JPH069344B2 - Mobile radio communication system standby controller - Google Patents

Description

DETAILED DESCRIPTION [Overview] Regarding a mobile radio communication system such as a cellular system, a plurality of mobile communication service systems are provided for the purpose of improving the possibility of receiving services of a subscription system. A mobile wireless device consisting of a transmitting / receiving device and a standby control device subscribes to at least one system of the above plurality of service systems and can receive the service of the subscription system, while if the service of the subscription system cannot be received, In the mobile radio communication system adapted to receive a service, the standby control device cooperates with the transmission / reception device to scan the control channel of the subscription system or the non-subscription system to determine the control channel of the strongest electric field. Scan means for capturing, and use determining means for determining whether or not the capture control channel can be used Under the predetermined condition, the standby means for putting the transmitter / receiver in the standby state when the acquisition control channel is available and the scanning means are required to scan and acquire the control channel of the joining system in one scan. Scan control means operable to scan and acquire the control channels of the non-subscribed system after repeating for more than a time period.

[Industrial application field]

The present invention relates to a standby control device for a mobile phone,
In particular, a standby control of a mobile phone in a system in which two mobile phone systems are provided in a specific area and two operating companies can provide services, for example, a system such as a cellular system in North America. Regarding the device.

Car phones cannot make calls when cars pass through areas where radio waves do not reach, such as valleys of buildings and mountains. Since such an insensitive area of the radio wave is determined by the position of the station and those areas, the insensitive area differs when the position of the station is changed.
Therefore, as shown in FIG. 5, the cellular system has two systems A, which have different stations and different frequencies for a specific area.
B is provided and the service of either system is received. In the figure, the solid line indicates the service area of system A, and the broken line indicates the service area of system B. In the figure, C _A indicates a dead area in the system A, and C _B indicates a dead area in the system B.
Outside of these dead zones, the services of any system can be received. Systems A and B, for example, as shown in FIG. 6, have available control channels, 21 channels in the illustrated example, and voice channels, 312 channels in the illustrated example, respectively.

A mobile device (telephone) mounted on an automobile joins one of the two systems. The subscribed system is called a Home system, and the non-subscribed system is called a Roam system. Generally, it is cheaper to use the home system service. Therefore, when both the home system and the ROHM system are available, the home system is normally used. When the home system is unavailable, we try to receive the services of ROHM system. However, if mutual service agreements have not been reached between the two operating companies, there may be cases where the non-subscription (ROHM) system service cannot be received.

When the mobile device puts the telephone in a stand-by state, that is, in a state where it can receive service, it first scans the control channel of the joining (home) system, acquires the maximum electric field strength, and determines the available control channel. In other words, in other words, if there is a control channel that can receive radio waves and can transmit / receive necessary data, the channel enters a standby state and the service on the joining (home) system side can be received. On the other hand, if there is no control channel available on the subscription system side, the control channel of the non-subscription (ROHM) system is scanned, and if there is a control channel available, it enters the standby state. The service of the non-subscription system cannot be received during the standby state of the non-subscription system. If an incoming call or call is made from the telephone during this period, the non-subscription system side must receive the service.

The above-mentioned scan for searching the control channel is performed not only when the power of the mobile device is turned on, but also at regular time intervals, for example, every 5 minutes.
In addition, the call is automatically made at the end of the call. As a result, even if the channel with the highest electric field strength becomes another control channel, it is updated every 5 minutes.

[Conventional technology]

FIG. 7 is a flowchart showing a procedure of a mobile station for acquiring a conventional control channel.

First, in step 401, all control channels of the joining system are scanned, the electric field strength thereof is measured, and the strongest control channel is captured. Next, in step 402, it is determined whether or not the control channel acquired is available, and if it is available,
(YES) The process proceeds to step 405 and the control channel enters the standby state.

