JPS6053932B2 - receiver monitoring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a reception monitoring system at any time for a transmitter that transmits radio waves only during communication and a receiver that performs wireless communication, and the receiver is always on standby. It is.

Conventionally, this type of receiver is always on standby, so even if radio waves are actually input, it is impossible to tell if the receiver is abnormal. There was an inconvenience that the abnormality could not be determined. SUMMARY OF THE INVENTION An object of the present invention is to provide a receiver monitoring device that eliminates the above-mentioned disadvantages. The present invention is characterized in that when the receiver is on standby, it is determined whether the receiver is normal or not, and a notification is displayed inside the receiver or a notification is sent to the outside of the receiver.

The present invention will be described in detail below with reference to the drawings. 1st
The figure is a block diagram showing an example of a conventional receiver.

In the figure, an input radio wave from a receiving antenna 1 is amplified by a high frequency amplifier circuit 2, mixed with a signal from a local oscillation circuit 4 by a mixing circuit 3 to become an intermediate frequency, and after being amplified by an intermediate frequency amplifier circuit 5, The frequency discrimination circuit 6 demodulates the signal, and the demodulated low frequency signal is applied to the low frequency amplification circuit 7. On the other hand, changes in the electric field from the intermediate frequency amplification circuit 5 are detected by the radio wave detection circuit 9, and an output is sent out when the input electric field is equal to or higher than a set value. Therefore, it can be used simply to determine the presence or absence of an input electric field, but cannot be used to monitor the receiver. FIG. 2 is a block diagram showing an example of a receiver according to the present invention.

When the receiver is in a standby state, first, the control signal applied to the control signal input 16 is input to the receiving circuit 13.
The control circuit 13 drives the oscillation circuit 12 for a predetermined time at any time when the receiver is in a standby state. The predetermined time is selected within a range that is longer than the operating time of the radio wave detection circuit 9 and does not interfere with wireless communication between the transmitter and the receiver. The oscillation circuit 12 supplies an input electric field higher than the level set in the radio wave detection circuit 9 to the receiver through the coupling circuit 11, and the receiver receives this input radio wave. The radio wave detection circuit 9 in the receiver detects this change in the input electric field and inputs it to the input terminal of the signal comparison circuit 14. On the other hand, the signal comparison circuit 14 compares the control signal input to the other input terminal with the input signal from the radio wave detection circuit 9, and when there is no detection output from the radio wave detection circuit 9 when the control signal is input, the receiver Determines an abnormality and sends a report to an object outside the receiver. In this embodiment, the control signal for driving the oscillation circuit may be sent out once or more times while the receiver is on standby, and the control signal for driving the oscillation circuit may be transmitted by changing the electric field. , but not limited to,
In FIG. 1, the high frequency component noise demodulated by the frequency discrimination circuit 6 and the noise component within the voice band may be used. In addition to reporting an abnormality to the outside of the device, it may also be displayed on the inside of the receiver. As explained above, according to the receiver of the present invention, abnormalities in the receiver can be detected early, and the time required for maintenance and inspection of the receiver can be reduced.

[Brief explanation of drawings]

FIG. 1 is an example of a block diagram showing an example of a conventional receiver, and FIG. 2 is an example of a block diagram showing an example of the receiver of the present invention. 1... Receiving antenna, 2... High frequency amplification circuit, 3... Mixing circuit, 4... Local oscillation circuit, 5... Intermediate Frequency amplification circuit, 6...
...Frequency discrimination circuit, 7...Low frequency amplification circuit,
8...Low frequency output terminal, 9...Radio wave detection circuit, 10...Detection output terminal, 11...Coupling circuit, 12...Oscillation circuit, 13 ...Control circuit, 14...Signal comparison circuit, 15...
Comparison output terminal, 16... Control signal input terminal.

Claims (1)

[Claims] 1. In a receiver that performs wireless communication with a transmitter that transmits radio waves only during communication, an oscillation circuit that oscillates at a frequency equivalent to the receiving frequency of the receiver, and a control circuit that controls the oscillation circuit using a control signal. a coupling circuit for supplying the oscillation circuit output to the receiver; a circuit for detecting the oscillation frequency; and a comparison circuit for comparing both the output of the detection circuit and a control signal applied to the control circuit. has
A receiver monitoring device characterized in that when monitoring a receiver, the receiver that is always on standby is monitored by the output of the comparison circuit.