JP2900642B2 - Fault diagnosis circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fault diagnosis circuit, and more particularly to a fault diagnosis circuit for a multi-beam antenna receiver.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a plurality of antennas 1a, 1b,..., 1n and converters 2a, 2b,.
In the case where a fault diagnosis circuit is provided in the multi-beam antenna receiver constituted by the antennas n and the receiver 3, each antenna 1a, 1
, 1n and converters 2a, 2b,..., 2n are provided with test signal generators 11 for inputting test signals, respectively. The test is performed by receiving the test signal generated from the test signal generator 11 by the receiver 3.

[0003]

In such a conventional fault diagnosis circuit, since the test signal generated from one test signal generator 11 is input to the subsequent stage of each antenna, the antennas 1a, 1b, , 1n, there is a problem that it cannot be detected if any one of them fails.
An object of the present invention is to provide a failure diagnosis circuit that can detect a failure in an antenna.

[0004]

SUMMARY OF THE INVENTION A fault diagnosis circuit according to the present invention detects a maximum amplitude based on outputs from converters provided for a plurality of antennas, and detects a channel (CH) number corresponding to the antenna. A maximum amplitude value calculation circuit that outputs
An amplitude value generation circuit that generates an ideal amplitude value of each CH from the maximum amplitude CH number, a comparison circuit that compares the amplitude value of each CH from the converter with the ideal amplitude value and outputs an amplitude difference, An average value calculating circuit for calculating an average value of the amplitude difference from the amplitude difference of the CH;
An angle calculation circuit for calculating the angle of the amplitude difference by inputting the number and the amplitude difference of each CH, a histogram generation circuit for calculating the histogram by inputting the angle of each CH, and outputting the angle of the maximum number of times, A judgment circuit for judging an error from the angle of CH and the angle of the maximum number of times.

[0005]

According to the present invention, the amplitude value of a signal received by each antenna is compared with the ideal amplitude value based on CH which is the maximum amplitude value to determine the amplitude difference. Utilizing that the amplitude difference of each CH has a predetermined relationship, the failure of the CH is diagnosed based on the difference of the amplitude difference.

[0006]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a block circuit diagram of one embodiment of the failure diagnosis circuit of the present invention. In the figure, a plurality of antennas 1a, 1
, 1n, converters 2a, 2b,..., 2n for converting signals output from the antenna into digital signals, and a receiver 3 for performing a receiving operation by performing an operation based on the converted signals.
These form a multi-beam antenna receiver. A maximum amplitude value calculation circuit 4 and a comparison circuit 6 are connected to the subsequent stage of each of the converters 2a, 2b,..., 2n. The maximum amplitude value calculation circuit 4 detects the maximum amplitude of the converted digital signal and detects its antenna number, that is, the channel (C).
H) Number can be output. The maximum amplitude value calculation circuit 4 is connected to an amplitude value generation circuit 5 for generating an ideal amplitude value of each CH from the maximum amplitude CH number.

[0007] The comparison circuit 6 is provided for each channel from the converter.
And an ideal amplitude value from the amplitude value generating circuit 5 to output an amplitude difference. This includes an average value calculation circuit 7 for calculating an average value of the amplitude difference from the amplitude difference of each channel, Calculation circuit 8 for inputting the average value of the data, the CH number of the maximum amplitude, and the amplitude difference of each CH and calculates the angle of the amplitude difference
, A histogram generation circuit 9 that calculates the histogram by inputting the angle of each CH and outputs the angle that is the maximum number of times
And a judgment circuit 10 for judging an error from the angle of each CH and the angle of the maximum number of times.

According to this configuration, the antennas 1a, 1b,
, 1n are transmitted to converters 2a, 2b,.
The signal is converted into a digital amplitude value by 2n, and is input to the maximum amplitude value calculation circuit 4 and the comparison circuit 6. The maximum amplitude value calculation circuit 4 detects the maximum amplitude of the input digital amplitude value,
The CH number having the maximum amplitude is output to the amplitude value generation circuit 5. The amplitude value generation circuit 5 outputs the ideal amplitude value PAn and the maximum amplitude antenna azimuth MAX AZ received by each antenna with the antenna beam nose having the maximum amplitude as the true direction from the CH number having the maximum amplitude.

