Roaming control system for digital mobile telephone set

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a roaming control method for a digital mobile phone, and more particularly to a roaming control method for a digital mobile phone that improves the efficiency of highly efficient roaming control.

【0002】

[Conventional technology]

The roaming control method for mobile phones of digital car phone systems is defined by the digital car phone system standard (STD-27C) produced by the Radio System Development Center (RCR). Since this STD-27C attaches great importance to standby on the home network, when the home network and roaming destination network use the same frequency band together and the mobile phone is in the service area of the roaming destination network. The powered-on mobile phone scans the home network for perches and creates a perch channel table.

【0003】

The mobile phone activates (synchronizes) in order from the perch channel at the top of the perch channel table (arranged in order of strong radio wave) and receives the broadcast information. Since the mobile phone is currently in the service area of the roaming destination network, the network number information of the received notification information includes the roaming destination network ID. In this case, since the network number of the broadcast information is different from the network number of the home network, the mobile telephone determines that it cannot stand by even though it is originally a standby network number, and activates the next perch channel. However, in the area where the mobile phone is located, the home network operator does not provide the service, so it cannot stand by on all the perch channels that can be received. When the mobile phone determines that it cannot stand by on the home network, it then performs a perch scan of the roaming destination network and creates a perch channel table in order to stand by on the roaming destination network. The perch channel table thus created is often the same as the table obtained during the perch scan of the home network. Next, the mobile telephone activates the perch channel at the top of the perch channel table and receives the broadcast information. Since the network number included in the received notification information matches the network number of the roaming destination network, the mobile phone determines that it is a standby channel, activates the standby channel, and transitions to the standby operation.

【0004】

[Problems to be Solved by the Invention]

As described above, in the conventional roaming control method of a digital mobile phone, it is necessary to perform the same perch scan twice before the mobile phone transitions to the standby state, and it is also necessary to activate a useless channel. ..

【0005】

Therefore, an object of the present invention is to provide a roaming control method for a digital mobile telephone capable of transitioning to a standby state in the shortest time even when different carriers (business operators) perform services in the same frequency band. is there.

【0006】

[Means for solving problems]

In order to solve the above-mentioned problems, the roaming control method of the digital mobile telephone according to the present invention is the standby control method of the digital mobile telephone that can stand by between the home network and the roaming network, and the received radio wave is applied to a perch channel having a predetermined level or higher. It starts up to receive the notification information, determines that the network number included in the received notification information matches the home network number, and if they do not match, it matches the roaming destination network number registered in advance in the mobile phone. Mae tree It is configured to determine a match with the net number included in the received broadcast information, and if it matches, wait on the perch channel.

【0007】

Here, the activation of the perch channel whose received radio wave in the previous term is at a predetermined level or higher is performed in descending order of the received radio wave strength.

【0008】

BEST MODE FOR CARRYING OUT THE INVENTION

Next, an example of the embodiment of the present invention will be described with reference to the drawings.

【0009】

FIG. 1 is a schematic block diagram of a mobile telephone showing an example of an embodiment of a roaming control method for a digital mobile telephone according to the present invention.

【0010】

The radio wave signal received via the antenna 1 is converted into an RF signal by the RF unit (RFU) 2 and sent to the baseband unit (BBU) 3, where a predetermined digital signal processing is performed. The output signal from the baseband unit 3 is sent to the control CPU 4, and the roaming control operation and protocol control of the present embodiment described later are performed according to the program procedure stored in the flash memory 5. RAM6 is a memory as a work area for executing the above-mentioned roaming control program. The EEPROM 7 includes a roaming mode management register in which various information for roaming control is stored. The panel CPU 8 notifies the control CPU 4 of an instruction input from the user via the operation of the keyboard 10. For example, the panel CPU 8 notifies the control CPU 4 of a roaming mode switching instruction. The display 9 shows the above-mentioned operation information, the operating state of the device, and the like.

【0011】

In RCR STD-27, which defines the roaming control method of the conventional digital mobile phone, the network number priority type is the basis, but in this embodiment, high-speed roaming is possible because the network number parallel determination is possible. It will be possible.

【0012】

In addition, the perch scan control flag makes the perch scan independent of the network number management, so even if different carriers coexist in the same frequency band, only one perch scan is required.

【0013】

Now, to explain the operation of the present embodiment more specifically, the power-on mobile telephone performs a home network perch scan. After the perch scan is completed, a perch table is created for the perch channels above the cutoff level in descending order of received signal strength. The mobile phone activates (synchronizes) the first channel of the perch table and receives the broadcast information. Then, it is inspected whether the network number included in the notification information and the home network number match. Here, if the network numbers do not match, the mobile telephone checks whether the roaming destination network number and the network number of the received notification information match. In this case, since the network number included in the broadcast information matches the network number of the roaming destination network, the mobile telephone determines that it is a perch channel that can stand by, activates the standby channel, and transitions to the standby state.

