JPH05122134A - Digital cell call repeating system - Google Patents

Abstract

PURPOSE:To shorten an answer back time and to prevent the generation of malfunction due to radio interference by adopting a squelch repeating system as the repeating system of an incoming repeating means in a repeating station and allowing repeating operation only for a fixed time from the reception of an answer back command. CONSTITUTION:When an outgoing repeating means 3 in the repeating station detects an answer back command signal from a master station 1 to a slave station 2, a timer is started only for a fixed time. A repeating control means 7 enables the incoming repeating means 4 only at the time of operating a timer 6. During the period, an answer back signal from the slave station 2 is transmitted to the master station 1 through the repeating station 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relay system at the time of answering back in a digital cell call system, and more particularly to a digital cell call relay system which shortens the answerback time and prevents malfunction due to interference.

In a fixed system digital cell call system such as a municipal disaster prevention administrative radio system, there is a method of controlling relay open / close at a relay station by a digital cell call signal when an answerback is returned from a slave station. Since it takes a long time to return the answer back from the slave station, it is desired that this time can be shortened.

There is also a method in which relay control from a slave station is performed by squelch relay control without using a digital cell call signal, but in this case, it is desired that malfunction of relay due to interference of external radio waves does not occur. ..

[0004]

2. Description of the Related Art FIG. 4 shows a conventional digital cell call relay system, in which a relay operation control (relay open, relay close) of a relay station is also performed by a digital cell call signal. Reference numeral 10 denotes a relay station radio that constitutes a master station provided in a public office or the like. Reference numeral 20 is a public office radio, and 30 is a slave radio, which constitute a relay station. Further, reference numeral 40 is a slave station radio which constitutes the slave station (1), and 50 is a slave station radio which constitutes the slave station (2).
Communication between the relay station radio 10 and the office radio 20, and between the hall radio 20 and the slave radio 40 or 50 is performed by a simplex method.

In the radio station 10 for relay stations, 11 is a transmission signal generator for generating a transmission signal, and 12 is a transmitter (T
X), 13 is a receiver (RX), 14 is a received signal analysis unit for analyzing a received signal, 15 is an antenna, and 16 is a transmission / reception switch for switching the antenna 15 between the transmitter 12 and the receiver 13 for connection. It is a vessel. In the public office radio 20, 21 is a transmitter (TX), 22 is a receiver (RX), 2
3 is an antenna, 24 is a transmission / reception switcher for switching the antenna 23 between the transmitter 21 and the receiver 22, and connecting it. 25 is a reception signal analysis unit for analyzing the reception signal. 26 is a radio device for slave stations for data and press signals. A data and press signal connection unit connected to 30. In the slave station radio 30,
31 is a transmitter (TX), 32 is a receiver (RX), 33 is an antenna, and 34 is an antenna 33, which is a transmitter 31 and a receiver 3.
2 is a transmission / reception switch for switching to and connecting with 2, 35 is a received signal analysis unit for analyzing received signals, and 36 is a data and press signal connection unit for connecting data and press signals to the public office radio 20. In the slave station radio 40, 41 is a transmitter (TX), 42 is a receiver (RX), 43 is an antenna, 44 is a transmission / reception switch for switching the antenna 43 between the transmitter 41 and the receiver 42, and 45. Is a transmission signal generation unit that generates a transmission signal, and 46 is a reception signal analysis unit that analyzes the reception signal. In the slave station radio 50, 51
Is a transmitter (TX), 52 is a receiver (RX), 53 is an antenna, 54 is a transmission / reception switcher for switching the antenna 53 between the transmitter 51 and the receiver 52, and 55 is a transmission signal for generating a transmission signal. The generation unit 56 is a received signal analysis unit that analyzes the received signal.

