Abstract: A transmission unit emits an electromagnetic wave having the same frequency f as an output signal from a sending unit in a direction of a measurement axis. A detecting unit performs synchronous detection on a reflected wave detected by a directional coupler by an in-phase signal and a quadrature signal of the transmission signal, and by extracting DC component from the detection signal, detects the in-phase component and quadrature component of the reflected wave. An analysis signal generating unit mixes the in-phase component and quadrature component of the reflected wave and signals having periodicity corresponding to a prescribed distance, and using only one of the resulting side bands, generates an analysis signal. Fourier transform unit finds distance to the object of measurement from a profile obtained by Fourier transform of the analysis signal.

Abstract: A distance measuring method simultaneously measures a distance between a distance measurement system (10A) and a measurement object (M), and a relative speed therebetween. In the method, the distance measurement system sends an electromagnetic wave toward the measurement object as a traveling wave while changing a frequency thereof. The measurement object reflects the traveling wave to produce a reflected wave. The traveling wave and the reflected wave interfere with each other to produce a standing wave. The distance measurement system detects the amplitude of the standing wave and produces an amplitude signal representing the amplitude of the standing wave. Based on the produced amplitude signal, the distance measuring system derives the distance and the relative speed between the distance measurement system and the measurement object.

Abstract: A transmission unit emits an electromagnetic wave having the same frequency f as an output signal from a sending unit in a direction of a measurement axis. A detecting unit performs synchronous detection on a reflected wave detected by a directional coupler by an in-phase signal and a quadrature signal of the transmission signal, and by extracting DC component from the detection signal, detects the in-phase component and quadrature component of the reflected wave. An analysis signal generating unit mixes the in-phase component and quadrature component of the reflected wave and signals having periodicity corresponding to a prescribed distance, and using only one of the resulting side bands, generates an analysis signal. Fourier transform unit finds distance to the object of measurement from a profile obtained by Fourier transform of the analysis signal.

Abstract: A distance can be measured with high resolution. A frequency controller (7) controls a voltage control oscillator (2) so as to change a signal source frequency f in a range containing two center frequencies f1 and f2 and transmits it as a traveling wave from an antenna (4) to a target (5). A reflected wave reflected by the target (5) and the traveling wave interfere each other and form a standing wave. A power detector (6) detects power corresponding to the amplitude of the standing wave and performs Fourier transform based on the two center frequencies f1 and f2 in Fourier transform means (11, 12), respectively, thereby calculating radar image functions P1(x), P2(x). The distance d to the target (5) satisfies the conditions that the phase difference of the two radar image functions zero-crosses and the amplitude of the radar image functions becomes maximum. The zero cross point of the phase difference is a zero cross point of a linear function and can be identified with high resolution.

Abstract: A distance can be measured with high resolution. A frequency controller (7) controls a voltage control oscillator (2) so as to change a signal source frequency f in a range containing two center frequencies f1 and f2 and transmits it as a traveling wave from an antenna (4) to a target (5). A reflected wave reflected by the target (5) and the traveling wave interfere each other and form a standing wave. A power detector (6) detects power corresponding to the amplitude of the standing wave and performs Fourier transform based on the two center frequencies f1 and f2 in Fourier transform means (11, 12), respectively, thereby calculating radar image functions P1(x), P2(x). The distance d to the target (5) satisfies the conditions that the phase difference of the two radar image functions zero-crosses and the amplitude of the radar image functions becomes maximum. The zero cross point of the phase difference is a zero cross point of a linear function and can be identified with high resolution.

Abstract: A distance measuring method simultaneously measures a distance between a distance measurement system (10A) and a measurement object (M), and a relative speed therebetween. In the method, the distance measurement system sends an electromagnetic wave toward the measurement object as a traveling wave while changing a frequency thereof. The measurement object reflects the traveling wave to produce a reflected wave. The traveling wave and the reflected wave interfere with each other to produce a standing wave. The distance measurement system detects the amplitude of the standing wave and produces an amplitude signal representing the amplitude of the standing wave. Based on the produced amplitude signal, the distance measuring system derives the distance and the relative speed between the distance measurement system and the measurement object.

Abstract: A distance-measuring device for measuring the distance to an object (M) which comprises (i) a frequency-controlling means (11A) which outputs a frequency-control signal whose frequency is changing, (ii) a transmitting means (12A) which sends out an electromagnetic wave whose frequency is the same as the frequency of the frequency-control signal, (iii) a detecting means (13A) which is provided between the transmitting means (12A) and the object (M), detects the amplitude of a standing wave formed between the transmitting means (12A) and the object (M), and outputs an amplitude signal corresponding to the detected amplitude, and (iv) a signal-processing unit (14A) which forms a frequency-amplitude function representing the relation between the frequency of the frequency-control signal and the value of the amplitude signal and calculates the distance between the detecting means (13A) and the object (M) by using the period of the frequency-amplitude function.