your Ref.: CNPA 13056INOO Our ref.: OP1615-06-0177 Original above, the measuring object of the node may be detc1mined based on information on an inter-frequency inter-system measuring object regarding the node and information on an intra-frequency measuring object for a connection carrier of the node which are received from the node. Regarding the above condition 1.1 ), the comparison between the measurement result of the first node and the measurement result of the second node may be performed directly in a case that one of the dualcconnection nodes has a service quality lower than a threshold for the A2 event. Regarding the above condition 1.2), the comparison of measurement results may be 10 performed directly in a case that, for example, one of the dual-connection nodes does not have a mobility measurement list, so that the measurement result of the measuring object of the other node can be used. Regarding the above condition 1.3), the comparison of measurement results may be performed directly in a case that one of the dual-connection nodes has a high possibility of 15 link failure and there is no candidate target node, so that the measurement result of the measuring object of the other node can be used. Accordingly, the comparison of measurement results between nodes may be stopped according to a predetermined condition. According to a specific embodiment, the mobility measurement device 120 may be configured for stopping comparison with the measurement 20 result of the second node, and turning off a corresponding A3/ A4/ A5/B 1/B2 TIT timer which has been triggered, the comparison of measurement results of a main carrier of the first node is limited to comparison with frequency points of the first measuring objects, in a case that the first node satisfies at least one of the following conditions: 2.1) a main carrier of the first node satisfies a condition for triggering report of an 25 A 1 event; and 30 2.2) a T31 0 timer for a main carrier of the first node is turned off before the T31 0 timer expires, or an A3/ A4/ A5/B 1/B2 TTT timer related to the first measuring object is started before a predetermined time limit expires from the start of the T31 0 timer, or the TTT timer has been started and operation time of the TTT timer exceeds a predetermined limit. Regarding the above condition 2.1 ), since the service quality of the node IS · II - 5 Your Ref.: CNPAl3056INOO Our ref.: OP1615-06-0177 Original recovered, the comparison with measurement result of the other node may be stopped. Regarding the above condition 2.2), since the possibility oflink failure of the node is small or a candidate target node is likely to exist, the comparison with measurement result of the other node may be stopped. Particularly, according to an embodiment, the mobility measurement device 120 is configured for performing, for mobility measurement corresponding to a connection transfer of the mode E, the mobility measurement and report only for a frequency point contained in a measuring object of inter-frequency measurement or inter-system measurement of each of the current dual-connection nodes, thereby ensuring proper handover to a secondary carrier in the 10 node without unnecessary reporting. Furthermore, while a TTT timer for a single node is started for triggering a report of a traditional handover event, another channel quality monitoring procedure, i.e., RLF monitoring is also performed. For example, referring to Fig. 3, the TTT timers (for example, TTT timers 1-4) started for individual nodes may have different time relations with a RLF 15 T31 0 timer. Furthermore, certain time dependency may exist among different nodes, which may be helpful for determining a measurement report corresponding to which mode of transfer to be triggered. According to an embodiment, the mobility measurement device 12 may be configured for directly triggering a measurement result report and/or measurement 20 comparison result report corresponding to connection transfer of the mode C in a case that a first node of the current dual-connection nodes satisfies a condition for triggering report of the A3/A4/A5/Bl/B2 event, and the A3/A4/A5/Bl/B2 TTT timer and/or a T3l 0 timer started for a second node of the current dual-connection nodes satisfies a predetermined condition. In other words, in a case that the first node satisfies a condition of connection 25 transfer, if the timer for the second node satisfies a predetermined condition (such as specific conditions described with reference to specific embodiment below), it is unnecessary to wait for expiration of a timer for the second node to perform the measurement result report corresponding to the connection transfer of the mode C. The report may indicate that the first node satisfies a condition for transferring to a target node and the second node may be 30 disconnected from. Therefore, the system may decide, according to the measurement result, to disconnect from both of the current dual-connection nodes and transfer to the target node, - 12 - 5 Your Ref.: CNPA130561NOO Our ref.: OP1615-06-0177 Original thereby changing from a dual-connection state to a single connection state. With this configuration, the complicity of reporting measurement results may be reduced. In the following, an example of the above predetermined condition is described with reference to specific embodiments. According to a specific embodiment, the measurement result report corresponding to the mode C is directly performed if the follow conditions are satisfied: 3.1) the first node first satisfies a condition for triggering report of the A3/ A4/ AS/B 1/B2 event; 3.2) at