In the case of the digital cell call system shown in FIG. 4, control of the relay operation of the relay station (relay open, relay close) is also performed by the digital cell call signal. After the master station broadcasts to each slave station via the relay station, when, for example, the response (answer back) of the slave station (1) is obtained by polling, the pre-carrier is transmitted from the relay station radio device 10. After transmitting for 1 second, the wireless device 20 for the public office in the relay station determines the carrier frequency, and becomes the operable state. Next, by transmitting a relay open signal from the master station, the reception signal analyzing section 25 analyzes the relay open signal and the slave station radio 3 via the data and press signal connecting section 26.
Since 0 is set to the transmission state, an answer back command signal is transmitted after 1 second. The slave station (1) that received the call receives this, analyzes it in the received signal analysis unit 46, and receives the command.

FIG. 5 is a time chart showing the return of the answerback signal in the case of the conventional example shown in FIG. 4, where (1) is the transmission from the slave station (1) and (2) is the slave. The transmission from the station (2), (3) shows the reception of the relay station slave station radio, (4) shows the transmission of the relay station master station radio, and (5) shows the reception of the master station. There is. In the figure, PC indicates pre-carrier and AB indicates answer back.

Each slave station sequentially outputs an answerback signal in response to polling by the master station. First, when the slave station (1) sends out the pre-carrier for 1 second, the slave station radio 30 receives this after the squelch response delay time and becomes operable. Next, the slave station (1) sends a relay open signal to the relay station, so that the reception signal analyzing section 35 in the slave station radio 30 analyzes this and sends it to the office via the data and press signal connecting section 36. Since the wireless device 20 is set to the transmission state, the relay operation is started. Next child station (1)
When the pre-carrier is transmitted for 1 second, the master station receives it via the relay station and becomes operable. Next child station (1)
When the desired signal is transmitted as an answerback signal from the transmission signal generation unit 45, the master station receives the data via the relay station, and the reception signal analysis unit 14 analyzes the data to receive the data.

When transmission of the answerback signal from the slave station (1) is completed, the slave station (2) performs the same operation and transmits the answerback signal. The slave station returns the answerback signal by sequentially repeating such a procedure.

FIG. 6 shows another conventional digital cell call relay system, in which uplink relay control is performed by squelch control without using a digital cell call signal. In FIG. 5, the same components as those in FIG.
It lacks a received signal analyzer and data and press signal connections.

In FIG. 6, each slave station sequentially outputs an answerback signal in response to polling by the master station. First, when the slave station (1) sends out the pre-carrier for 1 second, the slave station radio 30 receives this after the squelch response delay time and becomes operable. Next, when the slave station (1) sends the required data from the transmission signal generating section 45 as an answer back signal, the master station receives the data via the relay station,
Data is received by analyzing the received signal analysis unit 14. The same applies to other slave stations.

[0012]

In the conventional example shown in FIG. 4, as shown in the time chart of FIG.
Since the digital cell call signal is used for the relay control when the answerback signal is returned from the slave station, the relay control takes a long time. Therefore, when a large number of slave stations perform answerback, if there is a relay station, there is a problem that the time required to complete the answerback signal return of all the slave stations becomes extremely long.

Further, in the conventional example shown in FIG. 6, the time required for answering back the slave station can be shortened, but in this case, a malfunction of the uplink relay control based on the external radio wave occurs. However, there is a problem that the master station cannot broadcast to the slave station because the station radio 20 is in the pressed state.

The present invention is intended to solve such a problem of the prior art, and in a digital cell call type radio system, it is possible to shorten the time required to return an answerback from a slave station, and It is an object of the present invention to provide a digital cell call relay system which rarely causes a malfunction of relaying due to interference of external radio waves.

[0015]

FIG. 1 shows the basic configuration of the present invention. The present invention relays a signal from the master station 1 to the master station 1 to the master station 1 and a plurality of slave stations 2 to relay the signal from the master station 1 to the slave station 2. In the wireless system of the digital cell call relay system, which includes the relay station 5 having the upstream relay means 4, each slave station 2 returns an answerback signal in response to the answerback command signal from the master station 1, The relay system in the upstream relay means 4 is a squelch relay system, and the timer 6 that operates for a certain period of time after the answer back command signal is received from the master station 1, and the upstream relay means 4 is enabled only when the timer 6 operates. The relay control means 7 is provided in the relay station 5.

