JPS5972825A - Communication system - Google Patents

Abstract

PURPOSE:To decide a communication channel as an idle channel and to use it by transmitting an audible frequency signal at a communication channel where no carrier signal exists and then detecting again the presence or absence of the carrier signal to have no carrier signal through detection. CONSTITUTION:A channel controller 12 is controlled by a controller 4, and a call channel which is initialized at random is set. At the same time a switch 2 leads the output of an antenna 1 to a demodulator 3 to obtain a reception mode. If no carrier is detected by a carrier detector 7, the reception mode is switched to a transmission mode after a prescribed period of time. Then an audible tone generator 11 is controlled to transmit a tone signal. The transmission mode is reset to a reception mode of the corresponding call channel after a second, and the presence or absence is decided for three seconds for a reception carrier. If a carrier exists, the channel is switched to another call channel. If no carrier exists, the corresponding channel is decided idle and stored in an RAM14. Then an automatic switch is carried out to a call channel.

Description

[Detailed Description of the Invention] The present invention relates to communication systems, particularly amateur radio and CB.
(Citizen Band) Pertains to a communication system having a plurality of communication channels such as wireless communication.

A communication device such as amateur radio or American CB radio in the Vl-IF band or UHF band has a system having one real channel and a plurality of communication channels. When making a call, manually search for empty channels, and if an empty channel is found, specify this channel and call the other party from the call channel.
There is a method in which a call is then made using the designated channel.

In this system, manual channel surge makes the operation complicated, makes reliable one-notch operation difficult, and furthermore, there are disadvantages in that one constant channel is likely to be monopolized.

Therefore, an object of the present invention is to provide a communication system that can reliably automatically search for an empty call channel without making the operation complicated.

In the communication system according to the present invention, when making a blank call, it sequentially switches between a plurality of communication channels and detects the presence or absence of a received carrier signal for each channel. After that, the presence or absence of a received carrier signal is detected again, and this communication channel is stored in the memory as an empty channel only when carrier V is not present at this time. Features.

The present invention is characterized in that when the audio frequency signal is received during a call using this communication channel at another station, this is detected and the caller is notified that it is an interruption from another station.

The present invention will be described below with reference to the drawings. .

FIG. 1 is a circuit block diagram of an embodiment of the present invention, in which reception input from a transmitting/receiving antenna 1 is introduced into a demodulator 3 via a transmitting/receiving switch 2. In FIG. This demodulated output is applied to the system controller 4 to drive the speaker 5, and is also applied to the code detector 6 to generate a digital code signal (see Figure 2) sent from the other station (Haku's communication device). Detection takes place.

The system controller 4 variously controls other circuit blocks in accordance with this detection output. In addition, the carrier A7 detector 7
is detected at stage 1, and the presence or absence of an IF (intermediate frequency) carrier in the received signal 8 is detected, and based on this detection signal, the system controllers 1 to [1-ra similarly control other circuit blocks.

On the other hand, the audio input from the microphone 8 is applied to the modulator 9 via the system controller 4, but in this case, the outputs of the code generator 10 and the audible tone signal generator 11 are applied to the modulator 9 as necessary. It will be applied to and modulated. The code generated by the code generator 10 is information (lower side) of the number of bits (upper column) as shown in FIG. 2, and is a digital code signal of 120 pits or more. That is, the start bit consists of 75 pits and serves as information that notifies in advance the transmission of each subsequent digital information. The 32-bit local AT IS (Automat
ic 7 transmitter Identic
The cation S 1onal) code is the call sign data information of the own station, and the type code from 2 pins 1 to 2 indicates the type of the call mode, and is information that distinguishes between simultaneous calling and individual calling. The 32-bit partner station code is call sign data information of the partner station with which a call is desired for individual calling, and the 6-bit S-CH code indicates call channel data. The final 33-bit parity code is digital data for the parity shifter.

The signal from the audible tone generator 11 is e.g.
This monotone sine wave is generated for about 1 second when necessary under the control of the system controller 4.

The output of modulator 9 is transmitted from antenna 1 via switch 2. The control of this switching device 2 is also performed from 1 to 5 to 4. In addition, the channel controller 12
is provided to set the frequency for each channel of the communication device based on the output control data from the controller 4, and has, for example, a PLI ()1: islocked loop) configuration. By making the frequency division ratio of the programmable divider of this P1-1 circuit variable in accordance with the control data from the controller 4,
The oscillation frequency of the internal VCO (voltage controlled oscillator) is controlled. By using this VCo output as a local oscillator signal in the demodulator 3, the control 0-54
It becomes possible to receive the specified channel.

Furthermore, by using this vCO output as a modulation carrier in the modulator 9, it becomes possible to transmit the channel specified by the controller 4 in the same way.