this time, the expiration-waiting-time of an A3/ A4/ ASIB l/B2 TTT timer for a I 0 main carrier of the second node is less than a predetermined threshold; and 15 3.3) a measuring target node of the first node is the same as that of the second node. Herein, the term "expiration-waiting-time" refers to a difference between a current time and an expected expiration time of a timer. In other words, the shorter the expiration-waiting-time is, the closer to the expiration of a timer. If the above condition 3.1) is satisfied, it is indicated that the first node has an available target node for transfer (which may be an inter-system or intra-system node). If the above condition 3.2) is satisfied, it is indicated that the second node is highly possible to have an available target node for transfer. Referring to Fig. 4, the condition 3.2) is satisfied if T8 -TA"SLI.TTr, where the current time is the time when a TTT timer TTTt.for the 20 first node is expired (i.e., the time point TA in Fig. 4), and the expiration-waiting-time of a TTT timer TTT B for the second node is denoted by T B· If the above condition 3.3) is satisfied, it is indicated that the connection is to be transferred to the same target node even if the TTT timer for the second node expires. Therefore, if the above conditions are satisfied, the measurement result report 25 corresponding to the connection transfer of the mode C may be directly performed without waiting for the expiration of the timer for the second node. Therefore, the system may decide, according to the measurement result, to disconnect fi"om both of the current dual-connection nodes and transfer to the target node. In another embodiment, a measurement result report corresponding to the mode C is - 13 - 5 Your Ref.: CNPAl3056INOO OUI· ref.: OP1615-06-0 177 Original directly performed and the report indicates that the target node for transfer is a target node of the first node in a case that the following conditions are satisfied: 4.1) the first node first satisfies a condition for triggering report of an A3/A4/A5/Bl/B2 event; 4.2) at this time, the expiration-waiting-time of an A3/ A4/ A5/Bl/B2 TTT timer for a main carrier of the second node is less than a predetermined threshold; and 4.3) at this time, the expiration-waiting-time of a T310 timer for the second node is not greater than that of the TTT timer by a predetermined threshold or more. If the above condition 4.1) is satisfied, it is indicated that the first node has an 10 available target node for transfer. 15 20 25 If the above condition 4.2) is satisfied, it is indicated that the second node is highly possible to have an available target node for transfer. Referring to Fig. 5, the condition 4.2) is satisfied if a time T A when a TTT timer TTT A for the first node is expired and the expiration-waiting-timeT 8 of a TTT timer TTT B for the second node satisfY T 8 -TA'SAnTIf the above condition 4.3) is satisfied, it is indicated that even if the TTT time for the second node expires, a link faill!re is highly possible to occur in a time not sufficient for completing the connection transfer. Referring to Fig. 5, the condition 4.3) is satisfied if Tc-T8 «:AT3 10, where the expiration-waiting-time of the T310 timer for the second node is denoted as T c- Therefore, in a case that the above conditions are satisfied, the measurement result repmi corresponding to the connection transfer of the mode C may be directly performed without waiting for the expiration of the TTT timer or the T310 timer for the second node. Therefore, the system may decide, according to the measurement result, to disconnect from both of the current dual-connection nodes and transfer to the target node. In another embodiment, a measurement result report corresponding to the mode C is directly performed and the report indicates that the target node for transfer is a target node of the first node, in a case that the following conditions are satisfied: 5.1) the first node first satisfies a condition for triggering report of an A3/A4/A5/Bl/B2 event; . 14. 5 Your Ref.: CNPA l3056INOO Our ref.: OP I 6!5-06-0 !77 Original 5.2) at this time, the expiration-waiting-time of a T31 0 timer for the second node is less than a predetermined threshold. If the above condition 5.1) is satisfied, it is indicated that the first node has an available target node for transfer. If the above condition 5.2) is satisfied, it is indicated that a link failure is likely to occur to the second node soon. Referring to Fig. 6, the condition 5.2) is satisfied if Tc-TA"Sl>'n 10, where the expiration-waiting-time of the T310 timer for the second node is denoted as Tc. Therefore, in a case that the above conditions are satisfied, the measurement result 10 report corresponding to the connection transfer of the mode C may be directly performed without wait for the expiration of the TTT timer or the T31 0 timer for the second node. Therefore, the system may decide, according to the measurement result, to disconnect from both of the current dual-connection nodes and transfer to the target node of the first node. In the above specific embodiments, the thresholds l>TTr, l>r31o, .t.'n10 may be set 15 specifically according to requirements. For example, the time thresholds may be set by referring to the time needed for performing the connection transfer, and may be notified to the mobility measurement device by a serving carrier of the connection node via a broadcast message or a dedicated RRC/MAC. Embodiments of reporting directly without waiting for the expiration of a ti~er for 20 the second node in a case that the measurement condition satisfies a certain