On the other hand, when the control channel acquired in step 402 is not available (NO), the process proceeds to step 403 to scan all control channels of the non-subscribed system, measure the electric field strength thereof, and acquire the strongest control channel. . Whether or not the captured control channel is usable is determined in step 404, and if it is usable (YES), the process proceeds to step 405 to enter the standby state on the control channel, but when it is not usable (NO), Returning again to step 401, all control channels of the subscribed channels are scanned.

Next, the control procedure of the conventional device in the standby state will be described.

In the standby state, in step 406, it is always determined whether or not there is a "calling" which is an operation of calling another telephone from this mobile device. When it is determined in step 406 that there is a call
If (YES), the calling operation is executed in step 410 to enter the call, and when the call ends, the process returns to step 401 and scans all control channels of the joining system again.

If there is no "call" in step 6, it is determined in step 407 whether or not there is an "incoming call", which is an operation that calls from another telephone. If it is determined in step 407 that there is an incoming call (YES), the incoming call operation is executed in step 411 to enter the call, and when the call ends, the process returns to step 401 and scans all control channels of the joining system again. To execute.

If there is neither an outgoing call nor an incoming call in steps 406 and 407, the process proceeds to step 408, and it is determined whether or not the control channel currently acquired is still available. If the currently acquired control channel is no longer available (NO), step 40
Return to 1 to scan for another control channel of the subscription system, but if available (YES) proceed to step 409. Step 409 is to determine whether or not a predetermined time, for example, 5 minutes, has elapsed since the control channel currently being acquired has been acquired. When the predetermined time has not elapsed (NO)
Returns to step 406 and repeats the procedure described above, but when a predetermined time has passed (YES), returns to step 401 and scans all control channels of the joining system again.

[Problems to be solved by the invention]

However, more than in the conventional car telephone to scan described, for example, a car radio does not reach the area of the fifth subscriber as indicated by C _A in FIG. (Home) system A when subscribing to A system When the mobile station scans the control channel of the subscribing system A during the passage, the control channel of the subscribing system side cannot be captured and the control channel of the non-subscribing (ROHM) system B is captured to The subscription system enters standby mode.

Once the non-subscription system enters the standby state, the above predetermined time has elapsed since the non-subscription system B entered the standby state even if the vehicle subsequently exits the area C _A where the radio waves of the subscription system A do not reach. Until the control system scans the subscription system (Fig. 4, step 40).
1). Therefore, the standby state in the non-subscription system is continued for a predetermined time, and if a call or an incoming call is made during this period, the non-subscription system side, which has a high usage charge, is forced to execute a call.

The above processing is automatically performed by the standby control device,
It is difficult for a car phone user to understand the system problem that the usage fee increases as a result of continuing the call on the non-subscription system side, and the mobile device failure,
Or, they often complain to a car phone operating company that there are too many insensitive areas, which is a problem.

Also, in order to deal with such complaints, if only the subscription system is scanned, the car will move to a region different from the region where the mobile device subscribes, and the subscription system side will take charge of the service in that region. However, if only the non-subscription system side is providing the service, for example, when the mobile station is in the area within the broken line but outside the solid line in FIG. On the side, the control channel cannot be acquired, and a new problem arises that the telephone cannot be called or called.

The present invention has been made in order to solve the problems peculiar to the conventional car telephone system, and the control channel on the non-subscription system side is immediately transmitted even if the radio wave of the subscribing system is temporarily passed. It is an object of the present invention to provide a mobile wireless device such as a car phone that can scan a subscribed channel prior to a scan of a non-subscribed channel without performing a scan.

[Means for solving problems]

FIG. 1 is a principle block diagram of a mobile radio apparatus applied to the mobile radio system of the present invention.

The mobile wireless device of the present invention includes a transceiver device 10 and a standby control device that cooperates with the transceiver device. The transmission / reception device 10 can communicate via an antenna.

