JPH035697B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a communication system that enables an operator to quickly and comfortably monitor a desired call channel and participate in the call when monitoring the call channel of another station using a personal radio. The present invention relates to a channel monitor device.

Generally, when monitoring the communication channels of other stations using a personal radio, one communication channel is randomly received from among a large number of communication channels by changing the channel scan data, and the selective call data of the receiving channel station is Channel scanning is performed until the selective call data matches the own station's selective call data, and a call operation is started with the call channel station whose selective call data matches. In such a monitor reception operation, conventionally, the first
As shown in the figure, when the monitor switch is turned on and monitor reception begins, the channel signal corresponding to the channel scan data is input to the receiver, and the channel scan continues until the receiver input exceeds the threshold. It is repeated and when the threshold value is exceeded, it is received as a communication channel. The operator listens to the contents of the call from this receiving channel station as audio for a certain period of time (for example, 10 seconds), and channel scanning is repeated until the operator confirms that the person is the intended party. Once this was confirmed, the channel scan data was fixed, and if the selective call data matched, the call operation was enabled. In this way, channel scanning listens to the communication content of randomly selected and received call channels one by one,
Since it is a monitoring method that fixes channel scan data after confirming the communication content of the intended party, it takes time to find the desired call channel, and there are other problems such as having to listen to communication content that is not necessary. There were flaws.
Also, even if you try to increase the channel scanning speed by shortening the listening time of the communication content, it will take at least 10 seconds to judge the communication content by ear.
There was also a limit to increasing the channel scan speed.

The present invention has been made in view of the above-mentioned points, and includes a comparison means for comparing selected call data of a call channel randomly selected and received based on channel scan data with selection data of the own station, and a matching output of the comparison means. mutating means for turning off and on muting of the audio output stage of the receiving section of the personal radio based on the presence or absence of the channel; and channel fixing for fixing the channel scan data to enable voice communication based on the matching output of the comparing means. By providing means, it is possible to quickly and comfortably monitor a target communication channel.

An embodiment of the present invention will be described below with reference to FIGS. 2, 3, 4, and 5.

FIG. 2 shows a receiving section of a personal radio equipped with a transmitting section and a receiving section.
is an antenna. A high frequency amplification circuit 2, a mixing circuit 3, an IF circuit (intermediate frequency amplification circuit) 4, a detection circuit 5, an audio amplification circuit 6, a gate circuit 7, a power amplification circuit 8, and a speaker 9 are sequentially connected to the antenna 1. There is. 10 is a PLL (Phase Lock Loop) circuit as a frequency synthesizer, and this PLL circuit 10 is connected to a microcomputer 11 which will be described later.
is configured to output frequency signals to be applied from the first channel (903.0125MHz) to the 80th channel (904.9875MHz) to the mixing circuit 3 based on the channel scan data from the A predetermined intermediate frequency signal is output from the circuit 3 to the IF circuit 4. A MODEM (modulator/demodulator) 12 as an A/D converter is connected to the output side of the other power of the detection circuit 5.
MODEM 12 is configured to detect and output a control signal included in a received signal from the detected output. The control signal is mainly sent on the first channel as a control channel, and as shown in FIG. (50 bits), a frame synchronization signal (15 bits) that informs the start position of the target data in advance and serves as fixed selective call data, and the target data (172 bits). . The data for this purpose (172 bits), as shown in Figure 4, is a group code (BCD) obtained by converting a 5-digit number as selective call data that is a signal for identifying the other party and whose settings can be changed. 20 bits), a channel code (8 bits) obtained by converting the call channel numbers 2 to 80 into binary, a preliminary command code (4 bits), and a calling name (48 bits).
It consists of a Hagel-Berger code (92 bits) for correcting bit errors in transmitted data. 13 is a monitor switch for starting a monitor operation, and 14 is an own station group code input terminal for inputting the own station's group code. The microcomputer 11 controls a personal radio and is configured as follows. 15
When the monitor switch 13 is turned on, the frame verification circuit 16 as a first comparison means for selective call data, the group code verification circuit 17 as a second comparison means for selective call data, and the auto scan
A control circuit outputs a monitor operation control signal to the PLL data creation circuit 18, and a RAM 19 stores the own station group code inputted from the own station group code input terminal 14 via the control circuit 15.
(random access memory), 20 is a ROM (read only memory) for storing a frame synchronization signal, and 21 is an AND circuit. The frame verification circuit 16 and the group code verification circuit 17 constitute a comparing means 23. The frame verification circuit 16
has the output side of the MODEM 12 and the ROM 20 coupled to its input side, compares the frame synchronization signal included in the reception channel and the frame synchronization signal in the ROM 20, and when the two match, transmits the coincidence signal to the It is configured to output to the input side of the auto-scan PLL data creation circuit 18 and the input side of the AND circuit 21. The AND circuit 21 and the gate circuit 7 constitute a muting means 22. The group code verification circuit 1
7 has the output side of the MODEM 12 and the output side of the RAM 19 connected to its input side, compares the group code included in the receiving channel and the group code in the RAM 19, and determines a match when the two match. It is configured to output a signal to the other input side of the autoscan PLL data creation circuit 18 and the other input side of the AND circuit 21. The auto scan PLL data creation circuit 18 fixes the channel scan data when a matching signal is input from both the frame verification circuit 16 and the group code verification circuit 17.
The PLL circuit 10 is configured to output PLL data for randomly changing channel scan data at other times to the PLL circuit 10. The output side of the AND circuit 21 is coupled to the gate circuit 7, and the gate circuit 7 is configured to be in a conductive state or a non-conductive state depending on the presence or absence of an output from the AND circuit 21.