The timer 13 is activated by a trigger signal from the controller 4 to count time, and the clock operation of the controller 4 is performed based on the timer output. Reference numeral 14 denotes a memory, which has a RAM (random access memory) configuration, and stores the communication channel, the ΔTIS code 9 of the communication partner station, etc. 9, ;], I, -15
is ROM (read only memory) V), own station A ■
1゜16, where the S symbol @ etc. is memorized, is PTT (P
ush to Ta1k) It is a switch f, and pressing this switch changes the transmitting state.

Reference numeral 17 denotes a call code setting switch, which allows selection of individual and simultaneous calling modes and setting of the partner station's ATIS sign month. Reference numeral 18 denotes an end switch for notifying the system of the end of communication, and reference numeral 19 an interrupt switch for designating an interrupt to a busy channel.

FIG. 3 (△>, (B) is a flowchart explaining the operation of the embodiment of the present invention, in which the single connectors shown by A are connected to each other in a manner similar to η, and the single connectors shown by Note that C-CLl in the figure is a call channel, and is a single channel that transmits only the code signal shown in FIG. 2 for output to the other station. S
-CH is a speech channel, and indicates a channel for transmitting and receiving speech, codes, and audible tones, and designates one channel 17 out of a plurality of channels.

When the power is turned on, random initial setting is first performed as a communication channel. After that, the call channel is returned and the initial reception is completed. In this standby state, a call is made or a judgment is made as to whether the call has been made or not, and the process proceeds to each operation.

First, the case of calling, that is, calling will be explained. The call code setting switch 17 is manually operated to set the mode and the partner station (only in the individual call mode), and each code is stored in the RAMI4. Next, P.T.
By pressing the T switch 16, an empty call channel search is automatically performed. In addition, this PTT switch 16 has a transmitting switching function during a call, and -
As mentioned above, it is used in conjunction with the empty channel υ~-ji start function, but to distinguish between them, if you press the PTT switch during the call mode, the call mode setting flag will be displayed, and if the call is in progress, this flag will not be activated. The configuration is such that the flag is not output, and the controller 4 determines the presence or absence of this flag and automatically selects the mode.

Automatic selection of empty communication channels is performed in the following procedure. ] The channel controller 12 is controlled by the roller 4 and the randomly initialized communication channel (RAM
14 (previously stored at the time of initial setting), the switch 2 switches the output of the antenna 1 to the demodulator 3.
Once installed, it will operate normally and enter the receiving state. here,
If the gear is detected by the carry 7 detector 7, that channel is a busy (used) channel.
A transition to the next channel occurs. If there is no carrier, the reception state is maintained for another 3 seconds, and if a carrier is detected during that time, the channel is advanced again.

If no carrier is detected during the three seconds, the transmit state is switched and the audible tone generator 11 is controlled.
The I K I-I Z signals are sent out for every second. These, 3
Judgment of the passage of time such as seconds and 1 second is performed by the control of the timer 13, and the judgment of the passage of time for each of the following operations is similarly controlled by the operation control of the timer 13. shall be taken as a thing.

After 1 second has elapsed, the device returns to the reception state of the communication channel and judges whether or not there is a reception signal for 3 seconds. If there is a carrier (21), the channel is switched again to another communication channel, and if there is no carrier (7), this communication channel is determined to be an empty channel and this channel is stored in the RAM 14. This operation is sequentially performed for each of a plurality of communication channels, making it possible to search for an empty channel. 1K for 1 second
The Hz signal is transmitted only if the call channel is busy. This IKHz monotone signal will be received by the user of the channel, and as a result, the receiver who received this monotone signal will be able to open the empty channel by pressing the PTT switch 16 to send out a carrier, as will be described later. Callers in the middle of the day will be notified that the channel is in use, allowing them to be assured of a free channel.

When the empty call channel is searched for and stored in the memory, the call channel is automatically switched to the call channel. Here, it is determined whether or not the =1 channel is in use in the receiving state by detecting the output of the Kireliya detector 6. If it is in use, it waits until the end of use, and when the carrier runs out, it is controlled so that a digital code including the local ATTS code is sent out. This digital code is of the type shown in FIG. 2 and includes the idle call channel, remote station ΔTTS code, call scale classification code, etc. stored in the RAM 14, and also includes the R
It also includes the local ATIS code of OM15. Thereafter, the call channel is switched to a receiving state, and in the case of an individual call, a confirmation operation with the other party's station is started.

In this confirmation operation, the following things are automatically done. That is, in the receiving state, the presence or absence of the detection output of the code detector 7 is checked for one second, and if the ATrS code etc. from the other party is confirmed, it is determined whether the other party's ATIS code and the ΔTTS code stored in the RAMI 4 match. Once the two match, it is possible to shift to a conversation state.

If the other station's A-Is code cannot be received, or if this
If the ATIS code required by No. 2S3 does not match, the communication channel in the memory 14 is erased and the system automatically returns to the initial waiting state.

All of the above operations are shown in the flowchart of FIG. 3(A). Since all of the above operations are performed automatically, the complexity of operability in the co-op is eliminated, and reliability is significantly improved by making it possible to accurately search for idle channels and accurately confirm the other station. It becomes.

