JPS63217735A - Slave station equipment for time division multi-direction multiplex communication system - Google Patents

Abstract

PURPOSE:To surely detect a fault in its own station without requiring a separate channel for supervisory by using the time slot of a polling channel not applying the call to its own station so as to transmit/receive the supervisory signal of its own station. CONSTITUTION:The supervisory signal of a slave station from a supervisory signal generating circuit 1 is processed by a timing division multiplexing circuit 3 and an IF modulation circuit 4 controlled by a polling control circuit 8 via a supervisory multiplexing circuit 2 in each slave station. Then only the IF signal of supervisory section is extracted from a gate circuit 5 controlled by the circuit 8 and transmitted to a master station by using a time slot of polling channel. The IF reception signal corresponding to loopback from a master station is received and demodulated by using the time slot of the polling channel by a time division multiplexing circuit 6 and a demodulation circuit 7 or the like controlled by the circuit 8 and a fault detection circuit 9 from the demodulation signal is detected surely without providing a supervisory channel and the signal transmission in a slot other than the assigned slot disturbing the communication of other slave stations is prevented.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a slave station device for time division multidirectional multiplex communication system,
In particular, it relates to a time-division multi-directional multiplex communication system slave station device that is equipped with a means for detecting a failure within each slave station in one master station and a plurality of slave stations that employ the time-division multi-directional multiplex communication system. .

[Conventional technology]

FIG. 3 is a diagram illustrating a time division multiplex communication system to which the present invention is applied. In the figure, a master station M sends out time-division signals simultaneously in multiple directions, and each slave station Al to AN synchronizes with the signal sent from the master station M and regenerates the timing signal. Take out the signal for the time being on the station side. Furthermore, each slave station Al to AN transmits burst signals Sl to SN for the time of subframes SF to SFN previously assigned to each slave station based on the above timing signal as a reference, and the master station M transmits burst signals Sl to SN to each slave station A1 to AN. Burst signal 81 sent from
~SN are controlled so that they are arranged in order on the time axis. F in the figure indicates one frame of the signal sequence, and S F 1. S
F2 to SFX are subframes and indicate the time allocated to each slave station A, , A2 to AN within one frame. Further, 5F-P is a polling channel commonly used by each slave station, and the figure shows, as an example, a case where the master station M is polling the slave station A2. Generally, the frame structure of the signal train from the master station to the slave station and the signal train from the slave station to the master station are the same, and the frequencies of their respective carrier waves are changed for transmission and reception.

[Problem that the invention seeks to solve]

However, in the above-mentioned time division multiplex communication system, the signals from each slave station to the master station are controlled at each slave station so that they arrive at the time position assigned to each slave station at the input of the master station. There is. Therefore, if a signal is sent at a time other than the time allotted to the own station due to a failure in the slave station, it will collide with the signals sent from other slave stations to the master station, and the communication of other slave stations will be interrupted. This can cause interference, especially if it is accidentally applied to polling channel communication, which has the drawback that the master station cannot manage and control each slave station, which can have a great impact on the entire system. Each slave station has a problem in that it is necessary to reliably detect a failure within the local station in order to stop transmitting signals from the local station in the event of a failure in the local station.

An object of the present invention is to provide time-division multidirectional multiplexing in which failures within each slave station can be detected by looping back the supervisory signal generated within the slave station to the receiving side before transmission and detecting whether or not there is an error in the looped back supervisory signal. An object of the present invention is to provide a slave station device for a communication method.

[Means for solving problems]