On the other hand, the digital amplitude value and the ideal amplitude value PAn input to the comparison circuit 6 are compared for each CH number, and the respective amplitude differences are output to the average value calculation circuit 7. The average value calculation circuit 7 calculates the average value of the amplitude difference of each channel, and outputs the average value and the amplitude difference of each channel to the angle calculation circuit 8. As shown in FIG. 2, the angle calculation circuit 8 calculates the average value and the MAX value from the amplitude difference, the average value, and the MAX AZ of each CH.
Except for the CH having the maximum amplitude with the intersection of AZ as the origin, the angle Δθn of each CH is calculated and output to the histogram generation circuit 9 and the determination circuit 10.

The histogram generation circuit 9 generates an angle Δθ _HIST having the largest number within the same angle range, and outputs this to the determination circuit 10. The determination circuit 10 determines the angle Δθ of each CH.
n and the angle Δθ _HIST having the largest number are compared, and an antenna number whose difference is out of a predetermined allowable range value is output as a faulty antenna number. In this embodiment, the antenna of No. 6 has deteriorated and is diagnosed as having failed. As described above, by comparing the amplitude value of the received radio wave with the amplitude value of the ideal pattern, it is possible to detect an antenna number that causes abnormal gain and diagnose this as a failure.

[0011]

As described above, according to the present invention, the amplitude value of a signal received by each antenna is compared with the ideal amplitude value based on CH which is the maximum amplitude value. Since the failure of the antenna is diagnosed based on this, it is possible to detect the antenna with abnormal gain by using the arriving radio wave and to diagnose the failure clearly. At the same time, it is possible to diagnose a gain abnormality due to multipath, shadowing, or the like. Further, the present invention has an effect that a device for generating a test signal can be dispensed with.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of an embodiment of a failure diagnosis circuit according to the present invention.

FIG. 2 is a diagram for explaining signal processing in the present invention.

FIG. 3 is a block circuit diagram of a conventional failure diagnosis circuit.

[Explanation of symbols]

 1a-1n Antenna 2a-2n Converter 3 Receiver 4 Maximum Amplitude Calculation Circuit 5 Amplitude Generation Circuit 6 Comparison Circuit 7 Average Calculation Circuit 8 Angle Calculation Circuit 9 Histogram Generation Circuit 10 Judgment Circuit

Continuation of front page (56) References JP-A-4-332204 (JP, A) JP-A-4-235371 (JP, A) JP-A-2-208582 (JP, A) JP-A-2-129577 (JP) JP-A-2-90704 (JP, A) JP-A-63-142703 (JP, A) JP-A-63-142702 (JP, A) JP-A-63-40403 (JP, A) 63-40402 (JP, A) Japanese Utility Model Hei 10-106481 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01S 7/00-7/42 G01S 13/00-13 / 95 H01Q 3/26 H01Q 21/00

Claims (2)

(57) [Claims] 1. A plurality of antennas, a converter for converting a signal output from the antenna to a digital signal, a receiver for performing a receiving operation by performing an operation based on the converted signal, and an output from the converter. A maximum amplitude value calculation circuit for detecting a maximum amplitude based on the antenna and outputting a channel (CH) number corresponding to the antenna, an amplitude value generation circuit for generating an ideal amplitude value of each CH from the maximum amplitude CH number, A comparison circuit that compares the amplitude value of each channel from the converter with the ideal amplitude value and outputs an amplitude difference; an average value calculation circuit that calculates an average value of the amplitude difference from the amplitude difference of each channel; An angle calculation circuit that inputs the average value of the CH, the CH number of the maximum amplitude, and the amplitude difference of each CH to calculate the angle of the amplitude difference, and inputs the angle of each CH to calculate the histogram, and determines the angle that is the maximum number of times. Hist to output A failure diagnosis circuit comprising: a gram generation circuit; and a determination circuit for determining an error based on an angle of each CH and an angle which is the maximum number of times. 2. The fault diagnosis circuit according to claim 1, wherein the number of antennas is four or more.