JP3869399B2 - Wireless communication device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wireless communication apparatus that selectively uses three or more wireless communication systems.
[0002]
[Prior art]
In recent years, a single user has come to use a plurality of wireless communication systems. Against this background, there has been a demand for a terminal that can use a plurality of communication systems with a single device. Also, a study of handover between different systems, such as from a second generation mobile phone to a third generation, and from a mobile phone to a wireless local area network (LAN) has begun.
[0003]
As systems that consider handover between systems, the second generation mobile communication system GSM (Global System for Mobile communication) used around the world, mainly in Europe, and the third generation system W-CDMA (Wideband-Code Division) Multiple Access). In the dual mode terminal that can use GSM and W-CDMA, hardware and software corresponding to GSM and W-CDMA are independently incorporated. That is, only GSM is assumed as hardware and software used by GSM, and it cannot be switched so that other systems can be used. The same applies to the W-CDMA system. That is, the multimode wireless terminal is realized by connecting optimal hardware for each system (for example, refer to Patent Document 1).
[0004]
Also, several methods are known for inter-system handover using a terminal that switches systems by software (see, for example, Patent Document 2 ). Patent Document 2 discloses a structure of a communication system switching exchange and a switching method when performing inter-system handover based on reception quality.
[0005]
[Patent Document 1]
JP-A-8-237748 (Section 4-5, Fig. 2)
[0006]
[Patent Document 2]
Japanese Patent Laid-Open No. 2002-77965 (FIG. 5).
[0007]
[Problems to be solved by the invention]
Conventionally, handover between wireless communication systems is realized by combining two pieces of hardware that are optimal for each system. However, only handover between two predetermined wireless communication systems can be realized. In order to realize a handover over three or more wireless communication systems, it is necessary to add optimum hardware in accordance with the number of corresponding wireless communication systems, which increases the hardware scale. Note that Patent Document 2 does not disclose the reduction of the hardware scale of the wireless communication device.
[0008]
The present invention has been made in consideration of such circumstances, and the object of the present invention is to provide a wireless communication apparatus that can be realized by simple hardware while enabling handover between three or more wireless communication systems. Is to provide.
[0009]
[Means for Solving the Problems]
To achieve the above object, the present invention provides a communication control program and a communication status monitor corresponding to each of the three or more wireless communication systems in a wireless communication apparatus capable of using three or more wireless communication systems. First storage means for storing a program, second storage means for storing one of the communication control programs or one of the communication status monitoring programs, the second First execution means for executing a program stored in the storage means; third storage means for storing one of the communication control programs or one of the communication status monitoring programs; A second execution means for executing a program stored in the third storage means, one of the second and third storage means as a main storage means, and the other as a sub storage means. And a first load for loading a communication control program corresponding to one radio communication system used among the three or more radio communication systems from the first storage means to the main storage means And a second loading means for loading one of the communication status monitoring programs corresponding to a wireless communication system other than the one wireless communication system from the first storage means to the sub storage means.
[0010]
By taking such a means, communication control using one radio communication system to be used is performed by one of the first and second execution means, and the communication status of radio communication systems other than one radio communication system is controlled. Monitoring can be performed by the other of the first and second execution means. If the wireless communication system used for handover or the like is changed, communication control using the newly used wireless communication system is started by the execution means that has been monitoring the communication status. The first and second execution means correspond to each of the three or more wireless communication systems by appropriately loading the programs stored in the first and second storage means by the first and second loading means. To do. Accordingly, handover between three or more wireless communication systems is realized.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
(First embodiment)
FIG. 1 is a block diagram showing a configuration of a wireless communication apparatus according to the first embodiment. 1 includes a first processor 1, a first memory 2, a peripheral circuit 3, a first bus 4, a second processor 5, a second memory 6, a first wireless unit 7, A first random logic circuit (first logic circuit) 8, a second bus 9, a third processor 10, a third memory 11, a second wireless unit 12, a second random logic circuit (second Logic circuit) 13, third bus 14, first interface (IF) 15, and second interface (IF) 16.
[0013]
The first processor 1 operates based on a program stored in the first memory 2. The first processor 1 collectively controls each unit such as the peripheral circuit 3, the second processor 5, and the third processor, thereby performing processing for performing communication using the four wireless systems as appropriate. The process for executing the application operation is executed. The first memory 2 stores an operation program for the first processor 1. The first memory 2 stores programs for the second processor 5 and the third processor 10 to perform communication using each of the four wireless systems. This program includes a communication control program for realizing communication using each wireless system and a monitor program for monitoring the communication status in each wireless system. The peripheral circuit 3 is a circuit including a key input device, a display device, and the like and a control circuit thereof. The first processor 1, the first memory 2 and the peripheral circuit 3 are connected through a first bus 4.
