JP2010177892A - Wireless communication terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless communication terminal capable of reducing power consumption when the wireless line is suspended and is in communication state with a network connection maintained. <P>SOLUTION: When the wireless communication terminal capable of corresponding to the WiMAX (Worldwide Interoperability for Microwave Access System) and the EVDO system (Evolution Data Only system) uses the WiMAX system, and the WiMAX system maintains the network connection transits to a state suspending the wireless communication line for a predetermined time period, a system hand-over from the WiMAX system to the EVDO system is conducted. After the system hand-over from the WiMAX system to the EVDO system, communicating with the EVDO system for the predetermined time period causes the system handover from the EVDO system to the WiMAX system. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wireless communication terminal compatible with a plurality of wireless communication systems.

Usually, a wireless communication terminal is configured to support any one wireless communication system. However, a plurality of wireless communication systems are connected to a single wireless communication for the purpose of providing a stable and highly functional service. A technology that can be used in a terminal has also been proposed.
In a wireless communication terminal compatible with such a plurality of wireless communication systems, conventionally, which wireless communication system performs standby depends on the reception sensitivity of the wireless communication system, as disclosed in Patent Document 1, In the first place, all wireless communication systems waited.

  In recent years, wireless communication systems such as a WiMAX (Worldwide Interoperability for Microwave Access) system and a CDMA2000 1x EVDO system (hereinafter referred to as an EVDO system) have been put to practical use as a communication system for wireless communication terminals. The WiMAX system is a wireless communication system standardized by IEEE (Institute of Electrical and Electronic Engineers) 802.16, and can communicate at higher speed than before. On the other hand, an EVDO system has been conventionally used as a wireless communication system used for data communication.

  In the following, a dormant state in which a wireless communication terminal capable of supporting two wireless communication systems of the WiMAX system and the EVDO system pauses the wireless line while maintaining the network connection (hereinafter referred to as a standby state in the WiMAX system and the EVDO system). ), The difference in power consumption between when the WiMAX system is used and when the EVDO system is used will be described. During the standby state, the WiMAX system is in an idle state or a sleep state, and the EVDO system is in an idle state.

  FIG. 1 is a diagram illustrating transmission / reception timing of the wireless communication terminal in the standby state. As shown in the transmission timing of FIG. 1, in the WiMAX system, the wireless communication terminal periodically checks with the base station at a minimum 128-sec interval to keep the terminal alive in the standby state (Keep Alive). Send. On the other hand, in the EVDO system, the wireless communication terminal does not perform the terminal alive operation (Keep Alive) operation in the base station unless requested by the base station in the standby state. Do not do.

  In the WiMAX system, the wireless communication terminal transmits to the base station when the base station parameter is changed (the area of the terminal is moved). In the EVDO system, the wireless communication terminal is a fixed distance from the last communicating base station. When handoff is performed to a base station far away from the above, transmission is performed to the base station. As shown in FIG. 2, it is assumed that the WiMAX system is generally narrower than the EVDO system as the coverage area of one base station. From this, it is assumed that when the terminal moves, the WiMAX system needs to transmit with the base station by “area crossing”.

Further, for example, as shown by the reception timing in FIG. 1, the reception interval of incoming calls is about 3 sec in the WiMAX system, whereas it is 5.12 sec in the EVDO system, and the reception interval of the WiMAX system is that of the EVDO system. Shorter than the reception interval.
In addition, the power consumption for one incoming call reception is larger in the WiMAX system than in the EVDO system.

  From the above, it can be seen that during the standby state, the WiMAX system consumes more power than the EVDO system.

JP 2003-101474 A

  As described above, when there is a difference in power consumption between the two wireless communication systems in the standby state, the wireless communication terminal corresponding to the two wireless communication systems can receive only the reception sensitivity as disclosed in Patent Document 1. When selecting a wireless communication system that performs standby, a wireless communication system with high power consumption may be selected during standby. In addition, when waiting in both wireless communication systems, much power is consumed accordingly.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a wireless communication terminal capable of reducing power consumption when a wireless line is suspended while maintaining a network connection. There is to do.