【0014】

In the past, perch scans and net numbers were always managed in a one-to-one relationship, so even if the perch channel table of the home network and roaming destination network is the same, the home network and roaming destination network are managed separately. However, in the embodiment of the present invention, the perch scan and the net number are managed independently. That is, a perch scan is performed, and after the channel is activated, it is inspected at once whether all the network numbers registered in the ID information of the standby mobile phone such as the home network and the roaming destination network are matched. This independent management can completely eliminate unnecessary operations.

【0015】

The operation procedure of the present embodiment will be described with reference to FIG. After the power is turned on, it is initialized (step S1), the current roaming mode is set in the roaming mode register (step S2), and the corresponding roaming mode management register (pulled out from the roaming register and has 0 to 7 modes) is read out. , Determine the roaming operation method (step S3). Here, the roaming mode register is a register in which the values of roaming modes 0 to 7 defined by RCR are entered. Next, it is determined whether the current perch measurement location is valid (step S4), and if it is valid, the quality measurement register is initialized (step S5), and when the perch scan method is determined, the perch including the perch channel information is included. Initialize the channel measurement management register (step S6). Subsequently, it is determined whether or not the perch is being measured (step S7), and when the measurement is completed, the perch table is created and the perch selection operation (step S8) is reached.

【0016】

If it is determined in step S4 that the current perch measurement location is not valid, it is determined whether the current perch measurement location is a roaming destination network or a home network (step S9), and it is determined to be a roaming destination network. When this is done, out-of-service processing is executed (step S10), and when it is determined that the home network is used, the current perch measurement location is updated (roaming destination operator) (step S11), and the process returns to step S4.

【0017】

The processing procedure of the perch selection operation will be described with reference to the flowchart of FIG. Enter the perch scan operation and determine if the perch scan control flag is valid, that is, if it is a valid perch measurement location (step S21), if not valid (if invalid), perch scan It is determined whether or not the group instruction pointer indicates the end (step S22), and if it is instructed, the process returns to the process of step S9 in FIG. 2, and if the end is not instructed, the perch scan group instruction pointer is used. Update (step S23) and return to the process of step S21. Here, 10 perch groups form a perch area, and there are 10 perch groups in the home net perch area, and the perch scan group instruction pointer indicates each group.

【0018】

When it is determined in step S21 that the perch scan control flag is valid, the number of activations is checked (step S24), and when the number of activations (for example, 7 times) exceeds a predetermined number, the process of step S22 is performed. If it does not exceed, the perch group is checked (step S25), and if it is OK, it is determined whether or not it has been registered in the error table (step S26). Here, if it is not registered, the received signal strength (RSSI level) is checked (step S27), and if that level is below the cutoff level, the process returns to step S22, and when the cutoff level is exceeded, the channel Execute the startup operation (step S28).

【0019】

In steps S25 and S26, if the result of the perch group check is NG or registered in the error table, the perch channel pointer is updated (step S29) and the perch channel pointer is confirmed (step S30). .. Here, if the perch channel pointer is smaller than the maximum value, the process returns to step S25, and if the perch channel pointer is greater than or equal to the maximum value, the process returns to step S22.

【0020】

Next, the channel activation process will be described with reference to FIG. It waits for the channel to start (step S31), executes the perch selection operation when the start is poor (step S32), and when it starts, receives the notification information and confirms the contents of the notification information (step S33). Here, if it is abnormal, the process proceeds to the process step S35 for selecting the perch.

【0021】

In step S33, when it is determined that the content of the notification information is normal, the reception level of the own station slot is measured in step S34 to check the reception level (step S35), and when it is below the standby permission level, step S The process shifts to the perch selection process of S32, and when the standby permission level or higher is reached, the current roaming destination is initialized to the home network (step S36). Next, it is determined whether or not the received network number matches the roaming destination network number (step S37), and if it does not match, the current roaming destination is confirmed (step S38), and the current roaming destination is If it is a home network, the current roaming destination is set to the roaming destination network (step S39), and the process returns to step S37.

【0022】

If it is determined in step S37 that the received network number matches the network number of the roaming destination, it is determined whether or not the current roaming destination is permitted to roam (step S40), and it is not permitted. If it is prohibited, and if the current roaming destination is the roaming destination network in step S38, the process proceeds to the perch selection process (step S41). In step S40, if the current roaming destination is allowed to roam, the operation shifts to the standby operation.

【0023】

[Effect of the invention]

As described above, according to the roaming control method of the digital mobile phone of the present invention, the response at the time of standby transition and out-of-service transition of the mobile phone is improved, and the standby time in actual operation for smooth standby channel selection is improved. Is shortened, and the program size does not need to be created for each roaming mode, and can be unified and reduced.

[Simple explanation of drawings]

[Figure 1]

It is a block diagram which shows one Embodiment example of the roaming control system of the digital mobile telephone by this invention.

[Figure 2]

It is a flowchart for demonstrating the operation procedure of this Embodiment example.

[Fig. 3]

It is a flowchart which shows the processing procedure of the perch selection operation in this Embodiment example.

[Fig. 4]

It is a flowchart which shows the channel activation processing procedure in this Embodiment example.

[Explanation of symbols]

1 antenna 2 RF unit 3 baseband unit 4 Control CPU 5 Flash memory 6 RAM 7 EEPROM 8 panel CPU 9 display 10 keyboard