[0014]
The second processor 5 controls the first radio unit 7 and the first random logic circuit 8 based on the program stored in the second memory 6. The second memory 6 stores an operation program for the second processor 5. The first radio unit 7 transmits and receives radio signals. The first random logic circuit 8 performs digital signal processing of transmission / reception baseband signals. The first radio unit 7 and the first random logic circuit 8 operate as corresponding to one of the four radio systems under the control of the second processor 5. The second processor 5, the second memory 6, the first radio unit 7 and the first random logic circuit 8 are connected through a second bus 9.
[0015]
The third processor 10 controls the second radio unit 12 and the second random logic circuit 13 based on the program stored in the third memory 11. The third memory 11 stores an operation program for the third processor 10. The second radio unit 12 transmits and receives radio signals. The second random logic circuit 13 performs digital signal processing of the transmission / reception baseband signal. The second radio unit 12 and the second random logic circuit 13 correspond to one of the four radio systems under the control of the third processor 10, and the first radio unit 7 and the first random logic circuit 13 It operates independently of the random logic circuit 8. The third processor 10, the third memory 11, the second radio unit 12, and the second random logic circuit 13 are connected through a third bus 14.
[0016]
The interface 15 connects the first bus 4 and the second bus 9. The interface 16 connects the second bus 9 and the third bus 14.
[0017]
Next, the operation of the wireless communication apparatus according to the first embodiment configured as described above will be described.
FIG. 2 is a flowchart of the first processor 1.
When one of the four wireless systems to be used is selected, such as when the user designates a wireless system to be used, the first processor 1 starts the process shown in FIG.
[0018]
In step ST1, the first processor 1 sets one of the second memory 6 and the third memory 11 as a main memory and the other as a sub memory.
[0019]
In step ST2, the first processor 1 reads a program corresponding to a wireless system selected to be used (hereinafter referred to as a selected system) from the first memory 2, and loads this program into the main memory. When the first processor 1 loads the program into the second memory 6 or the third memory 11, the first processor 1 compiles the program stored in the first memory 2 to compile the second memory 6 or the second memory 6. 3 is converted into an executable format.
[0020]
In step ST3, the first processor 10 instructs the processor (hereinafter referred to as the main processor) corresponding to the main memory to execute the program loaded in the main memory.
[0021]
Specifically, for example, the second memory 6 is set as a main memory, and the third memory 11 is set as a sub memory. If the wireless system A is the selected system, the program of the wireless system A is loaded into the second memory 6. Further, the second processor 5 executes the program stored in the second memory 6. Thus, in this specific example, communication using the wireless system A can be performed by the first wireless unit 7 and the first random logic circuit 8.
[0022]
In step ST4, the first processor 1 loads one of the programs of three wireless systems (hereinafter referred to as unselected systems) that are not selected for use into the sub-memory.
[0023]
In step ST5, the first processor 1 instructs the processor (hereinafter referred to as a sub processor) corresponding to the sub memory to execute the monitor program included in the program loaded in the sub memory.
[0024]
In the case of the above specific example, one of the wireless systems B, C, and D that are unselected systems, for example, a program of the wireless system B is loaded into the third memory 11. Then, the third processor 10 executes the communication status monitor program of the wireless system B, so that the communication state related to the wireless system B is monitored by the second wireless unit 12 and the second random logic circuit 13. Note that the communication status is monitored, for example, by measuring received signal strength (RSSI).
[0025]
In step ST6 and step ST7, the first processor 1 waits for the necessity of inter-system handover or the elapse of a certain time after performing step ST4. If the predetermined time has elapsed in this standby state, the first processor 1 returns the process to step ST4. Thus, the first processor 1 loads one of the programs of the unselected system into the sub memory at regular intervals. In step ST4, the first processor 1 sequentially changes the program to be loaded.
[0026]
In the case of the above specific example, the programs of the wireless systems B, C, and D are sequentially loaded into the third memory 11. And the 2nd radio | wireless part 12 and the 2nd random logic circuit 13 are switched to the state which monitors the communication state regarding radio | wireless system B, C, D sequentially.
[0027]
Thus, when the first processor 1 repeats the processes of steps ST4 to ST7, the roles of the second processor 5 and the third processor 10 are as shown in FIG.
[0028]
The main processor executes both the communication control program and the communication status monitor program. Therefore, the communication status related to the selection system is also monitored in the radio unit and the random logic circuit controlled by the main processor. In this way, the communication status of each radio system measured by the first radio unit 7 and the first random logic circuit 8, and the second radio unit 12 and the second random logic circuit 13 is, for example, illustrated in FIG. 4 is stored in the first memory 2 in the state shown in FIG. The monitoring result stored in the first memory 2 is used as information for determining whether or not to perform inter-system handover.