condition are described above. In another embodiment, the mobility measurement device 120 may be configured for waiting for the expiration of an A3/A4/A5/Bl/B2 TTT timer for a second node in a case that a first node of the current dual-connection nodes satisfies a condition for triggering report of an A3/A4/A5/Bl/B2 event, and the A3/A4/A5/Bl/B2 TTT timer started 25 for the second node of the current dual-connection nodes and a T31 0 timer started for the first node and/or the second node satisfy a predetermined condition. In other words, in a case that a first node satisfies a condition of connection transfer, if timers of the first node and the second node satisfY a certain condition (such as the condition described below with reference to specific embodiments), the expiration of the 30 timer for the second node is waited for. Therefore, the system can determine the connection • 15 • Your Ref.: CNPI\ 13056INOO Our ref.: OP1615-06-0177 Original transfer mode based on measurement results of both of the nodes. With the embodiment, it can be ensured to determine the connection transfer mode more properly based on measurement result of both the nodes in certain cases. According to a specific embodiment, the expiration of a TTT timer for the second 5 node is waited for in a case that the condition for triggering the report of an A3/ A4/ A5/B 1/B2 event is satisfied for the first node and the following conditions are satisfied: 6.1) the expiration-waiting-time of the A3/A4/A5/Bl/B2 TTT timer started for a main carrier of the second node is less than a predetermined threshold; and 6.2) the expiration-waiting-time of the T31 0 timer started for the first node and/or 10 the second node is greater than the expiration-waiting-time of the TTT timer for the second node by a predetermined threshold or more. If the above condition 6.1) is satisfied, it is indicated that the second node is highly possible to have an available target node for transfer. For example, referring to Fig. 7, the condition 6.1) is satisfied because the expiration time TA of the timer TTTA for the first node 15 and the expiration-waiting-time T 8 of the TTT timer TTT 8 for the second node satisfY the condition Ts-TA:SATTT· If the above condition 6.2) is satisfied, it is indicated that a link failure will not occur soon to the first node and/or the second node. For example, referring to Fig. 7, the condition 6.2) is satisfied because the expiration time Tc of a T31 0 timer (which may be started for the 20 first node and/or the second node) satisfies the condition Tc-T 8:SATTT· Furthermore, in a case that the above conditions for waiting for the expiration of a TTT timer for the second node are satisfied, if the TTT timer for the second node is turned off due to a fact that the channel quality of the second node is recovered during the waiting for the expiration of the TTT timer, the measurement result report corresponding to the mode B 25 may be performed for the measurement triggering event of the first node. In other words, in a case that the first node satisfies the condition of connection transfer, if the service quality of the second node is recovered, the report may indicate that the first node satisfies a condition for transferring to the target mode and connection to the second node may be maintained. Therefore, the system may decide, according to the measurement 30 result, to maintain the connection to the second node of the current dual-connection nodes and - 16- Your Ref: CNPA 130561NOO Our ref.: OPI615-06-0177 Original transfer the connection to the first node to connection to the target node of the first node, thereby maintaining a dual-connection state. Furthermore, in a case that the above conditions for waiting for the expiration of a TTT timer for the second node are satisfied, if the TTT timer for the second node expires, 5 corresponding reporting manners can be determined based on the following measurement conditions: 7.1) in a case that target nodes of TTT events for main carrier measurement of the first node and the second node are different, a measurement result report corresponding to the mode D is performed, or a measurement result report corresponding to the mode C is 10 performed with a target node of a macro node serving as the target node for transfer. 7.2) in a case that target nodes of TTT events for main carrier measurement of the first node and the second node are the same, performing a measurement result report corresponding to the mode C. Regarding the case 7 .l ), since the two nodes have different available target nodes for 15 transfer, the report may indicate that each of the first node and the second node satisfies a condition for transferring to a respective target node. The system may decide, according to the measurement result, to disconnect from both of the dual-connection nodes, and transfer to the two target nodes, thereby maintaining a dual-connection state. Alternatively, the system may decide, according to the measurement result, to disconnect from both of the dual-connection 20 nodes, and transfer to a target node of a macro node, thereby maintaining a single-connection state. Regarding the above case 7.2), since the two nodes have the same available target node for transfer, the report may indicate that both the first node and the second node satisfy the condition for transferring to the same target node. Therefore, the system may decide, 25 according to the measurement result, to disconnect from both of the current dual-connection nodes and transfer to the target node, thereby changing from a dual-connection state to a single-connection state. Furthetmore, according to an embodiment, the condition for waiting for the expiration of the TTT timer for the second node may further include: the measurement trigger 30 reporting event for the second node is a coverage-based mobility trigger reporting event. In - 17 - Your Ref.: CNPA I 3056JNOO Our ref.: OPI 615-06-0177 Original other words, it is required that the measurement on the second node is coverage-based mobility measurement for waiting for the expiration of the TTT timer for the second node after the expiration of the TTT timer for the first node, while the measurement of the first node may be coverage-based mobility measurement or load-based mobility measurement. 