JPS58140661A - Automatic real-time calibration type range finder - Google Patents

Abstract

PURPOSE:To measure the range up to an object with high precision, by passing signals of slightly different frequencies through exactly the same route and measuring delay time on real-time basis. CONSTITUTION:After a transmission frequency is modulated by a tone for transmission distance measurement and amplified, the resulting signal is sent out of an antenna 1. The sent radio wave arrives at the object and is relayed and received by the antenna 1 again. The received signal is demodulated by a receiver 10 after low-noise amplification and frequency conversion and a tone extractor 11 extracts the tone for range measurement. The output signal of a transmitting amplifier 2 is distributed and extracted by a coupler 15 and converted to such a frequency that the receiver 10 can not acquires it; and the resulting signal is supplied to a coupler 16 for low-noise amplification and frequency conversion together with the received signal, a receiver 8 imposed demodulation, and a tone extractor extracts the tone for range measurement. The tones extracted by extractors 9 and 11 are supplied to phase meters 12 and 13 to measure their phase differences from the tone for the transmission distance measurement, and those measured values are supplied to a subtracter 14 to obtain the difference; and the delay time variation of a transmitting and receiving system circuit is canceled to realize high-precision measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-precision distance measuring device that measures the distance to an object having a moving radio wave repeater.

Conventional devices of this type were calibrated before operation for gR1#, which is the delay time caused by temperature changes in the transmitting/receiving hardware, elapsed time, and changes in other environmental conditions. Regarding the latter change 1, all of them result in distance measurement errors and become obstacles to high-precision distance measurement.It is technically very difficult to suppress this, and even if it is possible, it is very costly. It had the disadvantage of being.

The present invention eliminates these drawbacks and makes it possible to easily create a device in which the delay time fluctuation of the transmitter/receiver circuit after calibration before operation does not become a constant error of distance −j, without any special consideration in designing the transmitter/receiver circuit. The purpose is to provide this product at a low cost, and the drawings will be explained in detail below.

FIG. 2 shows an embodiment of the present invention, in which 1 is an antenna, 2 is a transmitting amplifier, 3 is a modulator, 4 is a tone generator, 5 is a frequency converter, 6 is a low noise amplifier, and 7 is a receiving frequency. converter,
8 is a first receiver, 9 is a first tone extractor, 10 is a second receiver, 11 is a second tone extractor, 12 is a first phase meter, 13 is a second phase meter, 14 is a subtracter, 15 is a first coupler, and 16 is a coupler of irises 2.

To operate this, a modulator modulates the transmission frequency using a transmission distance measurement tone generated by a tone generator, and the signal is amplified by a transmission amplifier and then sent out from an antenna. Radio waves transmitted from an antenna reach a target object (such as an artificial satellite), are relayed, and are received by the antenna again. The received signal is low-noise amplified, frequency converted, and demodulated by a second receiver, and a distance measurement tone is extracted by a second tone extractor.

On the other hand, the output signal of the transmitting amplifier is distributed and extracted by the first coupler and converted into a frequency that is received by the antenna and a frequency that cannot be captured by the second receiver, and is then received in the air. The signal is combined with the second combiner, low-noise amplified, frequency converted, demodulated by the first receiver, and a distance measurement tone is extracted by the first tone extractor.

The distance measurement tones extracted by the first tone extractor and the distance measurement tones extracted by the second tone extractor are the first . Transmission distance # by second phase meter
Measure the phase difference of the J periodic tone, and use a subtracter to subtract the IIIJ constant value obtained by the first phase meter from the measurement value obtained by the second phase meter. With this configuration, delay time fluctuations in the transmitting and receiving circuits are always canceled.

As explained above, it is possible to measure the delay time in real time by sending signals with slightly different frequencies through the same route.
Therefore, the distance to the object can be measured with high precision without causing a distance error due to delay time fluctuations of the transmitting/receiving hardware.

[Brief explanation of drawings]

FIG. 1 is a system diagram of a conventional distance measuring device, and FIG. 2 is a system diagram of an embodiment of the present invention. In addition, in the figure, 1... antenna, 2...
...Transmission amplifier, 3...Modulator, 4...
... Tone generator, 5 ... Frequency converter, 6.
...low noise amplifier, 7 ... reception frequency converter, 8 ... first receiver, 9 ... first tone extractor, 10. ...Second receiver, 1
1°・°°°°Second tone extractor, 12...
First phase needle, 13...Second phase meter, 14.
...subtractor, 15°°°°°°first combiner, 1
6... Second coupler, 17... Sui,
Te, deru・

Claims (1)

[Claims] a transmission distance #j periodic tone generator; a modulation unit that modulates a transmission signal with the tone; an amplification unit that amplifies the output of the modulation unit; an antenna unit that transmits the output signal of the amplification unit; a first coupling section that distributes and extracts the output signal of the amplification section; a frequency conversion section that converts the output signal of the first coupling section into a first frequency; and a second frequency signal received from the antenna. a second coupling section that couples the outputs of the frequency conversion section; a low-noise amplification section that amplifies the output signal of the second coupling section; and a reception frequency conversion that converts the output of the low-noise amplification section to an intermediate frequency. a first receiving section that demodulates the signal of the first frequency; a first tone extracting section that extracts a first reception distance measuring tone from the output of the first receiving section; a second demodulating signal of two frequencies;
a second tone extraction section that extracts a second reception distance measurement tone from the output of the second reception section; and a second tone extraction section that extracts a second reception distance measurement tone from the output of the second reception section; a first phase meter 6111 unit that measures a phase difference; a second phase measurement unit that measures a phase difference between the transmission distance 11111J regular tone and the second reception distance measuring tone; and means for calibrating delay time fluctuations in a transmitting/receiving circuit during distance measurement by subtracting the phase value of the measuring section from the phase value of the second phase meter side section.