[0029]
If the system handover is necessary, the first processor 1 moves the process from step ST6 to step ST8. In step ST8, the first processor 1 changes the main memory. That is, if the second memory 6 is set as the main memory before that, the third memory 11 is newly set as the main memory, and conversely if the third memory 11 is set as the main memory. For example, the second memory 6 is newly set as the main memory.
[0030]
The wireless system that is the handover destination is one of the previously unselected systems, and when steps ST4 to ST7 are repeated, the programs of the unselected systems are sequentially loaded into the sub-memory. In some cases, the program set for the handover destination radio system is already stored in the memory set as the main memory. Therefore, in step ST9, the first processor 1 confirms whether or not the program of the handover destination radio system is loaded in the new main memory.
[0031]
When step ST9 is NO, the first processor 1 moves the process to step ST10. In Step ST10, the first processor 1 loads the program of the handover destination wireless system from the first memory 2 to the main memory. However, when step ST9 is YES, since loading of such a program is not necessary, the first processor 1 passes step ST9.
[0032]
In step ST11, the first processor 1 instructs the main processor to execute the program loaded in the main memory. Thus, a state is established in which the handover destination wireless system is communicated as the selected system.
[0033]
In step ST12, the first processor 1 confirms whether or not the channel has been established in the handover destination radio system. If the channel can be established, since the handover is completed, the first processor 1 returns the process to step ST4. Thereafter, steps ST4 to ST7 are performed in the same manner as described above, and the roles of the second processor 5 and the third processor 10 are as shown in FIG. That is, by performing the handover, the roles of the second processor 5 and the third processor 10 transition from the state shown in FIG. 3 to the state shown in FIG.
[0034]
If the channel cannot be established in the handover destination wireless system, the handover cannot be performed. In this case, the selection system is a wireless system used before handover is required. Therefore, the first processor 1 shifts the processing from step ST12 to step ST13. In step ST13, the first processor 1 changes the main memory. That is, the main memory is returned to before the handover is required. As a result, the program of the selected system prior to attempting the handover remains stored in the memory that newly becomes the main memory. Therefore, the wireless communication apparatus returns to the state before the handover is required. Thereafter, the first processor 1 returns the process to step ST4.
[0035]
As described above, according to the wireless communication apparatus of the first embodiment, the first processor configured by the second processor 5, the second memory 6, the first wireless unit 7, and the first random logic circuit 8. It has only two systems of communication units: a system and a second system composed of a third processor 10, a third memory 11, a second radio unit 12, and a second random logic circuit 13. However, it is possible to perform communication using the four wireless systems as appropriate. Moreover, handover between these four wireless systems can be performed without interrupting communication.
[0036]
(Second Embodiment)
The configuration of the wireless communication apparatus according to the second embodiment is as shown in FIG. 1 as with the wireless communication apparatus of the first embodiment. The wireless communication apparatus according to the second embodiment differs from the wireless communication apparatus according to the first embodiment in the processing contents of the first processor 1.
[0037]
FIG. 6 is a flowchart of the first processor 1 in the second embodiment. In addition, the same code | symbol is attached | subjected to the process same as FIG. 2, and the detailed description is abbreviate | omitted.
[0038]
As shown in FIG. 6, in the second embodiment, the first processor 1 performs the process of step ST21 instead of step ST4 in the first embodiment, and additionally performs the process of step ST22.
[0039]
In step ST21, the first processor 1 loads one of the monitor programs of the unselected system into the sub memory. That is, in step ST4 in the first embodiment, all the programs related to one of the unselected systems are loaded into the sub memory, whereas in the second embodiment, only the monitor program is loaded into the sub memory. To do.
[0040]
Thus, for unselected systems, the communication control program is not loaded into the sub memory. Therefore, when step ST9 is YES, the first processor 1 shifts the process to step ST23 before step ST11. In step ST23, the first processor 1 additionally loads only the communication control program among the programs of the handover destination radio system from the first memory 2 to the main memory.
[0041]
As described above, in the wireless communication apparatus according to the second embodiment, when the loop of step ST21 and step ST5 to step ST7 is being executed, only the monitor program is loaded into the sub-memory. Therefore, the first processor 1 at this time It is possible to reduce the load of the first embodiment.
[0042]
Each of the above embodiments can be modified in various ways as follows.
In each of the above-described embodiments, for any of the first processor 1, the second processor 5, and the third processor 10, the processing to be performed by the processor can be distributed to a plurality of processors.
[0043]
In each of the embodiments, the program for each wireless system stored in the first memory 2 can be acquired from an external memory card or downloaded by wireless communication.
