JPH07110000B2 - Wireless receiver monitoring method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention controls communication by a demand assignment method in which a wireless communication channel is allocated between a slave station and a master station only when a call is originated at the slave station. The present invention relates to a wireless receiver monitoring method for monitoring the occurrence of a failure in an upstream wireless receiver in a multi-directional multiplex communication system.

(Prior Art) As is well known, a multi-directional multiplex communication system has a one-to-N relationship between one master station and a plurality of slave stations that are geographically separated and dispersed around the master station. This is a time division multiplex wireless communication system for performing communication, and one or a plurality of relay stations may be installed depending on the system scale and the like. FIG. 4 shows an example of the configuration of this type of multi-directional multiplex communication system. Among a plurality of slave stations (2 ₁ , 2, ₃ , 2 ₄ , ₂₅ , ..., 2 _n ), the slave stations 2 ₃ and 2 ₄ are the same. Shows an example of a system in which the remaining slave stations 2 ₁ , 2 ₅ , ..., 2 _n are directly wirelessly connected to the master station via the relay station 2 ₂ .

By the way, in a multi-directional multiplex communication system adopting a demand assignment method from the viewpoint of effective use of a wireless communication channel, a slave station stops radio wave transmission except when information is being transmitted to increase the usage time zone of other slave stations. Although there is a slave station that stops the transmission operation, whether or not the uplink receiving station (that is, the master station or the relay station) does not receive it due to the wireless receiving device of its own station It is necessary to monitor whether or not a failure has occurred in the wireless reception device in order to determine that.

Hereinafter, a conventional method of monitoring a wireless receiving device will be described with reference to FIGS.

FIG. 5 shows the configuration of a conventional uplink receiving station (master station / relay station). In FIG. 5, the upper part of the figure shows the wireless transmitter part of the downlink, and the lower part of the figure shows the wireless receiver part of the uplink. In the wireless transmission device part, there is a transmission system composed of the multiplex circuit 11 and the transmitter 13, and a transmission system composed of the multiplex circuit 12 and the transmitter 14, and one system is currently used by the switching operation of the transmission switcher 15. The other system is designed as a backup. Similarly, in the wireless receiver unit, the receiving system is duplicated like the receiver 19 and can be used by switching the receiving switch 21. They are trying to monitor the suitability of this wireless receiver part.

The frame counter 22 generates a timing signal that defines the cycle of the radio frame, and outputs it to the frame pattern generator 23, the polling control circuit 24, and the polling timing generator 26, respectively.

The frame pattern generator 23 generates a control signal defining each time slot in the radio frame based on the timing signal, and outputs it to the multiplexing circuit (11, 12). One polling time slot is set for each radio frame.

The polling control circuit 24, in response to the timing signal, forms a polling signal for calling an arbitrary slave station and soliciting transmission, and outputs it to the multiplexing circuit (11, 12).
This operation is the same for the master station and the relay station, and occurs in response to the timing signal in order, for example, n polling signals (P _{1 to} P _n ).

In the multiplexing circuit (11, 12), one polling signal is arranged in a predetermined time slot in the radio frame together with transmission data and the like. This is wirelessly transmitted via the transmitters (13, 14), the transmission switcher 15, the duplexer 16 and the antenna 17.

Thus, FIG. 7 (a) shows only the polling signals transmitted in consecutive radio frames, but as shown in FIG. 7 (a), it is possible to obtain n from the master station and the relay station. Number of polling signals (P _{1 to} P _n ) are transmitted in sequence,
This is repeated. This repeating cycle is the polling cycle T _P. That is, referring to FIG. 4, the master station 1 is a slave station.
2 ₁ , 2 ₅ to 2 _n , call to the relay station 2 ₂ in order, and the relay station 2 ₂ calls to the slave stations 2 ₃ and 2 ₄ in order. . Slave stations in the subordinate of the relay station 2 ₂ (2 _3, 2 _4, ...) is never directly receives the call from the master station is receive indirectly calls via the RS 2 _2.

On the other hand, in FIG. 6, in the slave station, the polling signal from the master station or the relay station is received by the antenna 28, and the polling pattern detector 34 is transmitted via the duplexer 29 and the receiver 30.
When it is identified that the local station is selected from the master station or the relay station, the polling information generator 35 is activated, and the polling information (station information signal ) Is formed. This is sent from the antenna 28 to the master station or relay station via the multiplex circuit 33, the transmitter 31, and the duplexer 29.