In FIG. 1, the standby control device is composed of the following. Reference numeral 1 denotes a scanning means, which cooperates with the transmission / reception device 10 to control a subscription system or a non-subscription system when two car telephone systems exist in a specific area and a mobile station subscribes to one of them. Scan channels and capture control channels. Reference numeral 2 denotes a use determining means, which determines whether or not the control channel captured by the scanning means 1 can be used. Reference numeral 3 denotes a standby unit that puts the transmitter / receiver 10 of the mobile device in a standby state when the captured control channel is available. Reference numeral 4 denotes a scan control means, which controls the scan operation of the scan means 1.

[Work]

When there are two communication service systems in a specific area and a mobile wireless device subscribes to one of them, when the mobile wireless device is set to a communication standby state, under certain conditions,
The control channel of the subscribing system is scanned in preference to the non-subscribing system, and even if the control channel cannot be captured, the scan of the non-subscribing system is not executed within a certain time, but the scan of the subscribing system is executed. After a certain period of time, the non-subscribed system is scanned.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 2 is a block diagram of a standby control device for a car telephone according to an embodiment of the present invention. In the figure, the standby control device is realized by a computer (arithmetic control device) having a CPU (central processing unit) 20 and a memory 30. The CPU 20 includes a scan 1a corresponding to the scan unit 1, a use determining unit 2a corresponding to the use determining unit 2, and a standby unit 3 corresponding to the standby unit 3.
a, a scan control unit 4a corresponding to the scan control unit 4 is provided. Reference numeral 10 is a transmission / reception device.

The transmitter / receiver 10 includes, as a transmitter, a synthesizer 11 for synthesizing a frequency of a channel designated by the CPU 20, and a transmitter 1 for modulating and power-amplifying a transmission signal such as voice or data.
2. There is an antenna sharing unit 13 that transmits a signal from the transmitting unit 12 from the antenna 14. In this circuit, the CPU 20 switches the control channel (FIG. 6) of the subscription system or the non-subscription system while successively applying frequency-designated channel signals to the synthesizer 11. In addition, the transmitter / receiver 10 serves as a receiving side, and the antenna 1
The mixer 15 for mixing the radio wave received at 4 with the signal from the synthesizer 11 and converting it to an intermediate frequency (IF), the detector 16 for detecting the received electric field level from the intermediate frequency, and the signal from the detector 16 are A / D converted. The received electric field signal to the CPU
There are an A / D converter 18 for outputting to 20, a demodulator 17 for demodulating voice and data from the intermediate frequency from the mixer 15, and a data receiving circuit 19 for extracting data from the demodulated signal and outputting the received data to the CPU 20. . Then, the CPU 20 captures the optimum control channel based on the electric field strength output from the A / D converter 18 and the data output from the data receiving circuit 19.

FIG. 3 is a flow chart showing a control procedure performed by the standby control device of FIG. 2 as the first embodiment of the present invention.

In the initial state when the power is turned on, the availability of the joining system is first checked. Therefore, first, the scanning unit 1a
Scans all control channels of the subscribing system in sequence through the transmission / reception device 10 under the control of the scan control unit 4a, measures the electric field strength thereof, and captures the strongest control channel. Next, the use determination unit 2a
It is determined whether the control channel acquired in 302 is usable. If it is available (YES), the process proceeds to step 309, and the standby unit 3a enters the standby state on the control channel of the subscription system. In this standby state, a call can be made.

On the other hand, when the control channel acquired in step 302 is not usable (NO), the process proceeds to step 303 and the scan control unit 4a sets the timer. The set time of this timer is not as long as the conventional 5 minutes and is a relatively short value such as 30 seconds or 1 minute for exiting the dead zone. After the scan control unit 4a sets the timer in step 303, the process proceeds to step 304, in which the scan unit 1a cooperates with the transmission / reception device 10 to scan all the control channels of the joining system again, and measures the electric field strength of the control channel. Capture a strong control channel. Then, in step 305, the use determining unit 2a determines whether or not the captured control channel can be used. If the control channel is available (YES), the process proceeds to step 309 and the standby 3a waits on the control channel of the subscription system. Received.

However, when the channel captured in step 305 is not available (NO), the process proceeds to step 306, and the step 303 is performed first.
At, the scan control unit 4a determines whether the time set by the scan control unit 4a has elapsed (time-out). The timer is automatically updated (for example, counted down) in the computer after being set by the scan controller 4a. When the time has not yet expired, the process returns to step 304, and the operation of scanning all the control channels of the joining system again, measuring the electric field strength thereof, and capturing the strongest control channel is repeated. As a result, as before (Fig. 7, steps 402-403)
If the subscribed system is unavailable, the control channel is scanned in the subscribed system within a fixed time without immediately shifting to the scan of the non-subscribed system.

On the other hand, in step 306, when the timer set in step 303 has timed out (YES), the process proceeds to step 307, where the scanning unit 1a scans all control channels of the non-subscription system and measures the electric field strength thereof. To capture the strongest control channel. Then, in step 308, the use determination unit 2a determines whether or not the captured control channel of the non-subscription system can be used. If the control channel of the non-subscription system is available (YES), the process proceeds to step 309 and the standby unit 3a does not subscribe. Stands by on that control channel of the system. If not available (NO), return to step 304 to scan all control channels of the joining system. If the control channel of the non-subscription system is also unavailable in step 308, the timer is not set in step 303 because the subscription system is not used, and the flow returns to step 304 without setting the timer. After that, the scanning of the joining system and the scanning of the non-joining system are alternately executed (steps 304 to 308).

The control after the standby state, that is, the control after FIG. 3 and the control until returning to are the same as the conventional control from FIG.

As described above, in the standby control device for a car telephone according to the first embodiment, even if it is found that the control channel of the joining system is not in a usable state, the joining system is suspended for a while depending on the timer set in step 303. The control channel of the subscribing system is continuously scanned, thus increasing the possibility of catching the control channel of the subscribing system which is advantageous for receiving the service, that is, the probability of utilizing the subscribing (home) system.

FIG. 4 is a flow chart showing the control procedure of the standby control device of FIG. 2 as the second embodiment of the present invention.

Referring to FIG. 4, the scanning of the control channel and acquisition of the control field with the highest electric field strength (step 301) and the determination of availability of the acquisition control channel (step 302) are performed with reference to FIG. This is similar to the first embodiment described above.

In FIG. 4, if the acquisition control channel for the subscription system is available, the scan control unit 4a does not immediately shift to the standby state as in FIG.
After setting the timer, the standby unit 3a enters the standby state (step 309). That is, once a control channel available in the subscription system is detected, a timer is set.

The set time of this timer is a relatively short value such as 30 seconds or 1 minute as in step 303 of FIG. Further, this timer is not automatically updated after the standby state, but is automatically updated while the scan is being executed.

On the other hand, if there is no control channel in the joining system that can be used in step 302 (NO), the scan control unit 4a checks in step 322 whether the timer of the joining system has expired. If the timer has not expired (NO), the flow returns to step 301 to scan and acquire the control channel of the joining system, and further to determine availability (step 302). That is, once a control channel that can be used by the subscribing system is detected and a standby state is entered, the scanning of the subscribing system is prioritized over the scanning of the non-subscribing system for a certain period of time set by the timer. In this priority scan, the timer is set when it is unusable as shown in FIG. 3 in its substantial processing contents (step 303) until the timer is over (step 3).
06) Similar to scanning a subscription system.