  In order to achieve the above object, the wireless communication terminal of the present invention periodically performs reception processing for incoming call monitoring and transmission for maintaining the network connection in a state where the wireless line is suspended while maintaining the network connection. Corresponding to the first wireless communication system that needs to perform processing and the second wireless communication system that does not need to perform transmission processing for maintaining the network connection in a state where the wireless line is suspended while maintaining the network connection When the wireless communication terminal is using the first wireless communication system, the wireless communication terminal is in a state where the wireless line is suspended while maintaining the network connection. And a control unit that controls to perform system handover from the first wireless communication system to the second wireless communication system when the transition is made. To.

  The control unit transitions to a state in which the first wireless communication system is in a state where a wireless line is suspended while maintaining network connection, and after the first predetermined time has elapsed, the first wireless communication system performs the second wireless communication from the first wireless communication system. It is preferable to perform control so that the system is handed over to the system, and it is preferable that the first predetermined time depends on an execution application.

  Further, it is preferable that the control unit performs control so that a system handover is performed from the first radio communication system to the second radio communication system when the radio field intensity of the second radio communication system is equal to or greater than a threshold value.

  In addition, when the control unit performs system handover from the first radio communication system to the second radio communication system and then performs communication for a second predetermined time in the second radio communication system, the second radio communication system It is preferable to perform control so that a system handover is performed to the first wireless communication system, and it is preferable that the second predetermined time depends on an execution application.

  Further, it is preferable that the control unit performs control so that a system handover is performed from the second radio communication system to the first radio communication system when the radio field intensity of the first radio communication system is equal to or greater than a threshold value.

  The present invention performs system handover to a wireless communication system with low power consumption when transitioning to a state in which the wireless line is suspended while maintaining the network connection, so that the wireless line is suspended while maintaining the network connection. Power consumption during the state can be reduced.

It is a figure which shows the transmission / reception timing of the radio | wireless communication terminal in a standby state. It is a figure explaining the communication area of a WiMAX system and EVDO system. It is a figure which shows the structural example of the radio | wireless communication terminal which concerns on embodiment of this invention. It is a flowchart explaining the operation | movement of the inter-system handover when it changes to the standby state by a WiMAX system. It is a flowchart explaining the operation | movement of the handover between systems when it changes to the communication state by EVDO system. It is a figure which shows an example of a standby state handover (HO) timer value and a communication state handover (HO) timer value.

Embodiments of the present invention will be described with reference to the drawings.
As described above, in a wireless communication terminal capable of supporting two wireless communication systems of the WiMAX system and the EVDO system, a dormant state in which a wireless line is suspended while acquiring an IP (Internet Protocol) address and maintaining a network connection (Hereinafter referred to as a standby state in the WiMAX system and the EVDO system), there is a difference in power consumption when the WiMAX system is used and when the EVDO system is used.

  As shown in the transmission timing of FIG. 1, in the WiMAX system, the wireless communication terminal periodically checks with the base station at a minimum 128-sec interval to keep the terminal alive in the standby state (Keep Alive). On the other hand, in the EVDO system, the terminal alive check (Keep Alive) operation in the base station is not performed unless there is a request from the base station in the standby state. Absent.

  In the WiMAX system, the wireless communication terminal transmits to the base station when the base station parameter is changed (the area of the terminal is moved). In the EVDO system, the wireless communication terminal is a fixed distance from the last communicating base station. When handoff is performed to a base station far away from the above, transmission is performed to the base station. As shown in FIG. 2, it is generally assumed that the WiMAX system is narrower than the EVDO system as the coverage area of one base station. Therefore, when the terminal moves, the WiMAX system is “cross-area”. Therefore, it is assumed that there are many situations in which transmission with the base station must be performed.

Further, for example, as shown by the reception timing in FIG. 1, the reception interval of incoming calls is about 3 sec in the WiMAX system, whereas it is 5.12 sec in the EVDO system, and the reception interval of the WiMAX system is that of the EVDO system. Shorter than the reception interval.
In addition, the power consumption for one incoming call reception is larger in the WiMAX system than in the EVDO system.

  Therefore, it can be seen that the WiMAX system consumes more power than the EVDO system during the standby state.