[0044]
In each of the above-described embodiments, it is possible to limit the wireless system whose communication status is to be monitored to only a part of unselected systems. That is, it is possible to perform operations that do not support all wireless systems according to user needs or according to the circumstances of contracts with telecommunications carriers. Specifically, if only the wireless system A and the wireless system B can be used, the communication state is monitored only for one wireless system that is not the selected system. By doing so, it is possible to efficiently operate as a dual-mode wireless communication device while omitting unnecessary monitoring operations. This is convenient when the user forgets to make a contract with a telecommunications carrier regarding the use of some wireless systems and tries to use only some of the wireless systems.
[0045]
In each of the above embodiments, the communication status of the selection system can be monitored by the sub processor.
[0046]
In each of the above embodiments, the number of available wireless systems may be any number as long as there are three or more.
[0047]
Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.
[0048]
【The invention's effect】
The present invention can be realized with simple hardware while enabling handover between three or more wireless communication systems.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a wireless communication apparatus according to a first embodiment.
FIG. 2 is a flowchart of the first processor 1 in the first embodiment.
FIG. 3 is a diagram showing the roles of a second processor 5 and a third processor 10;
FIG. 4 is a view showing a monitoring result stored in the first memory 2;
FIG. 5 is a diagram showing the roles of the second processor 5 and the third processor 10;
FIG. 6 is a flowchart of the first processor 1 in the second embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... 1st processor, 2 ... 1st memory, 3 ... Peripheral circuit, 4 ... 1st bus | bath, 5 ... 2nd processor, 6 ... 2nd memory, 7 ... 1st radio | wireless part, 8 ... 1st random logic circuit, 9 ... 2nd bus, 10 ... 3rd processor, 11 ... 3rd memory, 12 ... 2nd radio | wireless part, 13 ... 2nd random logic circuit, 14 ... 3rd Bus, 15 ... first interface, 16 ... second interface.

Claims (8)

In a wireless communication apparatus that can use three or more wireless communication systems,
First storage means for storing a communication control program and a communication status monitor program corresponding to each of the three or more wireless communication systems;
A second storage means for storing one of the communication control programs or one of the communication status monitoring programs;
First execution means for executing a program stored in the second storage means;
Third storage means for storing one of the communication control programs or one of the communication status monitoring programs;
Second execution means for executing a program stored in the third storage means;
Means for setting one of the second and third storage means as main storage means and the other as sub storage means;
First loading means for loading a communication control program corresponding to one wireless communication system used among the three or more wireless communication systems from the first storage means to the main storage means;
And a second loading means for loading one of the communication status monitoring programs corresponding to a wireless communication system other than the one wireless communication system from the first storage means to the sub storage means. Wireless communication device. The first loading unit loads a communication control program and a communication status monitoring program corresponding to the one wireless communication system to be used from the first storage unit to the main storage unit. Item 2. The wireless communication device according to Item 1. The second load means loads the communication status monitor program into the sub storage means after a communication channel is established by executing the communication control program loaded into the main storage means. The wireless communication apparatus according to claim 1. 2. The second loading unit loads a plurality of communication status monitoring programs corresponding to wireless communication systems other than the one wireless communication system periodically and sequentially into the sub storage unit. The wireless communication device described. The second loading unit loads the communication control program corresponding to the same wireless communication system as the communication status monitoring program from the first storage unit together with the communication status monitoring program to be loaded into the sub storage unit. Loaded into the sub-storage means;
The system further comprises control means for controlling the execution means for executing the program stored in the sub storage means to execute the communication status monitoring program among the programs stored in the sub storage means. The wireless communication apparatus according to claim 1. The first loading means stores the communication control program corresponding to the new wireless communication system to be newly set in the main storage means when the one wireless communication system is changed. 6. The wireless communication apparatus according to claim 5, wherein if stored in the means, the communication control program is not loaded. 6. The second load means periodically loads a plurality of communication status monitoring programs and a plurality of communication control programs corresponding to wireless communication systems other than the one wireless communication system. A wireless communication device according to 1. First and second transmission / reception circuits for transmitting and receiving radio signals;
First and second signal processing means for performing baseband signal processing accompanying transmission / reception in the first and second transmission / reception circuits;
The first and second execution means execute the communication control program, thereby performing communication using the wireless communication system to which the communication control program corresponds, and the first transmission / reception circuit and the first execution circuit Controlling the signal processing means, or the second transmission / reception circuit and the second signal processing means,
The first and second execution means execute the communication status monitor program to monitor the communication status in the wireless communication system supported by the communication status monitor program. 2. The wireless communication apparatus according to claim 1, wherein the first signal processing unit or the second transmission / reception circuit and the second signal processing unit are controlled.

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