That is, speaking in Figure 4, and transmits the slave station 2 _1, the station information of the same 2 ₅ to the 2 _n is received directly detecting a polling signal immediately own station to the master station. Further, the slave station 2 _3, the 2 ₄ polling signal P ₃ via the RS 2 _2, detects the P _4, as shown in FIG. 7 (b), immediately station information P ₃ of the station ', The same P ₄ ′ is transmitted to the relay station 2 ₂ . Thus to, the uplink of the parent station 1 and relay station 2 _2, without occurring a call to the slave station, always polling period T _P
The station information signal is transmitted from the slave station more than once.

Then, in FIG. 5, in the uplink side wireless reception device portion of the master station or the relay station, the station information signal transmitted from the slave station is received by the antenna 17, and is transmitted to the hybrid 18 and the receiver (19, 20). Be guided. The receiver (19, 20) has a reception electric field detector, and when receiving the station information signal from the slave station, outputs the detected reception electric field signal to the alarm control circuit 25.
On the other hand, the polling timing generator 26, in response to the timing signal from the frame counter 22, the electric field detection timing indicating the time position when the station information signal from the slave station arrives at the uplink side of the master station or relay station. The signal is output to the alarm control circuit 25. As a result, the alarm control circuit
In 25, the received electric field signals of the active system and the standby system from the receivers 19 and 20 are sampled by the electric field detection timing signal,
As a result of sampling, polling cycle from the active system
If the received electric field is not detected for a period of T _P or more, it is determined that the receiver of the working system is faulty, and the reception switch 21 is switched to the standby system. If the received electric field is not detected for a period longer than the polling period T _P from both the active system and the standby system, the fault of the slave station, the fading of the propagation path, the fault of the common part of the reception system (antenna, duplexer, hybrid) Therefore, the reception system is not switched by the reception switcher 21.

(Problems to be Solved by the Invention) However, in the above-described conventional wireless receiver monitoring method, there is a problem that it takes a long time from the occurrence of a failure of the master station receiver to its detection, and lack of swiftness. is there.

For example, as shown in FIG. 7 (c), the slave station 2 ₃ and the 2 ₄ stations information P ₃ 'and the P _4' RS 2 ₂ uplink side reception at time t = t ₁ after receiving Even if a device failure occurs, it can be detected as shown in FIG. 7 (d) at time t = after the reception timing of the station information P ₃ ″ and P ₄ ″ in the next polling cycle.
It is t ₂ , and a delay time (τ ₁ = t ₂ −t ₁ ) longer than the polling period T _P is required from the occurrence of failure to the detection.

Since one slave station is polled in one radio frame, one polling period T _P is a considerably long period depending on the number of slave stations, and switching to the standby system cannot be performed during this period.

It is unfavorable for system operation that the communication between the master station and the slave station is not maintained for a long time, so improvement is desired.

The present invention has been made in view of such conventional problems, and an object thereof is to provide a wireless reception device monitoring method capable of significantly shortening the period from the occurrence of a failure of a master station reception device to its detection. It is in.

(Means for Solving the Problem) In order to achieve the above-mentioned object, the monitoring method of the wireless reception device of the present invention has the following configuration.

That is, the wireless receiving device monitoring method of the present invention is a multi-directional multiplex communication system in which communication control is performed by a demand assignment method in which a wireless communication channel is allocated between a slave station and a master station only when a call originates in the slave station. Is a monitoring method for a wireless reception device that monitors the occurrence of a failure in the upstream wireless reception device; the wireless reception device monitoring method generates a reception electric field detection burst signal to the wireless transmission device of each slave station. Means for transmitting the reception electric field detection burst signal in the reception electric field detection time slot set in each radio frame regardless of whether or not a call has occurred, and radio reception of an uplink receiving station. A device for detecting the received electric field detection burst signal from the received electric field detection time slot; a reception level of the detected received electric field detection burst signal; And a means for judging that there is a failure in the receiving device on the uplink side of the local station when the reception non-detection of the received electric field detection burst signal continues for a period exceeding a predetermined number of radio frames. It is a feature.

(Operation) Next, the operation of the monitoring system of the wireless reception device of the present invention configured as described above will be described.

Each slave station performs a transmission operation at the time position of the reception electric field detection time slot in each radio frame even if no call occurs, and transmits a reception electric field detection burst signal. On the other hand, in the uplink receiving station, that is, the master station or the relay station, the received signal level is monitored at the time position of the received electric field detection time slot, and the reception non-detection of the received electric field detection burst signal continues for a period of several frames, for example. At this time, it is determined that there is a failure in the receiving device on the uplink side of the own station.

Thus, according to the wireless reception device monitoring method of the present invention,
The delay time from the occurrence of a failure to its detection can be set to a plurality of periods of the radio frame.