Next, the operation of the present invention will be explained using the flowchart shown in FIG. In advance, input the same group code as the target communication channel from the own station group code input terminal, and store this in the RAM 19.
Next, when the monitor switch 13 is turned on, a monitor operation control signal is input from the control circuit 15 to the auto scan PLL data creation circuit 18, frame verification circuit 16, and group code verification circuit 17, and the randomly selected channel scan data is is PLL data creation circuit 1 for auto scan
8 to the PLL circuit 10 and enters monitor reception operation. Call channels from 2nd to 80th
When a call channel randomly selected from 79 waves is received, the frame synchronization signal and group code included in this received signal are MODEM.
12 is detected. Next, the frame verification circuit 16 compares this frame synchronization signal with the frame synchronization signal read from the frame synchronization signal ROM 20 in real time. If the comparison result is a mismatch, that is, if there is a mismatch of one or more bits out of the 15 bits that make up the frame synchronization signal, a mismatch signal is sent from the frame verification circuit 16 for auto scan.
The L level signal is output to the PLL data creation circuit 18 and is also input to the AND circuit 21. Therefore, the output side of the AND circuit 21 is at the L level, and the gate circuit 7 is rendered non-conductive, the reception signal of the communication channel is cut off by the gate circuit 7, and no sound is output from the speaker 9. Next, a signal for changing the channel scan data is input to the auto scan PLL data creation circuit 18, and the corresponding channel scan data is output from this circuit 18.
When output to the PLL circuit 10, the next randomly selected communication channel is received. Then,
In the same manner as described above, the frame synchronization signal and the group code are detected, the frame synchronization signals are compared, and when they do not match, an auto scan is performed in which the above operation is repeated. When the frame synchronization signals match, that is, when all 15 bits match, a match signal is output from the frame verification circuit 16 to the autoscan PLL data creation circuit 18, and this autoscan PLL data creation circuit 18 is connected to the group code verification circuit. Wait for signal from 17. At the same time, an H level signal is output from the frame verification circuit 16 to the AND circuit 21. Next, the group code verification circuit 17 compares the group code of the received call channel and the group code of its own station read from the RAM 19 in real time,
If the comparison result is a mismatch, that is, if there is a mismatch of one or more bits among the 20 bits that make up the group code, the mismatch signal is sent to the auto scan PLL.
The data is input to the data creation circuit 18 and auto-scanned. When the group code of the received call channel and the group code set at the local station match, a match signal is output to the auto-scan PLL data creation circuit 18 and an H level signal is output to the AND circuit 21. Therefore, the frequency division ratio data output from the auto-scan PLL data creation circuit 18 to the PLL circuit 10 is fixed, and an H level signal is output from the AND circuit 21 to the gate circuit 7. A conductive state is established, the audio of the target communication channel is output from the speaker 9, and the communication operation becomes possible. Therefore, the operator can switch from the monitoring state to the talking state by pressing the PTT switch (not shown).

The call channel monitoring device according to the present invention includes:
As described above, since the configuration is configured to compare selective call data such as frame synchronization signals and group codes in real time to monitor the target communication channel, it is possible to quickly acquire the target communication partner. can. Furthermore, since a muting means is provided to mute the communication content of a party other than the intended communication party, there is no need to listen to unnecessary communication content, and the monitor operation is comfortable.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing a conventional example, FIG. 2 is a block diagram showing an embodiment of a communication channel monitoring device for a personal radio according to the present invention, FIG. 3 is a block diagram showing the structure of a control signal, and FIG. This figure is a block diagram showing the contents of the data of the control signal shown in FIG. 3, and FIG. 5 is a flowchart explaining the operation of the present invention. 7...Gate circuit, 10...PLL circuit, 12
...MODEM (modulator/demodulator), 16... Frame verification circuit, 17... Group code verification circuit, 18... PLL data creation circuit for auto scan (including channel fixing means), 21... AND circuit, 22
. . . mutating means (consisting of gate circuit 7 and AND circuit 21), 23 . . . comparing means (consisting of frame verification circuit 16 and group code verification circuit 17).

Claims (1)

[Claims] 1. Comprising a transmitter and a receiver, when operating a call channel monitor, a plurality of call channels are randomly received by changing channel scan data, and selective call data of the received channel is In a personal radio device configured to enter a call operation when the data matches selective call data set at the own station, means for comparing the selective call data of the reception channel with the selective call data of the own station; mutating means for turning off and on muting of the audio output stage of the receiving section based on the presence or absence of a matching output; and channel fixing means for fixing the channel scan data based on the matching output of the comparing means to enable a call operation. A call channel monitor device for a personal radio device, characterized in that it is provided with: 2. The communication channel monitoring device for a personal radio according to claim 1, wherein the selective call data to be compared by the comparing means comprises a group code signal whose settings can be changed and a frame synchronization signal which is set in a fixed manner.