JP4537925B2 - Wireless communication terminal and wireless communication method - Google Patents

Description

  The present invention relates to a wireless communication terminal and a wireless communication method.

  Conventionally, as a method of suppressing power consumption during a location registration operation in a wireless communication terminal that performs wireless communication with a base station using any one of a plurality of communication systems, for example, each communication system in a predetermined order A method is adopted in which the acquisition process is performed, and if acquisition of all communication systems is not successful within a certain time, the process shifts to the sleep state, returns from the sleep state at a predetermined interval, and tries the acquisition process again. If the captured communication system is in an overreach state, the communication system is regarded as a capture failure, and the capture process is performed again in the same manner as described above.

Here, for example, in the case of a CDMA2000 1x (Code division Multiple Access 2000 1x) system, there are two communication systems, a first communication system using a 2 GHz band and a second communication system using an 800 MHz band. Each of the communication system and the second communication system has two carrier frequencies to be searched. The wireless communication terminal searches for a signal transmitted from the base station, performs registration processing if one of the signals including the carrier frequency of the first communication system is successfully acquired, and performs registration in the first communication system. Transition to the standby state. In addition, when a signal including the carrier frequency included in the first communication system cannot be acquired, an attempt is made to acquire a signal including the carrier frequency included in the second communication system. To enter standby mode.
Thus, acquisition of the communication system means acquisition of a signal including the carrier frequency of the communication system.

Note that overreach means that a radio communication terminal receives radio waves from a base station located in another cell far away. When the wireless communication terminal is in the overreach state, it is not the base station in the cell where it is currently located, but performs wireless communication with a base station that exists in another cell far away as described above. A large power signal is transmitted to the base station, and power consumption during the location registration operation increases (see, for example, Patent Document 1 below).
JP 2002-44006 A

 By the way, even if the overreach state occurs as described above, for example, when there are few communication systems to be captured, even if the location registration operation is performed in the overreach state, the power consumption is not greatly affected. However, when there are many communication systems to be acquired, such as a tri-band compatible wireless communication terminal, or when there are many carrier frequencies of one communication system, if there is a communication system acquired in an overreach state, the communication is repeated many times. There is a problem in that the power consumption during the position registration operation is increased by performing the capturing operation. The present inventor considers that in the future, as the number of wireless communication terminals compatible with a plurality of communication systems increases, a request for a technique for reducing the power consumption during the location registration operation as described above will increase, and the present invention is filed. To do.

 The present invention has been made in view of the above-described circumstances, and an object of the present invention is to reduce power consumption during a location registration operation in a wireless communication terminal that performs wireless communication using one of a plurality of communication systems. And

 In order to achieve the above object, according to the present invention, as a first solution means for a radio communication terminal, a radio communication terminal that selects one of a plurality of communication systems and performs radio communication with a base station is provided. A system acquisition unit that sequentially performs acquisition processing of each communication system in a predetermined acquisition order and detects the acquisition state of each communication system, and transmits a registration request in the communication system that has succeeded in acquisition, and returns a response to the registration request. A registration processing unit that performs registration processing by obtaining, and a capture order setting unit that sets a priority to the capture order according to the capture state of each communication system and the registration process state. Lowering the priority of the communication system in an overreach state in which acquisition was successful but no response to the registration request was obtained, and setting the lowest priority to the communication system that failed to acquire Together, and performs update processing of the priority each time the system acquisition unit detects the acquisition process and the acquisition status of each communication system.

 Further, in the present invention, as a second solving means relating to the wireless communication terminal, in the first solving means, the system capturing unit performs a capturing process of each communication system with a capturing order according to the priority. It is characterized by being performed only once.

 Further, in the present invention, as a third solving means relating to a wireless communication terminal, in the second solving means, the system capturing unit captures each communication system with a capturing order according to the predetermined number of priorities. When the registration process cannot be performed even after the process is performed, the process shifts to a sleep state for a predetermined time.

Further, in the present invention, as a fourth solving means relating to the wireless communication terminal, in the third solving means, the system capturing unit has a priority set after returning from the sleep state and before entering the sleep state. The acquisition processing of each communication system is sequentially performed in accordance with the acquisition order according to the above, and when there is a communication system in the overreach state, the sleep state is shifted again.