This period is very short compared to the polling cycle in the conventional method. Therefore, according to the method of the present invention, the period from the occurrence of a failure to its detection can be greatly shortened, and the standby system can be switched to early, so that there is an effect that the line interruption time can be shortened.

(Example) Hereinafter, the Example of this invention is described with reference to drawings.

FIG. 1 shows a radio transmitting / receiving apparatus of an uplink receiving station (master station, relay station) according to an embodiment of the present invention. Conventional example (fifth
Similar to the figure), the upper part of the figure shows the wireless transmitter part of the downlink, and the lower part of the figure shows the wireless receiver part of the uplink.

First, the difference from the conventional device will be described. In the wireless transmission device portion, the polling control circuit 24 is kept in order to perform the original polling, but this is not essential. This is because the method of the present invention has nothing to do with the presence or absence of the polling function. In that sense, the part related to polling is indicated by a broken line. Also, the frame pattern generator 23 '
Is similar to the conventional one in that it generates a control signal that defines each time slot in the radio frame, but in that time slot, in addition to the polling time slot P, as shown in FIG. The reception electric field detection time slot E is included.

On the other hand, in the wireless reception device part, a reception electric field detection timing generator 27 is provided in place of the polling timing generator 26 of the conventional example, and the electric field detection timing signal is transmitted at the time position of the reception electric field detection time slot to the cycle of the radio frame T _F. It is generated every time and is supplied to the alarm control circuit 25 as a sampling signal.

Further, FIG. 2 shows a wireless transmitting / receiving apparatus of a slave station according to an embodiment of the present invention. Also in this case, the part related to polling is indicated by a broken line. The polling information generator 35 is
It is the same as the conventional one. Further, in the present invention, the received electric field detection pattern generator 36 is provided. In response to a frame pulse signal formed and output by the frame synchronizing circuit 32, a burst signal for receiving electric field detection having a predetermined pattern is generated at a time position of a receiving electric field detection time slot, and the burst signal is received by a multiplexing circuit.
Output to 33.

In short, in the present invention, each slave station (2 ₁ , 2 ₃ , 2 ₄ , 2 ₅ to 2 _n )
The received electric field performs a transmission operation at the time position of the detected time slot E, also adapted to monitor the reception status of the uplink side of the receiver of the main station 1 and relay station 2 ₂ In the own station.

Next, referring to FIG. 3 as well, a monitoring system of the wireless reception device of the present invention will be described.

In the master station and the relay station, the frame signal having the structure shown in FIG. 3 (a) generated by the frame pattern generator 23 'is repeatedly transmitted to all the slave stations in the downlink.

On the other hand, in the slave station, the frame signal from the master station or the relay station is received by the antenna 28 and is introduced into the frame synchronization circuit 32 via the duplexer 29 and the receiver 30, where the cycle of the radio frame T _F. A frame pulse signal synchronized with
It is output to the received electric field detection pattern generator 36. And
The reception electric field detection burst signal generated by the reception electric field detection pattern generator 36 at the time position of the reception electric field detection time slot E is multiplexed with the main signal by the multiplexing circuit 33, and the transmitter 3
1. The signal is transmitted from the antenna 28 to the master station or the relay station via the duplexer 29.

That is, as shown in FIGS. 3B and 3C, all the slave stations
Transmits the reception field detection burst signal E 'to the master station 1 or repeater station 2 ₂ simultaneously with the reception field detection timeslot E for each radio frame.

Here, the received electric field detection burst signal E'is composed of an unmodulated wave or a signal modulated by a random signal.

It should be noted that P ₁ ′ to P _n ′ in FIGS. 3B and 3C are station information of the slave station with respect to the polling of the master station 1 as shown in the conventional example. That is, the master station 1 collects station information by polling each slave station as a form of normal communication, not for the purpose of monitoring shown in the conventional example. Station information
P ₅ ', the P _n', the P ₁ 'is the slave stations 2 _5, the 2 _n, indicates those received directly from the 2 ₁ and station information P _4' and the P ₃ 'relay station 2 ₂
The data received from the slave stations 2 ₄ and 2 ₃ via These are received together with the received electric field detection burst signal E'for each radio frame.

On the other hand, the relay station 2 _2, as shown in FIG. 3 (c), 'but is received in each radio frame, the station information P _4' received field detecting burst signal E and the P ₃ 'is a polling Since they are received when they are received, their reception timing is uncertain, and the reception interval may be considerably wide. As described above, the conventional method of monitoring by the polling method has a problem.