Further, in the present invention, in the above digital cell call relay system,
It is characterized in that it is made variable by a timer time setting signal added to the answerback command signal from the master station.

Furthermore, the present invention is characterized in that, in the above digital cell call relay system, the relay system in the upstream relay means 4 is a tone squelch relay system.

[0018]

In the digital cell call relay system of the present invention, the answerback command signal from the master station is also monitored by the relay station, and after receiving this signal, the uplink squelch relay is performed for a fixed time defined by the timer. Allow the operation. If an incoming call is received by the relay station slave station radio within this permitted time, the relay station master station (station) radio station is pressed to receive the answerback signal from the slave station to the master station. Relay to. That is, the answerback signal is transmitted from the slave station after transmitting the precarrier for 2 seconds, and the relay operation control signal (relay open signal) of the relay station by the digital cell call signal is not used.

As described above, in the present invention, when the answerback signal is transmitted from each slave station, the relay operation control signal based on the digital cell call signal is not transmitted.
The time required for answering back signal transmission of each slave station is shortened. In addition, after the answer back command signal is sent, the relay operation is allowed only for a certain time, so if there is an incoming call to the uplink radio of the relay station due to interference, if it is outside this time, the relay operation is Since the station does not relay,
It is possible to prevent a situation in which the master station radio of the relay station is pressed and it becomes impossible to perform downlink broadcasting from the master station. Note that the fixed time in this case does not correspond to the answerback required time for one slave station, but it is necessary to set it as the answerback required time for all the slave stations returned by one answerback command. ..

The relay operation permission time can be changed according to the system configuration (the number of slave stations). In this case, the relay operation permission time can be arbitrarily changed by adding the timer time setting signal to the answerback command signal from the master station.

It is also possible to use the tone squelch relay system as the uplink relay system and to permit the relay operation at the time of answerback signal transmission by tone squelch. This makes it possible to further reduce erroneous control of relay operation due to interference of external radio waves.

[0022]

FIG. 2 shows the configuration of an embodiment of the present invention, in which the same components as those in FIG. 7 are designated by the same reference numerals, and 27 is provided in the public office radio 20 of the relay station. A timer, which is activated by the received signal analysis unit 25.
Reference numeral 28 is a relay whose ON / OFF is controlled by the timer 27.

In the embodiment shown in FIG. 2, when the reception signal analysis unit 25 of the public office radio of the relay station monitoring the signal from the master station detects the answerback command signal from the master station to the slave station. , Start the timer 27. Timer 27
Makes relay 28 during its operation. After that, when there is an incoming call at the receiver 32 of the slave station radio 30, a press signal and a voice line to the transmitter 21 of the public office radio 20 via the relay 28 based on the detection of the radio signal from the slave station. Are connected. Therefore, the answerback signal of each slave station is transmitted to the master station via the relay station.

The timer 27 times out and breaks the relay 28 when the answerback required time of all slave stations has elapsed, so that the connection of the press signal and the voice line to the transmitter 21 of the public office radio 20 is released. It
Therefore, even if there is an incoming call at the receiver of the slave station radio 30 due to interference of an external signal outside the above-mentioned time, the relay 28 disconnects the connection with the transmitter 21 of the station radio 20, The public office radio 20 will not be pressed, and the master station will not be unable to broadcast to the slave stations.

FIG. 3 is a time chart showing the return of the answer back command signal in the case of the embodiment shown in FIG. 2, where (1) is the answer back signal from the master station, and (2)
Is the operation of the relay station timer, (3) is the operation of the relay station relay, (4) is the answer back from the slave station (1), (5)
Is an answer back from the child station (2), (6) is an answer back from the child station N, (7) is interference of interference waves, (8) is an incoming call to the child station radio, and (9) is FIG. The transmission of the master station radio in the case of the conventional example shown in FIG. 4 and (10) show the transmission of the master station radio in the embodiment of FIG.