  Further, in the present invention, as a fifth solving means relating to the wireless communication terminal, in the third or fourth solving means, the system capturing unit is configured to prioritize before returning to the sleep state after returning from the sleep state. If there is a communication system that fails in acquisition, the acquisition process for each communication system that has failed to acquire is performed. It is characterized by.

 On the other hand, in the present invention, as a first solving means related to a wireless communication method, a wireless communication method for performing wireless communication with a base station by selecting any one of a plurality of communication systems, in a predetermined acquisition order The first step of performing acquisition processing of each communication system in turn and detecting the acquisition state of each communication system, and sending a registration request in the communication system that has succeeded in acquisition, and obtaining a response to the registration request A second step of performing, and a third step of setting a priority to the capture order according to the capture state of each communication system and the registration processing state, and in the third step, The priority of the communication system in an overreach state in which no response to the registration request was obtained is lowered, the lowest priority is set for the communication system that failed to acquire, and the system Each time the capturing unit performs the capturing process and the capturing state of each communication system, the priority update process is performed.

 Further, in the present invention, as a second solving means related to the wireless communication method, in the first solving means, in the first step, a capturing process of each communication system is performed in a predetermined order according to the priority. It is characterized by being performed only once.

  Further, in the present invention, as a third solving means relating to the wireless communication method, in the second solving means, in the first step, the capturing of each communication system is performed in the capturing order according to the predetermined number of times of the priority. When the registration process cannot be performed even after the process is performed, the process shifts to a sleep state for a predetermined time.

  Further, in the present invention, as a fourth solving means relating to the wireless communication method, in the third solving means, in the first step, after returning from the sleep state, the priority set before the transition to the sleep state is set. The acquisition processing of each communication system is sequentially performed in accordance with the acquisition order according to the above, and when there is a communication system in the overreach state, the sleep state is shifted again.

  Further, in the present invention, as a fifth solving means related to the wireless communication method, in the third or fourth solving means, in the first step, the priority set before returning to the sleep state after returning from the sleep state is set. If there is a communication system that fails in acquisition, the acquisition process for each communication system that has failed to acquire is performed. It is characterized by.

 According to the present invention, it is possible to reduce power consumption during a location registration operation in a wireless communication terminal that performs wireless communication using one of a plurality of communication systems.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a functional configuration of a wireless communication terminal according to an embodiment of the present invention. The radio communication terminal will be described by exemplifying a CDMA2000 1x system compatible mobile phone. As shown in FIG. 1, the wireless communication terminal includes a wireless communication unit 1, a key input unit 2, a display unit 3, an audio output unit 4, a camera unit 5, a control unit 6, and a storage unit 7. The control unit 6 includes a system capturing unit 6a, a registration processing unit 6b, and a capturing order setting unit 6c.

 The wireless communication unit 1 uses one of the two communication systems under the control of the control unit 6, that is, the first communication system using the 2 GHz band in the CDMA2000 1x system and the second communication system using the 800 MHz band. Wireless communication with a base station (not shown). The wireless communication unit 1 performs acquisition processing of each communication system in a predetermined acquisition order during the position registration operation under the control of the system acquisition unit 6a. The key input unit 2 includes dial keys, function keys, power keys, and the like, and outputs operation information of these keys to the control unit 6 as operation signals.

 The display unit 3 is, for example, a liquid crystal display or an organic EL display, and displays various messages, images, and the like based on display signals input from the control unit 6. The sound output unit 4 outputs sound and sound to the outside based on the sound signal input from the control unit 6. The camera unit 5 is a CCD (Charge Coupled Device) camera, for example, and outputs an image signal of a photographed image to the control unit 6 under the control of the control unit 6.

 The control unit 6 controls the overall operation of the wireless communication terminal based on a predetermined control program stored in advance in the storage unit 7, an operation signal input from the key input unit 2, a communication state of the wireless communication unit 1, and the like. To do. The control unit 6 includes a system capturing unit 6a, a registration processing unit 6b, and a capturing order setting unit 6c. The system capturing unit 6a captures data stored in the storage unit 7 during the position registration operation. The wireless communication unit 1 is controlled so that the capturing process of each communication system is performed in the capturing order based on the order table, and the capturing state (whether capturing has succeeded) of each communication system is detected. The registration processing unit 6b performs a location registration process by transmitting a location registration request (registration signal) to the base station in a communication system that has been successfully captured, and obtaining a response (ACK signal) to the location registration request. The acquisition order setting unit 6c stores in the acquisition order table based on the detection result of the acquisition state of each communication system by the system acquisition unit 6a and the registration processing state (whether or not an ACK signal has been received) by the registration processing unit 6b. Update the priority of the capture order set by

 The storage unit 7 is, for example, a flash memory, and stores in advance a control program executed by the control unit 6, and stores an acquisition order table, an image signal input from the camera unit 5, and other data. In the present embodiment, the system capturing unit 6a, the registration processing unit 6b, and the capturing order setting unit 6c are individually described. However, these functions may be integrated as the control unit 6.