5 With this configuration, it is avoid that a report of coverage-based measurement waits for a report of load-based measurement, thereby having a more reasonable mobility measurement reporting manner. In addition to the above measurement conditions described with reference to the above embodiments, there may be another condition that both of the dual-connection nodes 10 satisfY a condition for triggering a report. According to an embodiment, the mobility measurement device 120 may be configured for, in a case that main carriers of both of the current dual-connection nodes satisfY a condition for triggering report of an A3/ A4/ A5/B l/B2 event, not transferring the connection to the two nodes, but performing a measurement result report corresponding to the mode B according to a priority order, or performing a 15 measurement result report corresponding to the mode D in order to decide a preferred transferring node by the network. In other words, the report may indicate that one of the nodes satisfies the condition for transferring to the target node, and connection to the other node may be maintained. Therefore, the system may decide, according to the measurement result, to maintain connection to which one of the current dual-connection nodes and transfer the 20 connection to the other node to a target node, thereby maintaining a dual-connection state. For the other node, measurement result of the other node may be reported after a certain time or after receipt of a node transferring command from the network. This configuration is advantageous for reducing the complicity of measurement report. Specifically, the priority order may be determined according to one or more of the 25 following principles: 8.1) the one having a worse channel quality of source node is prior; 8.2) the one having a better signal of target node is prior; 8.3) a coverage-based measurement event is prior to a load-based measurement event; 30 8.4) a node whose T310 timer expires earlier is prior; and - 18 - 8.5) a macro node is prior to a low power node. Your Ref.: CNPAI30561NOO Our ref.: OP 1615-06-0177 Original With the principles 8.1) and 8.2), the transfer mode is selected according to channel quality, which may achieve better channel quality by the node transfer. With the principles 8.3) and 8.5), it is ensured that more important node has higher priority to be transferred. With the 5 principle 8.4), it is ensured that a node that is more likely to have link failure has higher priority to be transferred. With this configuration, the report may be performed according to the channel quality or the importance of nodes, thereby having a more reasonable mobility measurement reporting manner. Furthermore, considering that a macro node is mainly for maintaining the network I 0 connection and a low power node is mainly for data distribution, preferably, load-based measurement report can be performed mainly for a low power node and coverage-based measurement report can be performed for both of the connection nodes. 15 Therefore, according to an embodiment, the mobility measurement device 120 IS configured for reporting a load-based event only for a low power node. Particularly, in a case that a measurement report corresponding to the connection transfer mode C and the connection transfer mode D (i.e., disconnecting from both of dual-connection nodes and transferring the connection to one or more target nodes) occurs in various temporal relations combinations, the mobility measurement device 120 may be configured for reporting a new report triggering event or reporting by combining traditional 20 A3/A4/A5/Bl/B2 events. Furthermore, the mobility measurement device 120 may report in various manners. For example, it is possible to report measurement results of connection nodes to respective connection nodes (i.e., to report measurement result of the first node to the first node and report measurement result of the second node to the second node), or report measurement results of all connection nodes to both of the connection nodes (i.e., to report 25 measurement results of the first and second nodes to both of the first and second node). 30 Furthermore, it is possible to report measurement results of both nodes only to a macro node, or report measurement results of both nodes to the macro node while reporting a measurement result of a main carrier of a low power node to the low power node, as will be described with reference to Fig. 8 to Fig. 11 below. According to an embodiment, the mobility measurement device 120 is configured for, if radio link failme occurs to a node of the current dual-connection nodes before receipt of . 