As shown in FIG. 3, in the case of the conventional example shown in FIG. 6, the transmission state is brought about as shown by A due to the interference of the interfering waves, but in the embodiment of the present invention shown in FIG. In this case, even if there is interference from the interfering wave, it will not enter the transmission state.

In the case of this system, since the relay open signal by the digital cell call system is not used, compared to the system of controlling the relay station to the relay state by the relay open signal like the conventional digital cell call system, the answer back In addition to shortening the time, the relay-enabled time is limited by the timer even when the squelch relay method is used, so that the chance of malfunction of relay control due to interference of external radio waves can be reduced.

In the operation time of the timer 27 in this case, the timer time setting signal is added to the answerback command signal from the master station, and the reception signal analysis unit 25 analyzes the signal and analyzes the timer.
It can be made variable by controlling 7.
In this case, the operating time of the timer 27 can be optimized according to the number of slave stations that make up the wireless system.

In addition, in this case, the activation of the office-directed radio 20 of the relay station by the answerback signal from the slave station may be performed by the squelch relay system by detecting the carrier signal from the slave station as in the above example, or A tone squelch relay system may also be used in which both a carrier signal and a voice signal are detected based on the transmission of a constant tone signal from the slave station. In the case of the tone squelch relay system, by assigning a tone frequency to each slave station in advance, it is possible to further reduce the chance of malfunction of relay control due to interference of external radio waves.

[0030]

As described above, according to the present invention, the time required for answer back can be shortened in the wireless system of the digital cell call system, and the malfunction of the relay control due to the interference of external radio waves can be prevented. Can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a principle configuration of the present invention.

FIG. 2 is a diagram showing a configuration of an exemplary embodiment of the present invention.

3 is a time chart showing return of an answerback signal in the embodiment shown in FIG. 2, where (1) is an answerback signal from a master station, (2) is a timer operation of a relay station, and 3) is the relay operation of the relay station, (4) is the answer back from the child station (1), (5) is the answer back from the child station (2), (6) is the answer back from the child station N, (7) is interference of interfering waves, (8) is an incoming call to a slave station radio, (9) is a transmission from the master station radio in the case of the conventional example shown in FIG. 6, and (10) is a diagram of FIG. 7A and 7B respectively show transmissions of the master station radio in the embodiment.

FIG. 4 is a diagram showing a conventional digital cell call relay system.

5 is a time chart showing the return of an answerback signal in the case of the conventional example shown in FIG. 4, where (1) is transmission from the slave station (1) and (2) is the slave station (2). Send from,
(3) shows reception by the slave station radio of the relay station, (4) shows transmission of the master station radio of the relay station, and (5) shows reception of the master station.

FIG. 6 is a diagram showing another conventional digital cell call relay system.

[Explanation of symbols]

 1 Master station 2 Slave station 3 Downlink relay means 4 Uplink relay means 5 Relay station 6 Timer 7 Relay control means

Claims (3)

[Claims] 1. Downlink relay means (3) for relaying a signal from the master station (1) to the master station (1) and a plurality of slave stations (2) and the slave station (2). A relay station (5) having an upstream relay means (4) for relaying a signal from the master station (1) to the master station (1), and each slave station (2) in response to an answer back command signal from the master station (1). ) Returns an answer back signal in a digital cell call relay system wireless system, the relay system in the upstream relay means (4) in the relay station (5) is a squelch relay system and the answer back from the master station (1) The relay station (5) is provided with a timer (6) which operates for a certain time after receiving the command signal, and a relay control means (7) which enables the upstream relay means (4) only when the timer (6) is operating. Digital cell call relay characterized by method. 2. The digital cell call relay system according to claim 1, wherein the fixed time for which the timer (6) operates is variable by a timer time setting signal added to an answer back command signal from the master station. .. 3. The digital cell call relay system according to claim 1, wherein the relay system in said upstream relay means (4) is a tone squelch relay system.