The operation in the call state will be explained based on the flowchart shown on the left side of FIG. 3(B). If there is no operation of the PTT switch 16 or detection output from the carrier detector 7 within the past 3 minutes, the controllers 1 to 4 assume that the call has ended, erase the memory 14, and return the system to the first expected state. Bring it back. If the PTT switch is suppressed within 3 minutes, the transmitter enters the transmitting state. When the PTT switch is released, it enters the receiving state. If an audible tone of IK)-1z is received in this state, it means that a tone signal for confirmation when searching for an empty channel at another station is being sent, so insert the PTT switch 16 for a while. :
1- Send Yariya, and notify other stations as third parties that the communication channel is currently in use.
I am trying to eliminate interruptions to this channel.

During a call, an ATrS code is sent every minute, and this is an operation to satisfy the standards required for personal radios. If the call is over, the switch 18 is operated and the system returns to the initial expectant state.

Next, the operation when called will be explained using the flowchart in the center of FIG. 3 (13). In the standby state, that is, in the call channel setting state? When a code is detected by the Y f4 detector 6, the star 1-bit judgment, data code reading, parity I check, call mode judgment, etc. are performed, and the received △TIS code is stored in the ROM 15. ΔT [Compare with S code. If the two match and it is an individual call, the designated call channel is set (13-). If the ΔTTS codes do not match, the system automatically returns to the initial expected reception state.

It is controlled to receive state at the same time as setting to call channel,
The presence or absence of a carrier is detected, and if a carrier is detected here, it is determined that it is a busy channel, and the channel returns to the initial state again. If there is no carrier, an ATIS code or the like is sent out, and after a certain period of time, the communication state is entered.

If the calling mode is simultaneous calling, the call mode is immediately shifted to the designated call channel and the call state is entered. At this time, if a switch for rejecting all calls is provided separately, it is possible to prevent all calls from being answered.

Next, the operation when searching for a busy (in use) channel and making an interrupt call will be described using the flowchart shown in the blank section of FIG. 3(B). When the interrupt command switch 19 is operated, the communication channel becomes a randomly initialized communication channel and is switched to a receiving state. Here, the presence or absence of a carrier is determined based on the detection output of the carrier detector 7, but if there is no carrier, the communication channel is advanced to another 14- and the presence or absence of the carrier A7 is checked again.
A certain channel of ps1a is stored in the memory 14.
After the system is set to this channel, it will start talking. At this time, don't send a message (I need to! 11 to 1
It only monitors the transmission and reception of the 7 channel.

If all channels (J-channel::117) are pressed, the system will automatically return to the initial state.

It should be noted that the numerical examples of the times shown in - are not limited to these, and can be determined as appropriate in consideration of the followable range of the device and various other conditions f1. It takes a certain amount of time to determine the presence or absence of a signal so as not to be sensitive to pulse noise such as ignition noise. For example, if the lock-up time (50 ms) of Pl-1- is taken into consideration, it is possible to set the length to 100 m5. In addition, the system controller 1 to roller 4 in the circuit of FIG.
Of course, the timer 13 and the RAM 14 can be constructed using a so-called micro combi coater.

According to the present invention, the empty channel IL-
Since the check is automatically and reliably performed, there are advantages in that the operation can be carried out in the cylinder and the recognition of the empty tunnel can be ensured. .

[Brief explanation of the drawing]

FIG. 1 (a circuit block diagram of an embodiment of the present invention, FIG. 2 is a transmission data signal including an ATIS code) 71-mat diagram,
FIG. 3 is a flow chart of an embodiment of the present invention. Explanation of codes for important parts 4...System controller 6...Sign detector 7...Carrier detector 12...Channel controller IC15... ...Continued from page 1 of Memory Applicant: Pioneer Co., Ltd. Patent Attorney: Motohiko Fujimura 0 Inventor: Takao Inoue 123-1, Pioneer Co., Ltd. Kawagoe Factory, 25-1 Nishimachi, Yamada, Kawagoe City

Claims (2)

[Claims] (1) A communication system that has a plurality of communication channels, and when searching for an empty communication channel, the plurality of communication channels are sequentially switched, the presence or absence of a received carrier signal is detected for each of these communication channels, and the presence or absence of a received carrier signal is detected for each of these communication channels. Call boot when not present? transmits an audio frequency signal in the channel, detects the presence or absence of a received carrier signal again,
A communication system characterized in that the communication tunnel is stored as an empty channel only when the received carrier signal is absent. (2) The presence or absence of a received carrier signal 8 is detected by sequentially switching a plurality of communication channels, and the presence or absence of a received carrier signal 8 is detected for each of these communication channels, and an audible frequency signal is transmitted in the communication channel when the presence of the received carrier signal 8 is detected. This communication system has an empty channel search method in which the reception carrier signal of the communication channel is set as an empty channel at times, and the audio frequency signal is searched when the audio frequency signal arrives during a call on a predetermined communication channel. 1. A communication method comprising a receiving means for receiving data, and an interrupt is notified by the output of the receiving means.