JPS6011858B2 - Remote monitoring device for simple repeaters - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a remote monitoring device for a simple relay station for remotely monitoring the status of a relay station in which a simple repeater for wireless FM communication is installed.

A simple repeater, also called a booster amplifier, is a repeater that amplifies the received radio waves as they are and retransmits them.

FIG. 1 is a block connection diagram showing an example of a simple repeater as a slave, in which 1 shows the main body of the simple repeater comprehensively, 2a,
2b, 2c, 2d are high frequency amplifiers, 3a, 3b
are high-frequency demultiplexing/combining circuits, and 4a and 4b are antennas, respectively. Conventionally, when a simple repeater like the one shown in this figure amplifies and retransmits the FM radio carrier wave as it is, the simple repeater transmits items that should be monitored among the relay station's status as a distant monitoring signal. was considered difficult.

For example, when a repeater performs heterodyne repeating, the frequencies of the input wave and output wave are different due to the frequency conversion circuit, so this separation could be easily achieved using a bandpass filter. In the simple repeater shown in Figure 1, the input wave and the output wave have the same frequency, and the input wave acts as an interference wave and degrades the communication quality of the output wave, making it difficult to use FM modulation and demodulation. It was difficult to transmit monitoring signals. This invention eliminates the above-mentioned drawbacks of the conventional simple relay station, and by adding a simple circuit, the status of the relay station where the simple repeater is installed is transmitted to the receiving station that receives the FM carrier wave output from this repeater. The purpose is to provide a device for transmission.

Embodiments of the present invention will be described below with reference to the drawings. Second
The figure is a block connection diagram showing a device provided on the relay station side in an embodiment of the present invention, in which the same reference numerals as in FIG. , 6 generally indicates a high frequency switching device, and 6a. 6b, 6c, and 6d are high frequency amplifiers 2, respectively.
a, 2b, 2c. This is a high frequency switch for 2d.

7 is an input gate circuit, 8 is a parallel input serial shift register, 9 is a clock pulse generation circuit, and 10 is a switch driving circuit.

In addition, A, B,...N' are signal input terminals corresponding to each item to be monitored among the status of this relay station, and the status indicated for each item is the logic "H" of the 1-bit signal or Assume that the state corresponds to logic "L". Further, when the state of a monitored item corresponds to logic "H", the signal input terminal (one of A, B, . . ., N) corresponding to that item is grounded. The input gate circuit 7 converts the presence or absence of grounding in the signal input state into the logic level of the signal "H" to "L", and also takes the logical sum of these signals and sends it to the parallel input circuit of the shift register 8. The shift register 8 sequentially converts the parallel input signals into serial outputs using the clock signal from the clock generation circuit 9 and sends them to the switch drive circuit 10. All the even-numbered parallel input terminals from the series output terminal of the shift register 8 are connected to logic "L" fog pressure, and the odd-numbered parallel input terminals from the series output terminal to a predetermined number are connected. (Terminals 1 and 3 in the example shown in Figure 2) are all connected to logic "H" voltage, and the first odd numbered number (terminal 5 in the example shown in Figure 2) that exceeds this predetermined number is connected to the logic "H" voltage. The logic signal of the logical sum of all the signals of terminals A, 8,...N is connected to the parallel input terminal of terminal A, 8, . . . Terminal A is the input terminal.
, B, . . . (N-1). For example, when terminal A is grounded, the serial output of shift register 8 will be logical. By repeating HLHL..., (20N) pulses appear.

The first two pulses out of (20N) are unrelated to the states of the signal input terminals A, B, ...N, as you can see from the connection in Figure 2, and such The meaning of generating pulses will be explained in a later section. Furthermore, when the signal input terminal N is grounded, the serial output of the shift register 8 is HLH.
(21) pulses appear in a pattern of LHLLL. The series pulse train led to the sliding door drive circuit 10' is current amplified and then drives the high frequency switch 6 to intermittent the carrier wave of the simple repeater by a predetermined number of pulses depending on the monitoring item.

It is assumed that a gate circuit for selecting which of the high-frequency switches 6a, 6b, 6c, and 6d is to be controlled is built into the switch drive circuit 10. FIG. 3 is a block connection diagram showing devices provided on the receiving station side in an embodiment of the present invention, in which 11 is an FM radio receiver, 12 is a receiving antenna, and 13 is a comprehensive remote monitoring received signal restoration circuit. 14 is an integration circuit, 15 is a timer, 16 is a counter reset pulse generation circuit, 17 is a latch read pulse generation circuit, 18 is a counter, 19 is a latch, 20 is a decoder, and 21 is a relay circuit.

