JPH01252033A - Method for catching control signal - Google Patents

Abstract

PURPOSE:To efficiently catch a control signal by catching the control signal without changing a receiving channel for a constant time and deciding whether the control signal is out of a utilizing range or the temporary degradation of a wave condition. CONSTITUTION:When a power source is applied, CPU 1 detects the receiving channel of the control signal in the first unit of an IDROM 3 according to the program of an ROM 2 and the frequency of the detected receiving channel is set through a synthesizer part 5. Next, the presence and absence of a carrier is detected by a detector 6 to decide whether the frequency to be same as this frequency is set from a control station or not. Then, when the carrier is detected, the synchronous detection of the control signal is executed and a catching condition is decided. At such a time, when the catching condition is satisfied, since it can be considered that the control signal is positioned in the utilizing range of the control station, the control signal is caught and a timer circuit 4 is set. Then, operation is moved to waiting operation such as call processing and reception processing, etc. After that, a time over is investigated and when the time is not over, the recovery of transmission quality is waited. Thus, even in the case of a momentary trouble, the synchronous detection can be executed as soon as the recovery is obtained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to control signal capture for capturing control signals from base stations in mobile radio communications, typified by car telephones and multi-channel access (MCA) systems. It is about the method.

[Conventional technology]

FIG. 4 is a flowchart showing a control signal acquisition method for a service area having a small zone structure as typified by a conventional MCA system. In the figure, ST1 to ST9 indicate each step.

FIG. 5 is a block diagram showing a part of the control circuit of a conventional radio. In the figure, 1 is a central processing unit (CPU).
, 2 indicates the OM in which the program to control the CPU 1 is written, 3 indicates the ID-ROM, and this ID-ROM
3 has 32 groups (units) written therein, and reception channels for control signals used by at least one radio device are written therein.

5 indicates the synthesizer section, and CPU1 is ID-OM3.
is set to the frequency of the receiving channel of the control signal detected from.

6 indicates a carrier detector that detects the carrier of the set reception channel. A indicates an address bus, and D indicates a data bus.

Next, one operation will be explained.

The control signal capture condition is when the received frame synchronization signal is detected for two or more frames in a row, and the system code and switch code match the specified one or more for two or more consecutive frames. The condition for canceling the standby operation is that nine received frames continue or the switch code does not match the specified one for four consecutive frames.

When the power is turned on, the CPU 1 detects the receiving channel of the control # signal of the first unit of the ID-ROM 3 according to the program of the OM2 (step STi), and detects the frequency of the receiving channel detected via the synthesizer lengthizer section 5. is set (step 5T2).

Next, the carrier detector 6 detects whether the same frequency as the frequency of the set reception channel is being transmitted from the control station (base station) or the presence or absence of a carrier (step ST3
).

Next, if a carrier is detected in step ST3, synchronous detection of the control signal is performed, and the aforementioned control signal capture conditions are determined (step ST4).

Next, if the control signal capture condition is satisfied in step 8T4, the control station is located within the usable range of the control station that is sending out the control signal, so the control signal is captured in step ST5.
), enters standby operations such as calling processing and receiving processing (step 5T5).

Next, it is determined whether the condition for canceling the standby operation is satisfied (step 5T7), and if the condition for canceling the standby operation is not satisfied, the process returns to step 8T5.

If the carrier cannot be detected in step 8T3, if the control signal capture condition is not satisfied in step 8T4, or if the standby operation cancellation condition is satisfied in step ST7, the receiving channel is out of service area of the control station.
It is determined whether the unit of the ID-ROM3 is the maximum (step 8T13), and if the unit is not the maximum, the receiving channel of the control signal of the next unit of the ID-ROM3 is detected (step 5T9), and the process returns to step ST2.

However, if it is determined in step ST8 that the unit with ID-OM3 is the largest, the process returns to step ST1.

By capturing control signals in this manner, it is possible to detect available units at the current location.

[Problem to be solved by the invention]

The conventional control signal capture method is performed as described above, so if the transmission quality of the control signal deteriorates significantly due to radio interference, etc., the radio determines that synchronization detection cannot be performed and transmits the signal to the next unit of ID-OM3. In order to detect the reception channel of the control signal, a large number of units are written to ID-ROM 3, and the more units that can be used, the longer it takes to capture the unit before it goes out of synchronization. There was a problem.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a control signal capture method that can capture control signals in a short time.

[Failure to solve the problem]

The control signal capturing method according to the present invention uses a timer circuit to capture the control signal without changing the reception channel for two fixed periods, and detects whether the control signal is out of service area or due to temporary deterioration of the radio wave condition. After determining whether this is the case, the control signal described above or another control signal is captured.

[For production]

The control signal capture method in this invention captures the control signal without changing the receiving channel for a certain period of time, and determines whether the control signal is outside the service area or is due to temporary deterioration of the radio wave condition. capture control signals.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 5Tll to ST22 indicate each step.

FIG. 2 is a block diagram showing a part of a control circuit of a radio device for carrying out the present invention, and the same parts as in FIG. 5 are given the same reference numerals.

In FIG. 2, numeral 4 indicates a timer circuit, which counts the clock signal output from the CPU 1 and outputs a time-over signal to the CPU 1 when the count is up.

Next, the operation will be explained.