 Next, the operation of the wireless communication terminal configured as described above (specifically, the acquisition process of each communication system by the system acquisition unit 6a, the registration processing unit 6b, and the acquisition order setting unit 6c) will be described with reference to the flowchart of FIG. I will explain. The following description explains the acquisition process of each communication system during the location registration operation for the base station.

 First, the system capturing unit 6a sets control variable n = 0 (step S1). Then, the system acquisition unit 6a controls the wireless communication unit 1 to perform the acquisition process of each communication system in accordance with the acquisition order table stored in the storage unit 7 as shown in FIG. 3A (step S2). ). FIG. 3A shows a capture order table in the initial state. In this figure, carrier frequencies A and B indicate the carrier frequencies of the first communication system, and carrier frequencies C and D indicate the carrier frequencies of the second communication system. In the initial state, the priority of the acquisition order of signals including these carrier frequencies is set such that the carrier frequency A is “1” (1 is the highest priority), the carrier frequency B is “2”, and the carrier frequency C is It is assumed that “3” and the carrier frequency are set to “4”. That is, in step S2, a signal transmitted from the base station is searched, and a signal including the carrier frequency A is captured.

 Subsequently, the system acquisition unit 6a detects the acquisition state of the signal including the carrier frequency A (step S3) and determines whether the acquisition is successful (step S4). In this step S4, when “YES”, that is, when the acquisition is successful, the registration processing unit 6b controls the radio communication unit 1 to transmit a registration signal to the location registration process, that is, the base station (step S5).

 Then, the registration processing unit 6b determines whether or not an ACK signal is transmitted from the base station (step S6). If “YES”, that is, if the ACK signal is received, the registration processing unit 6b determines that the location registration is normally completed, The communication system (in this case, the first communication system) having the captured carrier frequency A shifts to a standby state (step S14). On the other hand, if “NO” in step S6, that is, if the ACK signal cannot be received, the registration processing unit 6b determines that the signal including the carrier frequency A that has been successfully acquired is in the overreach state (step S7).

 On the other hand, if “NO” in step S4, that is, if the capture has failed, the process proceeds to step S8. In other words, when the acquisition has failed or when the acquisition has succeeded but is in the overreach state, the acquisition order table is updated by the acquisition order setting unit 6c in step S8. The acquisition order setting unit 6c sets the priority of the carrier frequency that has failed to acquire the lowest priority, and sets the priority of the carrier frequency that has been in the overreach state to be higher than the priority of the carrier frequency that has failed to acquire. Specifically, for example, when acquisition of the carrier frequency A fails, the priority of the carrier frequency A is updated to “4”, which is the lowest, as shown in FIG.

 Then, the system acquisition unit 6a determines whether acquisition processing is completed for each carrier frequency of all communication systems (step S9). If “NO”, the carrier frequency of the next priority is determined according to the acquisition order table. The acquisition process is performed for (in this case, carrier frequency B) (step S10). When the process of step S10 ends, the process returns to step S3.

 In this way, by repeating the processes of steps S2 to S10, the acquisition process is performed for each carrier frequency of all communication systems. More specifically, for example, as described above, when the acquisition for the carrier frequency A fails in the first order, the acquisition processing is performed for the carrier frequency B in the second order, and the acquisition succeeds but is in the overreach state. As shown in FIG. 3C, the priority of the carrier frequency B is updated to “3”, that is, the priority is lowered but the priority is lower than the carrier frequency A.

 Further, when acquisition of the carrier frequency C fails in the third order, the priority of the carrier frequency C is updated to “4” as shown in FIG. That is, since the acquisition has failed, the priority is lowered, but since the priority is originally lower than the carrier frequency A, the carrier frequency C has the lowest priority. Further, when the acquisition of the carrier frequency D is successful in the fourth order but the state is an overreach state, the priority of the carrier frequency D is updated to “2” as shown in FIG. That is, the priority is higher than the carrier frequency that has failed to be acquired, but since the priority is originally lower than the carrier frequency B, the priority of the carrier frequency D is “2”.