The slave station device for time-division multiplex communication system of the present invention is composed of one master station and a plurality of slave stations. In a time-division multiplex communication system slave station equipped with a polling channel for managing and controlling the slave station using a polling method, a supervisory signal generation circuit that generates a supervisory signal for monitoring the presence or absence of a failure within the own station; A supervisory signal multiplexing circuit that time-division multiplexes the supervisory signal output from the supervisory signal generation circuit into the time slot of the polling channel that sends it to the master station, and a modulation system that modulates the output signal of the supervisory signal multiplexer and outputs an IF multiplied signal. a gate circuit for extracting the IF multiplied signal of the section of the monitoring signal which is time-division multiplexed with the IF multiplied signal output from the modulation circuit; and an I of the section of the monitoring signal extracted by the gate circuit.
A time-division multiplexing circuit that time-division multiplexes the F-multiplexed signal, a signal received from the master station and converted into the IF-multiplexed signal, a demodulation circuit that demodulates the output signal of the time-division multiplexing circuit, and a demodulation circuit that demodulates the output signal of the demodulation circuit. and a fault detection circuit that monitors time-division multiplexed monitoring signals and detects the presence or absence of errors.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of a slave station device in which the present invention is applied to the time division multiplex communication system shown in FIG. 3. In FIG. 1, reference numeral 1 denotes a supervisory signal generation circuit that generates a supervisory signal having a specific pattern for monitoring the presence or absence of a fault within its own station according to a timing control signal from a polling control circuit 8; A supervisory signal multiplexing circuit 3 time-division multiplexes the output supervisory signal into an input signal sent to the master station; A time division multiplexing circuit that time division multiplexes the output signal; 4 is a modulation circuit that modulates the output signal from the time division multiplexing circuit 3 and outputs the IF multiplied signal; 5 is a modulation circuit that performs time division multiplexing on the output signal from the modulation circuit 4; a gate circuit that separates sections of the monitoring signal time-division multiplexed in the monitoring signal multiplexing circuit 2 and sends other sections of the signal to a transmission output circuit for a master station;
is a time division multiplexing circuit which time division multiplexes the IF multiplied signal of the monitoring signal separated from the gate circuit 5 into the signal received from the master station and converted into an IP signal according to the timing control signal from the polling control circuit 8. 7 is a demodulation circuit that demodulates the output IF signal of the time division multiplexing circuit 6; 9 is a failure detection circuit, which is time division multiplexed with the output signal of the demodulation circuit 7 according to a timing control signal from the polling control circuit 8; A circuit for monitoring the supervisory signal and detecting whether or not there is an error in the supervisory signal; 8 is a polling control circuit which sends a volink response signal in response to a polling call from the master station to the time division multiplexing circuit 3, and a timing control signal for the supervisory signal; This circuit outputs the signal to the supervisory signal generation circuit 1, the gate circuit 5, the time division multiplexing circuit 6, and the fault detection circuit 9.

2 is a timing chart showing an example of the signals of the main part of FIG. 1. FIG. 2(a) shows the input signal SSI of FIG. 1, and FIG. The signal T, (c) is the output signal of the time division multiplexed northern circuit I ¥83,
The input signal SS, , the monitoring signal T, and the baud link response signal PR are time-division multiplexed.

Further, FIG. 2(d) shows a signal obtained by receiving a transmission signal from the master station and converting it into an IP signal, which is used to sequentially call the slave stations A1-1, At, At+1 on the polling channel 5F-P. This shows that PR+ and PR+++ are being sent. FIG. 2(e) shows the output signal of the time division multiplexing circuit 6, which is a signal sent from the master station shown in FIG. This shows a state in which the supervisory signal T shown in FIG. 2(C) is time-division multiplexed in the time slots in which calls are made to At+1 and At+1.

As is known from the explanation of FIGS. 1 and 2 above,
In the slave station device of the present invention, if a fault occurs in at least one of the functional circuits shown in FIG. 1, a signal error will occur in the monitoring signal T, which will be detected by the fault detection circuit 9 as a device fault.

〔Effect of the invention〕

As explained above, the present invention eliminates the need for a separate channel for monitoring by transmitting and receiving supervisory signals for local monitoring using the time slots of the polling channel in which calls are only being made to the local station. Therefore, there is an effect that failures within the own station can be detected efficiently and reliably.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a slave station device for time division multiplex communication system according to the present invention, FIG. 2 is a timing chart showing an example of signals of each main part of FIG. 1, and FIG. FIG. 2 is a diagram illustrating a time division multiplex communication system to which the present invention is applied. DESCRIPTION OF SYMBOLS 1... Monitoring signal generation circuit, 2... Monitoring signal multiplexing circuit, 3.6... Time division multiplexing circuit, 4... Modulation circuit, 5... Gate circuit, 7... Demodulation Circuit, 8... Polling control circuit, 9... Failure detection circuit.

Claims (1)

[Claims] Consisting of one master station and a plurality of slave stations, the propagation path signal train between the master station and the slave stations includes a polling channel for managing and controlling each slave station from the master station by a polling method. A slave station using a time-division multidirectional multiplex communication system includes a supervisory signal generation circuit that generates a supervisory signal for monitoring the presence or absence of a fault within its own station, and a supervisory signal output from this supervisory signal generation circuit that is transmitted to the master station. a supervisory signal multiplexing circuit that time-division multiplexes the polling channel time slots in the signal train sent to the monitor, a modulation circuit that modulates the output signal of the supervisory signal multiplexer and outputs an IF signal, and an output signal from the modulation circuit. a gate circuit that extracts the IF signal in the section of the monitoring signal from the IF signal received by the gate circuit; A time division multiplexing circuit for multiplexing, a demodulation circuit for demodulating the output signal of this time division multiplexing circuit, and a fault detection for detecting an error in the monitoring signal that is time division multiplexed with the output signal of this demodulation circuit. A slave station device for a time division multidirectional multiplex communication system, characterized in that it has a circuit.