In the case where the timer is over at step 322, the process shifts to the scan of the non-subscription system (step 307) and the availability of the acquisition control channel of the non-subscription system is determined (step 308) as in the case of FIG. . If there is a control channel that can be used for the non-subscription system, the process shifts to step 309 to enter the standby state. If there is no control channel available for the non-subscribed system (step 308, NO), the process returns to step 301 to scan the subscribed system again. Steps 301 and 302 in this case
The repeating operation of (NO), 322 (YES), 307, 308 (NO) is substantially the same as the repeating operation of steps 304, 305 (N), 306 (YES), 307, 308 (NO) in FIG. That is, the control channel acquisition of the subscription system and the control channel acquisition of the non-subscription system are alternately performed. However, as will be described repeatedly, once the control system that has entered the standby state on the available control channel in the subscribing system is set by the timer (step 321 in FIG. 4), the subscribing system waits until the timer expires. The scanning is performed with priority, and once the timer expires, the control channels of the subscribing system and non-subscribing system are controlled until the next control channel of the subscribing system is acquired, even if the non-subscribing system enters the standby state. Scans are repeated alternately. In FIG. 3, the control channel of the subscribing system is preferentially scanned after the system once enters the standby state. In this respect, the control of FIG. 3 and the control of FIG. 4 are different.

In FIG. 4, step 320 is added at the time of initialization after the power is turned on, and the timer is set by the scan control unit 4a to preferentially scan the joining system for a fixed time set by the timer at the time of initialization. Can be made.

The standby control of the mobile radio system associated with the cellular system has been described above, but the present invention can be applied to similar mobile radio systems.

〔The invention's effect〕

As described above, according to the present invention, it is possible to prevent the standby state of the non-subscription system from continuing in the available state of the subscription system, and increase the probability of capturing the control channel of the subscription system. . Therefore, even if the mobile device scans the control channel while the vehicle is passing through the area where the radio wave of the subscription system does not reach, if the vehicle leaves the area where the radio wave of the subscription system does not reach within a certain time, There is an effect that it becomes possible for the subscribing system side to immediately enter the standby state, and eventually the usage fee can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing the principle of a standby control device for a mobile phone according to the present invention, FIG. 2 is a block diagram of an embodiment of a standby control device for a mobile phone according to the present invention, and FIGS. 3 and 4 show the present invention. FIG. 5 is a flow chart showing the operation of the standby control device of the above embodiment, and FIG. 5 is an explanatory view of a system in which there are two car telephone service systems in a specific area and two operating companies can provide services. FIG. 6 is a diagram showing an example of channels used in FIG. 5, and FIG. 7 is a flowchart showing a control operation of a conventional device. (Explanation of Codes) 1 ... Scan Means, 2 ... Use Determining Means, 3 ... Standby Means, 4 ... Scan Control Means, 10 ... Transceiver, 20 ... CPU.

Claims (5)

[Claims] 1. A plurality of mobile communication service systems are provided, and a mobile wireless device comprising a transmission / reception device and a standby control device subscribes to at least one of the plurality of service systems to provide services of the subscription system. On the other hand, in the mobile radio communication system in which the service of the non-subscription system can be received when the service of the subscription system is not received, the standby control device cooperates with the transmission / reception device (10), and Scanning means (1) for scanning the control channel of the subscription system or the non-subscription system and capturing the control channel of the strongest electric field; and a use determining means (2) for determining whether or not the capture control channel can be used, A standby unit (3) for putting the transmitter / receiver in a standby state when the acquisition control channel is available; and the scanning unit, Under the conditions of (1), scan control means for operating to scan and acquire the control channel of the non-subscribed system after repeating the scan and acquisition of the control channel of the subscribed system for a time longer than the time required for one scan. 4) and a mobile radio communication system comprising: 2. The mobile radio communication system according to claim 1, wherein the repeated scanning and acquisition of the control channel of the joining system is limited within a certain period of time. 3. The predetermined condition is that immediately after the start of scanning, or if the control channel is once in a standby state and then is not in a standby state because the control channel becomes unusable. The mobile radio communication system according to claim 2, characterized in that 4. The predetermined condition is that the control channel cannot be used immediately after the start of scanning, when the acquisition control channel of the joining system can be used, and once the control channel is in a standby state. A second aspect of the present invention is characterized in that the standby state is lost due to
The mobile wireless communication system described in the item. 5. The mobile wireless communication system according to claim 3, wherein the fixed time is shorter than a time required for the mobile wireless device to pass through a dead zone of a subscription system.