 On the other hand, if “YES” in step S9, that is, if acquisition processing is completed for each carrier frequency of all communication systems, the system acquisition unit 6a increments the control variable n (step S11), and the control variable n is a threshold value. It is determined whether it is smaller than “3” (step S12). In this step S12, if “YES”, that is, if the control variable n <threshold value “3”, the system capturing unit 6a returns to the process of step S2, and all the processing is performed based on the capturing order table updated by the capturing order setting unit 6c. The acquisition process is performed again for each carrier frequency of the communication system. On the other hand, if “NO” in step S12, that is, if the control variable n is greater than or equal to the threshold value “3”, the process proceeds to the sleep mode routine (step S13). The threshold value is not limited to “3” and can be changed as appropriate.

 As described above, when the acquisition process is performed again, the acquisition process is preferentially performed for the carrier frequency in the overreach state in accordance with the updated acquisition order table, and the acquisition is performed for the carrier frequency that has failed to be acquired. By deferring processing, the capture rate of each communication system can be improved. That is, when the capturing process is performed again, the possibility of capturing in the overreach state is reduced, and the power consumption during the position registration operation can be reduced.

  In addition, as described above, even if the number of re-acquisition processes specified by the threshold value “3” is exceeded, if there is a communication system that has failed in the overreach state or / and acquisition, the process proceeds to the sleep mode routine described below. Thus, wasteful power consumption can be suppressed.

 FIG. 4 is a flowchart showing the sleep mode routine. In the sleep mode routine, first, the system capturing unit 6a shifts to a sleep state (step S20). At this time, the wireless communication unit 1 may also shift to the sleep state. Then, the system capturing unit 6a determines whether or not the timer in the sleep mode has been counted up (step S21), and maintains “sleep” if “NO”, that is, if the timer has not counted up. On the other hand, if “YES” in step S21, that is, if the timer has counted up, the system acquisition unit 6a performs acquisition processing for each carrier frequency in accordance with the acquisition order table updated last before shifting to the sleep mode routine. (Step S22).

 Subsequently, the system capture unit 6a detects the capture state (step S23) and determines whether the capture is successful (step S24). If “NO” in this step S24, that is, if acquisition fails, it is determined whether or not acquisition processing has been completed for each carrier frequency of all communication systems (step S25). If “NO” in this step S25, the process returns to the step S22, and the acquisition process is performed for the carrier frequency of the next priority according to the acquisition order table. On the other hand, if “YES” in step S25, that is, if acquisition for each carrier frequency of all communication systems fails, there is a high possibility that acquisition will fail even if acquisition processing is performed again. In order to suppress it, it returns to step S20 and shifts to the sleep state. Note that the re-acquisition processing for each carrier frequency of all communication systems may be performed a predetermined number of times before shifting to the sleep state.

 If “YES” in step S24, that is, if acquisition is successful, the registration processing unit 6b controls the wireless communication unit 1 to transmit a registration signal to the location registration process, that is, the base station (step S26). Then, the registration processing unit 6b determines whether or not an ACK signal is transmitted from the base station (step S27). If “YES”, that is, if the ACK signal is received, the registration processing unit 6b determines that the location registration is normally completed, The communication system having the captured carrier frequency shifts to a standby state (step S30). On the other hand, if “NO” in step S27, that is, if the ACK signal cannot be received, the registration processing unit 6b determines that the signal including the carrier frequency that has been successfully acquired is in the overreach state (step S28). Then, the capture rank setting unit 6b updates the capture rank table (step S29), returns to step S20, and shifts to the sleep state.

As described above, in the sleep mode routine, when there is a communication system in the overreach state, it is possible to suppress wasteful power consumption by shifting to the sleep state, and continuously when the acquisition fails. By performing re-acquisition processing for all communication systems, it is possible to improve the acquisition rate of each communication system.
As described above, according to this embodiment, in a wireless communication terminal that performs wireless communication using one of a plurality of communication systems, it is possible to efficiently acquire the communication system by using the acquisition order table. It is possible to reduce power consumption during the location registration operation.