Incidentally, the subordinate FM radio receiver 11 at the receiving station is also generally provided with a carrier wave level monitoring circuit and/or a noise monitoring circuit, so that the signals transmitted from the simple repeater shown in FIG. It is possible to detect discontinuity in the carrier wave and output it as a pulse signal Q shown in FIG. In this specification, the carrier wave level monitoring circuit and the noise monitoring circuit will be collectively referred to as the carrier wave level detection circuit. The pulse signal Q, which is the output of the carrier wave level detection circuit in the FM radio receiver 11, passes through the integrating circuit 14 and is counted by the counter 18.

The integrating circuit 14 is for removing narrow noise pulses (including pulses caused by short-time interruptions in carrier waves, etc.) superimposed on the pulse signal Q. As will be described later, the counter 18 has been reset in advance, so the integration circuit 14
The number of pulses of the pulse signal Q inputted through the counter 18 is counted, and when all the pulses have been counted, a pulse is output from the latch reading pulse generation circuit 17, and the parallel output of the counter 18 is input to the latch 19 and stored. The output of the latch 19 is decoded by the decoder 20 and sent to the relay circuit 21.
The signal is sent out and restored as a lamp display or earth signal output according to the monitoring item, and is held until the next state change occurs. The output of the integrating circuit 14 is led to a timer 15, and the timer 15 is activated by the first rising edge of the pulse train.

The output of timer 15 is the counter reset pulse generation circuit 1.
6 and a latch read pulse generation circuit 17, and are used to generate pulses for resetting the counter and for reading into the latch 19, respectively. That is, after the timer 15 is activated and the time elapses until the parallel inputs of the shift register 8 shown in FIG. After the input to the latch 19, a pulse is output from the counter reset pulse generation circuit 16 and the counter 1
Reset 8. Since the operation of the remote monitoring reception signal restoration circuit 13 is as described above, if a pulse signal with a small number of pulses is used, there is a risk that the counter 18 will erroneously count the pulses generated due to a disconnection of the line and erroneously display them as pulse signals. In order to prevent such a plot display, the number of pulses is increased by k (k=2 in the embodiment shown in FIG. 2).

In addition, in the input gate circuit 7, when the signal logic corresponding to the terminals A, B, . . . (for example, k+N11
When this number of pulses is detected by the decoder 20, its output is sent to the counter reset pulse generation circuit 16 and the latch read pulse generation circuit 17. In this case, the counter 18 is first reset and then the latch 19 is A read count value of 0 is stored in latch 19.

In the above embodiment, the shift register 8 is used in the far-field monitoring transmission signal generation circuit 5 to generate pulses, but if the number of items to be monitored is small, timers with different time constants for each item are provided to generate clock pulses. It is also possible to control the number of output pulses by gating the pulses sent out from the generation circuit with the timer output corresponding to the input signal item.
In addition, a current-controlled attenuator is used in place of the high-frequency switch 6 to reduce instantaneous interruptions in the line, and the operating point of the Schmitt trigger circuit of the carrier level detection circuit of the FM radio receiver 11 is adapted to the above-mentioned amount of attenuation. A similar effect can be obtained by setting.

As described above, according to the present invention, by providing a simple repeater with a simple long-distance monitoring transmission signal generation circuit and a high frequency switching device, the carrier level detection circuit (carrier level monitoring Since the remote monitoring circuit can be configured by simply adding a remote monitoring reception signal restoration circuit that restores the remote monitoring signal using the fault detection logic signal output from the circuit (or noise monitoring circuit), the device becomes inexpensive and the transmission speed is reduced. A remote monitoring device is obtained that can flexibly adapt to the selection of the number of items.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a conventional simple repeater, FIG. 2 is a block connection diagram showing a device provided on the relay station side in an embodiment of the present invention, and FIG. 3 is a block diagram showing an example of a conventional simple repeater. FIG. 2 is a block connection diagram showing devices provided on the receiving station side in the embodiment. In the figure, 1 is the simple repeater body, 2a, 2b" 2c, 2
d is a high frequency amplifier, 3a, 3b is a high frequency demultiplexing/combining circuit, 4a, 4b, 12 is an antenna,
5 is a remote monitoring transmission signal generation circuit, 6 is a high frequency switching device, 1
1 is an FM radio receiver (including a carrier wave level detection circuit);
Reference numeral 13 denotes a far-field monitoring received signal restoration circuit. Note that the same reference numerals in each figure indicate the same or equivalent parts. Festival l illustration 2 figure 3

Claims (1)

[Claims] 1. A remote monitoring transmission signal generation circuit that generates a predetermined number of pulses according to the items to be monitored among the conditions of a relay station where a simple repeater for wireless FM communication is installed, and this remote monitoring transmission signal. A high frequency switching device that modulates the amplitude of the FM carrier wave output from the simple repeater using the output pulse of the generator circuit;
A carrier wave level detection circuit for detecting the amplitude of the FM carrier wave provided in a receiving station that receives the M carrier wave, and a distant monitoring reception signal restoration circuit for restoring the signal according to the number of pulses detected from the carrier wave level detection circuit. A remote monitoring device for a simple repeater, which is characterized by: