CN1038349A - Microwave Moving Object Sensor - Google Patents

Abstract

The invention discloses a novel microwave moving target sensor. It is mainly composed of a waveguide slot antenna, a mixer, a high-frequency component combined with a body effect oscillator, a coded pulse modulator and a pseudo-correlation processor. The sensor has high sensitivity, good stability, strong anti-electromagnetic interference ability and simple structure. It can be widely used in anti-theft alarm, anti-collision of vehicles and ships, industrial control sensors, robot sensors and office automation equipment, etc.

Description

Moving-target microwave sensor

The present invention relates to a kind of moving-target microwave sensor, can be widely used as that industry control sensor, robot sensor, velometer, car and boat are crashproof, the probe in office automation equipment and the antitheft radar.

U.S. Pat P4117464 and USP3703718 and the disclosed moving-target microwave sensor of domestic patent CN8610543, polyphyly adopts electromagnetic horn and Medium Wave Guide antenna, use pulse modulated wave or continuous wave for transmitting, signal processor only adopts the doppler filtering amplifier.Because the electromagnetic horn beam area is subjected to certain restriction, and complex-shaped, processing is also inconvenient; Though the Medium Wave Guide antenna can be realized broad beam, be subject to the influence of environmental baseline; Transmitting of uniform pulse modulating wave or continuous wave scouted easily, is difficult to tackle active Electromagnetic Interference, thereby poor stability is installed on the burglar alarm, and false-alarm probability is also higher.

The purpose of this invention is to provide a kind of new type of microwave moving target sensor.It is simple in structure, and is highly sensitive, and anti-electromagnetic interference capability is strong, good stability.

The present invention is achieved through the following technical solutions:

The moving-target microwave sensor of design is made up of shell (9), Doppler high-frequency assembly, doppler filtering amplifier, spurious correlation processor, coded pulse modulator, video accumulation circuit and output relay.The waveguide leaky antenna (1) that Doppler high-frequency assembly is made by the high metal of conductance, frequency mixer (2), bulk-effect oscillator (3) are formed.They are brazed in the same waveguide.Its frequency mixer (2) and bulk-effect oscillator (3) place the two ends of waveguide respectively.The spurious correlation processor is made up of delay circuit, analog multiplier, gating circuit, shaping circuit.Spurious correlation processor, doppler filtering amplifier, video accumulation circuit, output relay are arranged on the same printed circuit board (4).Doppler high-frequency assembly and printed circuit board (4) are screwed on base plate (6).Panel open-width over against the crack is penetrated container, and edge PB-25 plastic foamboard (5).

Accompanying drawing 2 is functional-block diagrams of the antitheft radar of WL-4100.After energized, produce the pulse train coded signal by the coded pulse signal generator, give the microwave oscillation signal that modulator control bulk-effect oscillator (3) produces the coded pulse modulation, through waveguide leaky antenna (1) to the space quantity of radiation, in case run into the moving target invasion, to produce the echoed signal of an intrusion target, produce in frequency mixer (2) through waveguide leaky antenna (1) signal that receives and the portion of energy that transmits and clap the difference response, obtain Doppler frequency signal.Modulating pulse after the doppler filtering amplifier is sent into the analog multiplier of spurious correlation processor and passed through delay circuit is multiplied each other, and obtains the coded pulse sequence modulation envelope signal that includes moving target information.With its feed-in gating circuit and the next coded pulse signal discriminating gating of shaping circuit, select moving target signal again.Promote output relay work through video accumulation circuit, provide the relay contact make-and-break signal.Be transferred to alarm controller generation sound, the visual alarm of antitheft radar again by feeder line.Its reach is 7m * 12m or 4.5m * 60m, and can adjust according to on-the-spot needs.Antenna beam is selected in 10 ° of-150 ° of scopes as required.It can be under-20 ℃-+50 ℃ environmental baseline, and continous-stable work is more than 7 * 24 hours.

The present invention can accomplish broad beam owing to adopted the waveguide leaky antenna,, has overcome " dead band " effectively in indoor installation; Owing to adopted the pulse train modulating wave of spurious correlation processor and coding, has strong anti-electromagnetic interference (EMI) (noise FM interference, impulse disturbances, continuous wave interference, same asynchronous interference frequently) again.So signal is difficult for being scouted, false-alarm probability is low, and is highly sensitive, simple in structure, easy to process.

Fig. 1 is the moving-target microwave sensor structural representation.(1) be the waveguide leaky antenna, (2) are frequency mixer, and (3) are bulk-effect oscillator, and (4) are printed circuit board, and (5) are plastic foamboard, and (6) are base plate, and (7) are pad, and (8) are chock, and (9) are shell, and (10) penetrate window for the width of cloth.

Fig. 2 is the functional-block diagram of the antitheft radar of WL-4100.(11) be the coded pulse modulator, (12) are the spurious correlation processor.

Claims (1)

1. A microwave moving target sensor composed of Doppler high-frequency components, Doppler filter amplifiers, coded pulse modulators, signal processors, video accumulation circuits, and output relays is characterized by: A. The high-frequency component consists of a waveguide slot antenna [1], a mixer [2] and a body effect oscillator. The mixer [2] and the body effect oscillator [3] are brazed at both ends of the waveguide. B. The signal processor is a pseudo-correlation processor [12], which consists of a delay circuit, an analog multiplier, a shaping circuit, and a gating circuit. C. Pseudo-correlation processor [12], coded pulse modulator [11], Doppler filter amplifier, video accumulation circuit. Output relays are placed on the same printed board [4].

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