 In the above embodiment, the radio communication terminal corresponding to the CDMA2000 1x system has been described as an example. However, the present invention is not limited to this, and the present invention can be applied to radio communication terminals corresponding to a larger number of communication systems. it can. The present invention is more effective as the number of carrier frequencies to be captured and the number of communication systems increase.

1 is a configuration block diagram of a wireless communication terminal according to an embodiment of the present invention. It is a flowchart which shows operation | movement of the radio | wireless communication terminal in one Embodiment of this invention. It is explanatory drawing which shows the acquisition order table in one Embodiment of this invention. It is a flowchart which shows the sleep mode routine in one Embodiment of this invention.

Explanation of symbols

 DESCRIPTION OF SYMBOLS 1 ... Wireless communication part, 2 ... Key input part, 3 ... Display part, 4 ... Audio | voice output part, 5 ... Camera part, 6 ... Control part, 6a ... System capture part, 6b ... Registration process part, 6c ... Capture order setting Part, 7 ... storage part

Claims (10)

A wireless communication terminal that performs wireless communication with a base station by selecting any one of a plurality of communication systems,
A system acquisition unit that sequentially performs acquisition processing of each communication system in a predetermined acquisition order and detects the acquisition state of each communication system;
A registration processing unit that performs registration processing by transmitting a registration request in a communication system that has succeeded in capturing, and obtaining a response to the registration request;
A capture order setting unit that sets priority to the capture order according to the capture state of each communication system and the registration processing state;
The acquisition order setting unit lowers the priority of a communication system in an overreach state in which acquisition has succeeded but no response to the registration request has been obtained, and sets the lowest priority to a communication system that has failed to acquire. A radio communication terminal characterized in that the priority acquisition process is performed each time the system capturing unit performs a capturing process and a capturing state of each communication system.   The wireless communication terminal according to claim 1, wherein the system acquisition unit performs acquisition processing of each communication system a predetermined number of times in an acquisition order according to the priority.   The system capturing unit shifts to a sleep state for a predetermined time if the registration process cannot be performed even after performing the capturing process of each communication system in the capturing order according to the priority for the predetermined number of times. The wireless communication terminal according to claim 2, wherein:  When the system acquisition unit performs acquisition processing of each communication system in order in accordance with the acquisition order according to the priority set before the transition to the sleep state after returning from the sleep state, and there is a communication system in the overreach state 4. The wireless communication terminal according to claim 3, wherein the wireless communication terminal shifts to a sleep state again.  The system acquisition unit, after returning from the sleep state, performs acquisition processing of each communication system in the order of acquisition according to the priority set before transition to the sleep state, if there is a communication system that failed acquisition, The radio communication terminal according to claim 3 or 4, wherein the radio communication terminal performs an acquisition process on a communication system in a rank next to the communication system in which acquisition has failed. A wireless communication method for performing wireless communication with a base station by selecting any one of a plurality of communication systems,
A first step of performing acquisition processing of each communication system in order in a predetermined acquisition order and detecting the acquisition state of each communication system;
A second step of performing a registration process by transmitting a registration request in a communication system that has been successfully captured and obtaining a response to the registration request;
A third step of setting a priority to the capture order according to the capture state of each communication system and the registration processing state;
In the third step, the priority of the communication system in an overreach state in which acquisition was successful but a response to the registration request was not obtained is lowered, and the lowest priority is set for the communication system in which acquisition failed. A wireless communication method, wherein the priority acquisition process is performed each time the system capturing unit performs capturing processing and capturing state detection of each communication system.  The wireless communication method according to claim 6, wherein in the first step, the capturing process of each communication system is performed a predetermined number of times in the capturing order according to the priority.   In the first step, if the registration process cannot be performed even if the acquisition process of each communication system is performed in the acquisition order according to the priority for the predetermined number of times, the process proceeds to the sleep state for a predetermined time. The wireless communication method according to claim 7, wherein:  In the first step, after recovering from the sleep state, the communication systems are sequentially processed in the acquisition order according to the priority set before the sleep state transition, and there is a communication system in the overreach state. 9. The wireless communication method according to claim 8, wherein the wireless communication method shifts to the sleep state again.   In the first step, after returning from the sleep state, performing the acquisition process of each communication system in order of acquisition order according to the priority set before transition to the sleep state, if there is a communication system that failed to acquire, The radio communication method according to claim 8 or 9, wherein a capture process is performed on a communication system in a rank next to the communication system in which the acquisition has failed.

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