  FIG. 3 is a diagram illustrating a configuration example of the wireless communication terminal according to the embodiment of the present invention. The wireless communication terminal 100 shown in FIG. 3 includes a WiMAX RF unit (wireless communication unit) 20 that communicates with a base station using a WiMAX system (first wireless communication system), and a base station connected to an EVDO system (second wireless communication system). EVDO RF unit (wireless communication unit) 10 that performs communication, system control unit 30 (control unit) that controls the entire terminal, display unit 40, system storage unit 50 that stores various data values, and key input unit 60 It has. The system control unit 30 (control unit) includes a data communication unit 31, a handover execution unit 32, a handover determination unit 33, an application determination unit 34, an EVDO communication unit 35, and a WiMAX communication unit 36. The system storage unit 5 includes an application-specific handover timer storage unit 51 and a handover reception sensitivity threshold storage unit 52.

  The operation when a wireless communication terminal capable of supporting two wireless communication systems of the WiMAX system and the EVDO system according to the present invention performs handover between systems will be described below together with the functions of each component of the wireless communication terminal described above.

  FIG. 4 is a flowchart for explaining the inter-system handover operation when the WiMAX system transits to a standby state. Note that the IP address of the terminal does not change during inter-system handover, and the network connection is maintained.

  The data communication unit 31 determines whether there is no user data transmission / reception for a certain period in the communication state (connected state) of the WiMAX system (step S101), and when there is no user data transmission / reception for a certain period (in the case of Yes) Then, transition to a standby state (idle state or sleep state) by the WiMAX system is initiated by the terminal or the base station (step S102).

  After transitioning to the standby state, the application determination unit 34 determines the type of application currently used, and determines whether or not the application periodically communicates in a short cycle (for example, 128 sec or less). If it is determined (step S103) and communication is periodically performed in a short cycle (in the case of Yes), the communication is terminated, and communication is not performed periodically in a short cycle (in the case of No). The data communication unit 31 refers to the standby state handover (HO) timer value stored in the application-specific handover timer storage unit 51 to determine the handover timer value of the currently used application as a timer (not shown). ) And maintain the standby state by the WiMAX system for the set period, and data communication during that period Determines whether the generated (step S104).

  If data communication occurs during that period (in the case of Yes), the WiMAX communication unit 36 makes a transition to a communication state (connected state) by the WiMAX system (step S107), and if there is no data communication (No In the case), the handover determination unit 33 refers to the reception sensitivity threshold stored in the handover reception sensitivity threshold storage unit 52, and determines whether or not the radio field intensity of the EVDO system is equal to or greater than the threshold (step S105). If it is equal to or greater than the threshold value, the handover execution unit 32 performs control so that the system is handed over to the EVDO system and a standby state (idle state) is established by the EVDO system (step S106).

  FIG. 5 is a flowchart for explaining the inter-system handover operation when the EVDO system transits to the communication state. Note that the IP address of the terminal does not change during inter-system handover, and the network connection is maintained.

  After system handover from the WiMAX system to the EVDO system, the data communication unit 31 determines whether or not user data transmission has occurred in the standby state (idle state) of the EVDO system (step S201), and transmits the user data. If the message does not occur (in the case of No), the EVDO communication unit 35 determines whether or not there is an incoming call from the base station (step S202), and the transmission of user data occurs in step S201 (in the case of Yes). Alternatively, when the communication state is restored by the incoming call from the base station in Step S202 (in the case of Yes), the EVDO communication unit 35 makes a transition to the communication state (connected state) by the EVDO system (Step S203).

  After the transition to the communication state by the EVDO system, the data communication unit 31 refers to the communication state handover (HO) timer value stored in the application-specific handover timer storage unit 51 to determine the application currently used. A handover timer value is set in a timer (not shown), and it is determined whether there is no data transmission / reception for a certain period (eg, 3 sec) during the set period (step S204).