19- Your Ref.: CNPA130561NOO Our ref.: OP1615-06-0177 Original a node transfer notice and a node transfer event report is performed for the node, reporting to the network via the other node of the current dual-connection nodes after waiting for over a predetermined time limit, and waiting for transfer notice signaling sent from the network via the other node within the time limit. Alternatively, report can be made directly to tbe other 5 node, and node transfer operation is made based on a notice from the other node. Furthermore, the node for reporting a measurement result and rece1vmg a confirmation for connection transfer may be determined according to a state of a T31 0 timer or TTT timer started for a connection node. According to an embodiment, the mobility measurement device 120 may be 1 o configured for sending a measurement report and receiving a confirmation for connection transfer via a first node and/or a second node of the current dual-connection nodes, that is, sending a measurement report and receiving a confirmation for connection transfer via any one or both of the two nodes, in the following case: 9.1) the expiration-waiting-times of T310 timers for the first node and the second 15 node are both greater than a predetermined threshold; or 9.2) for the first node and the second node, the expiration-waiting-time of a T310 timer is greater than that of a TTT timer by a predetermined threshold or more. As mentioned above, the expiration-waiting-time is a difference between a current time and an expected expiration time of a timer. Below, it is assumed that the current time is 20 the expiration time of the TTT timer for the first node, and T31 0 A denotes the expiration-waiting-time of the T31 0 timer for the first node, T31 08 denotes the expiration-waiting-time of the T31 0 timer for the second node, and TTT 8 denotes the expiration-waiting-time of the TTT timer for the second node. If the conditions in the case 9.1) are satisfied, that is, T310A;::>:,i',A and T3108 ;::>:6n, it 25 is indicated that no link failure will occur soon to any of the two connection nodes. Therefore, the sending of a measurement report and reception of a confirmation for connection transfer may be performed by any one or both of the connection nodes. If the conditions in the case 9.2) are satisfied, that 1s, T310A-TTT 8 ;::>:6 'A and T31 Ow TTT 8 ;::>:t.'8 , it is indicated that there may be sufficient time between the determination 30 of available target node for transfer and occurrence of link failure. Therefore, the sending of a -20- Your Ref.: CNPA130561NOO Our ref.: OP 1615-06-0177 Original measurement report and reception of a confirmation for connection transfer may be performed by any one or both of the connection nodes. In another embodiment, the mobility measurement device 120 may be configured for sending a measurement report and receiving a confirmation for connection transfer via a 5 first node of the current dual-connection nodes in the following case: 10.1) the expiration-waiting-time of a T31 0 timer for the first node is greater than a predetermined threshold, and the expiration-waiting-time of a T31 0 timer for a second node of the current dual-connection nodes is less than a predetermined threshold; or 1 0.2) for the first node, the expiration-waiting-time of a T31 0 timer is greater than I 0 that of a TTT timer by a predetermined threshold or more, and for the second node, the expiration-waiting-time of a T31 0 timer is not greater than that of a TTT timer by a predetermined threshold or more. If the conditions in the case 10.1) are satisfied, that is, T310A~ /1A and T310s< /13, it is indicated that no link failure will occur soon to the first nodes, while a link failure may 15 likely occur soon to the second node. Therefore, the sending of a measurement report and reception of a confirmation for connection transfer may be performed by the first nodes. If the conditions in the case 10.2) are satisfied, that is, T310A- TITs~ 11'A and T31 08 - TTT 8 < 11' 8 , it is indicated that there may be sufficient time between the determination of available transfer target node and occurrence oflink failure for the first node, 20 while there may not be sufficient time between the determination of available transfer target node and occurrence of link failure for the second node. Therefore, the sending of a measurement report and reception of a confirmation for connection transfer may be performed by the first node. Similarly, the mobility measurement device 120 may be configured for sending a 25 measurement report and receiving a confi1mation for connection transfer via the second node of the current dual-connection nodes in the following case: 30 11.1) the expiration-waiting-time of a T31 0 timer for the second node is greater than a predetermined threshold, and the expiration-waiting-time of a T31 0 timer for the first node of the current dual-connection nodes is less than a predetem1ined threshold; or 11.2) for the second node, the expiration-waiting-time of a T31 0 timer is greater . 21 - Your Ref.: CNPA 130561NOO Our ref.: OP 1615-06-0 I 77 Original than that of a TTT timer by a predetermined threshold or more, and for the first node, the expiration-waiting-time of a T3l 0 timer is not greater than that of a TTT timer by a predetermined threshold or more. In another embodiment, the mobility measurement device 120 may be configured 5 for sending a measurement report or receiving a confirmation for connection transfer via both of a first node and a second node of the current dual-connectionnodes in the following case: 12.1) the expiration-waiting-times of T310 timers of the first node and the second node are both less than a predetermined threshold; or 12.2) for the first node and the second node, the expiration-waiting-time of a T31 0 I 0 timer is not greater than that of a TTT timer by a predetermined threshold or more. If the conditions in the case 12: 1) are satisfied, that is, T31 0 A