JPS63175789A - Distance measuring instrument - Google Patents

Abstract

PURPOSE:To calculate an accurate distance by considering the phase difference between the sent and received signals of a distance measurement tone signal synchronized with a PCM information communication signal as to the distance found from the reciprocation time of the PCM information communication signal. CONSTITUTION:The distance measurement tone signal STT is generated 11 according to the signal CT of an arithmetic processing control part 9 to output a PCM information signal SPT containing a prescribed signal, and a transmission timing signal TT synchronized with the trailing edge of a frame synchronizing pattern signal F is generated. The signals STT and SPT are put together and sent 3 to a target 10, and a sent-back wave is received 4, so that the STR and SRR are separated 5. A demodulation part 6 generates a reception timing signal TR and the PCM information signal D synchronized with the trailing edge of the signal F of a signal SPR. A clock CK is counted 7 with a signal TT and the counting is stopped with a signal TR, and a time difference signal between the sent and received waves determined by the counting is outputted 7. A measurement part 8 measures the phase difference between the signal STT and STR repeatedly for prescribed period PM according to the signal TR and calculates the mean value. A control part 9 accurately calculates the distance to a target by performing specific arithmetic with those signals. This constitution does not make circuits complex and the distance is accurately measured at a high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a distance measuring device, and more particularly to a distance measuring device that measures the distance to a target using a ranging tone signal.

[Conventional technology]

Conventionally, in order to remove ambiguity (phase uncertainty), this type of distance measuring device uses a reference ranging tone signal followed by an ambiguity removal tone having a wavelength that is an integral multiple of this signal. Sequentially transmit signals, measure the phase difference between these signals and the returned signals individually, and calculate the distance at which ambiguity has been removed by combining these measurement results, or , PN (Pseudo
No. 1) The configuration was such that a code signal was transmitted and the distance from which ambiguity was removed was calculated by using the delay time of the received PN code signal.

[Problem that the invention seeks to solve]

In order to eliminate ambiguity, the conventional distance measuring device described above generates and transmits a tone signal having a wavelength that is an integral multiple of this signal, following a reference ranging tone signal, and The configuration is such that the phase difference between the received tone signal and the received tone signal is measured for each tone signal, so in order to perform high-precision and long-distance measurement, more tone signals are required to remove ambiguity. However, there is a disadvantage that the measurement time becomes longer.

Furthermore, when using a PN code signal, the longer the measurement distance, the longer the PN code period becomes, making it difficult to capture the returned PN code, and the circuit becomes more complex.

SUMMARY OF THE INVENTION An object of the present invention is to provide a distance measuring device that can measure with high accuracy in a short time and can prevent the circuit from becoming complicated.

[Means for solving problems]

The distance measuring device of the present invention includes a ranging tone signal generating section that generates a ranging tone signal of a predetermined frequency in response to a transmission control signal, and a PCM data communication signal including a frame synchronization pattern signal and PCM data in response to the transmission control signal. and a PCM data signal transmitter that outputs a transmission timing signal synchronized with the frame synchronization pattern signal; a transmitting section that emits radio waves; a receiving section that receives and processes the return radio waves from the target; a separation filter that separates the ranging tone signal and the PCM data communication signal from the output signal of the receiving section; A PCM that inputs the PCM data communication signal received from the filter and outputs a reception timing signal synchronized with the frame synchronization pattern signal of this PCM data communication signal.
a data demodulation section; a time interval counter that starts counting a clock signal according to the transmission timing signal, stops counting according to the reception timing signal, and outputs a time difference signal; and the distance measurement tone signal generation section for a predetermined period of time according to the reception timing signal. a phase difference measurement unit that measures the phase difference between the ranging tone signal from the rangefinding tone signal and the ranging tone signal received from the separation filter and outputs a phase difference signal;
It has an arithmetic processing control section that outputs the transmission control signal and calculates the distance to the target object from the time difference signal and the phase difference signal.

〔Example〕

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

FIG. 1 is a block diagram showing one embodiment of the present invention.

The ranging tone signal generating section 1 outputs a ranging tone signal STT of a predetermined frequency in accordance with a transmission control signal CT from the arithmetic processing control section 9.

The PCM data signal sending unit 2 outputs a PCM data communication signal SpT including a bit synchronization pattern signal B, a frame synchronization pattern signal F following this, and a <:PCM data signal following this, in accordance with the sending control signal CT. and outputs a transmission timing signal TT synchronized with the end edge of the frame synchronization pattern signal F.