Now, in the radio receiving device part of the master station or relay station upstream side, the burst signal for receiving electric field detection from the slave station is transmitted to the antenna.
It is received at 17 and the receiver (19,2
0), the received electric field is detected as before,
The detected received electric field signal is input to the alarm controller circuit 25. As a result, in the alarm control circuit 25, the receiver 19
And the received electric field detection signals of the active system and the standby system from the same 20 are sampled with the electric field detection timing signal from the reception electric field detection timing generator 27, and the sampling result,
If the received electric field is not detected from the active system for a period of the radio frame period T _F or more, it is determined that the active system receiver has failed, and the reception switch 21 is switched to the standby system.

For example, as shown in FIG. 3 (d), the time at the receiver of the counted from left in the figure 3 th reception field detection burst signal E 'in the receiver on the uplink side of the relay station 2 ₂ t =
When a failure occurs at t ₁ , the receiving device cannot detect the fourth received electric field detecting burst signal E ′, so theoretically, the fourth received electric field detecting verse signal E ′ is detected. Time t = after the detection timing and before the detection timing of the fifth reception electric field detection burst signal E ′
Failure detection can be performed at t ₃ . In this case, the failure detection delay time (τ ₂ = t ₃ −t ₁ ) is equal to the radio frame T _F.
It will be about the period. Actually, this delay time τ ₂ is set for a plurality of periods of the radio frame T _F for safety. However, even if it does so, the delay time τ according to the method of the present invention
₂ it is clear that a much shorter time than the delay time tau ₁ according to a conventional method.

(Effects of the Invention) As described above, according to the monitoring system of the wireless reception device of the present invention, the delay time from the occurrence of a failure to its detection can be set to a plurality of periods of the wireless frame. This period is very short compared to the polling cycle in the conventional method.

Therefore, according to the method of the present invention, the period from the occurrence of a failure to its detection can be greatly shortened, and the standby system can be switched to early, so that there is an effect that the line interruption time can be shortened.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a radio transmitting / receiving apparatus of an uplink receiving station (master station, relay station) according to an embodiment of the present invention, FIG.
FIG. 1 is a block diagram showing the configuration of a wireless transmitter / receiver device for a slave station according to an embodiment of the present invention, FIG. 3 is an explanatory diagram of a monitoring system of a wireless receiver device of the present invention, and FIG. FIG. 5 is a block diagram showing the structure of an example of a multiplex communication system, FIG. 5 is a block diagram showing the structure of a conventional radio transmitter / receiver of an uplink receiving station (master station, relay station), and FIG. FIG. 7 is a block diagram of the configuration, and is an explanatory diagram of a monitoring method of a conventional wireless receiving device. 1 …… Master station, 2 ₁ , 2 ₃ , 2 ₄ , 2 ₅ 〜 2 _n …… Slave station, 2 ₂ …… Relay station, 11,12 …… Multiplex circuit, 13,14 …… Transmitter, 15… … Transmission selector, 16 …… Transceiver, 17 …… Antenna, 18 …… Hybrid, 19,20 …… Receiver, 21 …… Receive selector, 22
... Frame counter, 23 '... Frame pattern generator, 24 ... Polling control circuit, 25 ... Alarm control circuit, 26 ... Polling timing generator, 27 ... Reception electric field detection timing generator, 28 ... Antenna , 29 …… Transceiver, 30 …… Receiver, 31 …… Transmitter, 32 …… Frame synchronization circuit, 33 …… Multiplexing circuit, 34 …… Polling pattern detector, 35 …… Polling information generator, 36 ...... Reception electric field detection pattern generator, T _F ...... Radio frame, E ...... Reception electric field detection time slot, E '... Reception electric field detection burst signal, P ...... Polling time slot, P ₁ ′-
P _n ′ ... Station information.

Claims (1)

[Claims] 1. An uplink radio receiver in a multi-directional multiplex communication system in which communication control is performed by a demand assignment method in which a radio communication channel is allocated between a slave station and a master station only when a call originates at the slave station. A wireless receiver monitoring method for monitoring the occurrence of a fault; this wireless receiver monitoring method includes means for generating a received electric field detection burst signal to a wireless transmitter of each slave station; Means for transmitting the reception electric field detection burst signal in the reception electric field detection time slot set in each radio frame regardless of the presence or absence of the reception electric field detection time slot; Means for detecting the received electric field detection burst signal from a slot; and a received electric field detection bar for monitoring the received level of the detected received electric field detection burst signal. Means for determining a failure of the receiving device on the uplink side of the local station when the undetection of the reception of the received signal continues for a period exceeding a predetermined number of wireless frames; Monitoring method.