  If there is no transmission / reception of data for a certain period during that period (in the case of Yes), the EVDO communication unit 35 makes a transition to the standby state (idle state) by the EVDO system (step S207), and communication is performed even if the period is exceeded. When the state is maintained (in the case of No), the handover determination unit 33 refers to the reception sensitivity threshold stored in the handover reception sensitivity threshold storage unit 52 and the radio field intensity of the WiMAX system is equal to or greater than the threshold. (Step S205), if it is equal to or greater than the threshold value, the handover execution unit 32 performs control so that the system is handed over to the WiMAX system to enter a communication state (connected state) by the WiMAX system (Step S206).

FIG. 6 is a diagram illustrating an example of a standby state handover (HO) timer value and a communication state handover (HO) timer value for each application type stored in the application-specific handover timer storage unit. is there.
When the application is a browser, the standby state handover timer value is 30 seconds and the communication state handover timer value is 30 seconds. When the application is FTP, the standby state handover timer value is 5 seconds and the communication state handover timer value is 10 When the application is streaming, the standby state handover timer value is 5 seconds and the communication state handover timer value is 5 seconds.

  As described above, when using the WiMAX system, the wireless communication terminal of the present invention performs system handover to an EVDO system that consumes less power than the WiMAX system when the WiMAX system transitions to the standby state. Power consumption can be reduced.

  In addition, when the wireless communication terminal of the present invention performs system handover to the EVDO system and then performs communication for a predetermined time in the EVDO system, the system handover is performed to the WiMAX system having a high communication speed. Can be reduced.

  In addition, system handover is performed after a predetermined time has elapsed, and furthermore, system handover is performed when the radio wave strength of the communication system of the handover destination is greater than a certain value. As a result, wasteful power consumption for handover can be reduced.

In this embodiment, incoming calls of the WiMAX system can be notified via the EVDO system. Therefore, the incoming call of the WiMAX system can be received even if the EVDO system is handed over in the standby state.
In addition, the systems are not limited to the embodiments as long as there is a difference in power consumption in the standby state. For example, the wireless communication systems such as LTE (Long Term Evolution) and UMB (Ultra Mobile Broadband) can be supported. Note that there are.

DESCRIPTION OF SYMBOLS 10 EVDO RF part 20 WiMAX RF part 30 System control part 31 Data communication part 32 Handover execution part 33 Handover determination part 34 Application determination part 35 EVDO communication part 36 WiMAX communication part 40 Display part 50 System storage part 51 Handover timer storage part according to application 52 Handover Reception Sensitivity Threshold Storage Unit 60 Key Input Unit 100 Wireless Communication Terminal

Claims (7)

A first wireless communication system that needs to periodically perform reception processing for incoming call monitoring and transmission processing for maintaining the network connection in a state where the wireless line is suspended while maintaining the network connection; A wireless communication terminal capable of supporting a second wireless communication system that does not need to perform transmission processing for maintaining the network connection in a state where the wireless line is suspended while maintaining
When the wireless communication terminal uses the first wireless communication system, the first wireless communication system transitions to a state in which the wireless communication line is suspended while maintaining the network connection. A wireless communication terminal comprising: a control unit that performs control so that a system handover is performed from the wireless communication system to the second wireless communication system.   The control unit transitions to a state in which the first wireless communication system is in a state where a wireless line is suspended while maintaining network connection, and after the first predetermined time has elapsed, the first wireless communication system performs the second wireless communication from the first wireless communication system. The wireless communication terminal according to claim 1, wherein control is performed so that a system handover is performed to the system.   The wireless communication terminal according to claim 2, wherein the first predetermined time depends on an execution application.   The control unit performs control so that a system handover is performed from the first radio communication system to the second radio communication system when radio field intensity of the second radio communication system is equal to or greater than a threshold value. 4. The wireless communication terminal according to any one of items 1 to 3.   After the system handover from the first radio communication system to the second radio communication system, and after performing a second predetermined time communication in the second radio communication system, the control unit from the second radio communication system The radio communication terminal according to any one of claims 1 to 4, wherein control is performed so that a system handover is performed to the first radio communication system.   The wireless communication terminal according to claim 5, wherein the second predetermined time depends on an execution application.   The control unit performs control so that a system handover is performed from the second radio communication system to the first radio communication system when radio field intensity of the first radio communication system is equal to or greater than a threshold value. Or the radio | wireless communication terminal of 6.

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