The transmitter 3 synthesizes the ranging tone signal STT and the PCM data communication signal SPT, and emits radio waves of the synthesized signal to the target object 10.

The receiving unit 4 receives and processes the radio waves returned from the target object 10, and outputs the received radio waves.

Separation filter 5 separates the output signal from receiving section 4 into ranging tone signal STR and PCM data communication signal SPR.

The PCM data demodulation unit 6 inputs the received PCM data communication signal SPR, outputs a reception timing signal Tλ synchronized with the end edge of the frame synchronization pattern signal F of this PCM data communication signal SPR, and also Output.

The time interval counter 7 starts counting the clock signal CK in response to the transmission timing signal Tt, stops this counting in response to the reception timing signal TR, and the radio wave emitted from the transmitter 3 determined by this count number passes through the target object 10 The time required for the radio wave to reach the receiver 4, that is, the time difference between the emitted radio wave and the received radio wave, is output as a time difference signal.

The phase difference measuring section 8 calculates a plurality of phase differences between the ranging tone signal STT from the ranging tone signal generating section 1 and the ranging tone signal STR received from the separation filter 5 for a predetermined period PM according to the reception timing signal TR. Measured twice, averaged, and output as a phase difference signal.

The arithmetic processing control section 9 outputs a transmission control signal CT that determines the start of distance measurement, and also inputs the time difference signal from the time interval counter 7 and the phase difference signal from the phase difference measurement section 8, and calculates based on these signals. A predetermined calculation is performed to calculate and output the accurate distance to the target.

FIG. 2 is a timing diagram for explaining the operation of this embodiment.

The count period t of the clock signal CK of the time interval Carantuff from the rise of the transmission timing signal TT to the rise of the reception timing signal TR corresponds to the round trip distance to the target object 10. By using the PCM data communication signal, a relatively high frequency ranging tone signal can be used, so calculate the approximate distance using this count number, and add the frequency of the clock signal CK and the ranging tone signal to this count number. By incorporating relationships, phase difference measurement results, etc., accurate distances can be calculated.

〔Effect of the invention〕

As explained above, the present invention has a configuration that calculates an accurate distance by incorporating the phase difference between the transmitting and receiving signals of the ranging tone signal synchronized with the PCM communication signal into the distance determined from the round trip time of the PCM data communication signal. By doing this, even if the distance is long, only one ranging tone signal with a relatively high frequency is required, and a PN code with a long period is not required, so distance measurement can be carried out in a short time without complicating the circuit. Moreover, it has the effect of being able to perform the process with high precision.

There is also the effect that distance measurement PCM data communication can be performed simultaneously.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a timing diagram for explaining the operation of the embodiment shown in FIG. DESCRIPTION OF SYMBOLS 1... Distance measurement tone signal generation section, 2... PCM data signal transmission section, 3... Transmission section, 4... Receiving section, 5...
- Separation filter, 6... PCM data demodulation section, 7...
- Time interval counter, 8... Phase difference measuring section, 9... Arithmetic processing control section, 10... Target object. 1, ~

Claims (1)

[Claims] a ranging tone signal generator that generates a ranging tone signal of a predetermined frequency in response to a transmission control signal;
A PC that outputs a CM data communication signal and a transmission timing signal synchronized with the frame synchronization pattern signal.
M data signal transmitter, the ranging tone signal and the PC
A transmitting section that synthesizes the M data communication signal and emits radio waves of the synthesized signal to the target object, a receiving section that receives and processes the return radio waves from the target object, and a receiver that performs measurement from the output signal of this receiving section. A separation filter that separates a range tone signal and a PCM data communication signal, and a PCM that inputs the received PCM data communication signal from this separation filter and outputs a reception timing signal synchronized with a frame synchronization pattern signal of this PCM data communication signal. a data demodulation section; a time interval counter that starts counting a clock signal according to the transmission timing signal, stops counting according to the reception timing signal, and outputs a time difference signal; and the distance measurement tone signal generation section for a predetermined period of time according to the reception timing signal. a phase difference measurement unit that measures the phase difference between the ranging tone signal from the rangefinding tone signal received from the separation filter and outputs the phase difference signal; and a phase difference measuring unit that outputs the sending control signal and the time difference signal A distance measuring device comprising: an arithmetic processing control section that calculates a distance to the target object from the phase difference signal.