When the power is turned on, the CPU 1 detects the receiving channel of the control signal of the first unit of the ID-ROM 3 according to the program of the OM2 (step 5T11), and sets the frequency of the detected receiving channel via the synthesizer section 5. (Step 8T12).

Next, although the same frequency as the frequency of the set reception channel is being transmitted from the control station, the presence or absence of a carrier is detected by the carrier detector 6 (step 5T13).

Next, if a carrier is detected in step 5Ti3, synchronous detection of the control signal is performed, and the above-mentioned control signal capture condition is determined (step 5T14).

Next, if the control signal capture condition is satisfied in step 5Ti4, the control station is located within the service area of the control station that is sending out the control signal, so the control signal must be captured in step 5T.
15), the CPU sets the timer circuit 4 (step 8T16), and enters standby operations such as calling processing and receiving processing (step ST17).

Next, it is determined whether the condition for canceling the standby operation is satisfied (step 5T18), and if the condition for canceling the standby operation is not satisfied, the process returns to step 5T17.

Next, if the condition for canceling the standby operation is satisfied in step 5T18, the timer circuit 4 starts counting the clock supplied from the CPU 1. In step 5T19), the timer circuit 4 starts counting the clock supplied from the CPU 1.
It is determined whether the time limit has exceeded (the control station of the receiving channel being used is out of service range) (step 8T20), and if the time conflict has not exceeded, the process returns to step 5T18 to wait for the transmission quality to be restored.

If the carrier cannot be detected in step 5Ti3 and the control signal capture condition is not satisfied in step 5Ti4, the timer circuit 4 sets the time Φ in step 8T2Q.
If the number of units is exceeded, the control station of the channel being used is out of service range, so it is determined whether the unit of ID-ROM3 is the maximum (step 8T21). If the unit is not the maximum, the next unit of ID-ROM3 is To detect the reception channel of the control signal, step 8T22) returns to step 5T12.

However, if it is determined in step ST21 that the ID-ROM 3 has the largest unit, the process returns to step 5T11.

To capture the control signal in this way, -
Even if there is a momentary radio wave interruption or momentary radio wave disturbance, synchronization detection can be performed as soon as the control signal transmission quality is restored, reducing the time it takes to restore communication, and the more units that can be used, the faster communication will be restored. The time savings will be significant.

FIG. 3 is a flowchart showing another embodiment of the present invention, and in the figure, 5T31 to 8T44 indicate each step.

Next, the operation will be explained. Since steps up to step 5T40 are the same as in the embodiment shown in FIG.
The subsequent steps will be explained.

If the transmission quality of the receiving channel is not recovered in step 5T4Q, the current receiving channel becomes the receiving channel (
(Step ST41).

Next, if it is determined in step 5T41 that the reception channel is substituted, the reception channel of the current unit is detected (step 8T42), and the process returns to step 5T32.

Note that if the carrier cannot be detected in step 8T33, if the control signal capture condition is not satisfied in step 8T34, or if the receiving channel is not acting as a proxy in step 5T41, the control station of the receiving channel being used is out of service range, so the ID - Determine whether the unit of ROM3 is the maximum (Step 8T43), and if the unit is not the maximum - D-Detect the reception channel of the control signal of the next unit of OM3 (Step 5T44), Step 5
Return to T32.

However, if it is determined in step 5T43 that the number of units in the ID-ROM 3 is the maximum, the process returns to step ST31.

In this embodiment as well, the same effects as in the embodiment shown in FIG. 1 can be obtained.

Note that the embodiment shown in FIG. 3 can also be controlled by the control circuit of the radio device shown in FIG. 2.

〔Effect of the invention〕

As described above, according to the present invention, a timer circuit is used to capture a control signal without changing the receiving channel for a certain period of time, and the control signal is detected to be out of service area or due to temporary deterioration of the radio wave condition. After determining whether or not the control signal is present, the control signal described above or other control signal is captured, so that synchronization detection can be performed as soon as the transmission quality of the control signal is restored even if there is a momentary radio wave interruption or momentary radio wave interference. The more units that can be used, the more conspicuously the reduction in the time for returning to communication is possible, and the more efficient the control signal capture becomes.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing a control signal capture method according to an embodiment of the present invention, FIG. 2 is a block diagram showing a part of a control circuit of a radio device according to the invention, and FIG. 3 is a flowchart showing a control signal capturing method according to another embodiment of the invention. FIG. 4 is a flowchart showing a control signal acquisition method, FIG. 4 is a flowchart showing a conventional control signal acquisition method, and FIG. 5 is a block diagram showing a part of a control circuit of a conventional radio device. In the figure, 1 is a central processing unit, and 2 is a ROM. 3 is an ID-ROM, 4 is a timer circuit, 5 is a synthesizer section, 6 is a carrier detector, and 5T11 to 5T22 are steps. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Patent applicant: Mitsubishi Electric Corporation (2 others) ゛ -“ 12 Figure 2 Figure 5

Claims (1)

[Claims] In a control signal capture method for capturing a control signal in mobile radio communication, if the transmission quality of the control signal is significantly degraded, the control signal is captured without changing the reception channel for a certain period of time using a timer circuit of the radio control unit. A control signal capturing method comprising: determining whether the control signal is outside the service area or due to temporary deterioration of radio wave conditions, and then capturing the control signal or another control signal.