JPS5839307B2 - Cotai Micro Hasouch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device equipped with a microwave oscillator and a microwave detection means, and in particular to a device that radiates microwaves into a predetermined space and moves an object that reflects the microwaves within this space. This invention relates to a device that detects changes in standing waves that occur when

Intrusion alarm devices using microwaves emit microwaves from a microwave oscillator through an antenna, and the degree of reflection varies depending on the presence or absence of an object within the detection area. ) to detect an intruder by mixing the waves to an intermediate frequency and detecting changes in the reflected waves.

Possible mixing methods in this case include installing a mixer diode inside the oscillator and placing the mixer diode directly on the antenna, but among these methods, placing the mixer diode directly on the antenna is difficult to manufacture. It's easy to do.

However, the biggest problem in adopting this method is the microwave coupling section to the mixing circuit.

Conventionally, a relatively complicated structure has been used as this microwave coupling section.

Therefore, the present invention provides a solid-state microwave device having a microwave coupling part that has a very simple structure, is easy to install, and allows sensitivity adjustment. explain.

In FIG. 1, 1 is a microwave oscillator and 2 is an electromagnetic horn antenna.

3 is a mixer diode support rod.

Reference numeral 4 denotes a metal tube, which has the structure shown in FIG. 2, and is fitted and connected to one electrode of the mixer diode 6.

Reference numeral 5 denotes a metal wire for forming a low frequency and DC closed circuit for the mixer diode 6, one end of which is connected to the metal cylinder 4, and the other end connected to the ground metal plate 7 and grounded.

Here, it is desirable to use a thin wire as the metal wire 5 in order to construct the low frequency and DC closed circuit.

This can reduce the influence on operation in a high frequency range.

8 is an insulator, and 9 is a ground metal terminal, which contacts the ground metal plate 7 and is electrically connected.

Although not shown in the figure, the ground metal plate 7 and the ground metal terminal 9 are insulated from the diode support rod 3 by an insulator.

10 is an insulator, and 11 is a detection metal terminal.

Numeral 12 is a nut for fixing the diode support rod 3.

FIG. 2 is an enlarged view of the mixer diode 6 and the metal tube 4. The metal tube 4 is cylindrical and has a notch 4', and the mixer diode 6 is fitted therein.

Now, as a function of this mixing section, a part of the radiation wave from the oscillator 1 and a reflected wave radiated from the horn antenna 2 and reflected by an external object are induced in the metal tube 4,
They are mixed by the mixer diode 6, and an intermediate frequency is generated between the ground metal plate 7 and the mixer diode support rod 3 through the metal wire 5.

By processing this intermediate frequency using a separately provided electronic circuit, the presence or absence of an object or its moving speed can be detected.

Although FIG. 1 shows a three-dimensional circuit antenna, the same applies to a planar antenna.

In the above configuration, the metal cylinder 4 has dimensions such that the outer diameter a =
It is configured to surround the mixer diode 6 with a length b = 5 myn.

The slit-shaped notch 4' provides elasticity.

Note that, if necessary, the metal tube 4 may be fitted onto the mixer diode 6 and further connected by soldering.

In this case, the frequency is 10.525GH, and the mixer detection output is 2 Ω resistor as a load, and the DC detection voltage is 100mV.
A metal plate as a detection target was placed 15 crrL away from the antenna 2, and the alternating current detection voltage obtained by moving the position of this metal plate by one wavelength was 100 mV.

The length of the metal tube 4 is selected so that the length of the part protruding from the antenna wall (metal tube 4 and mixer diode 6) is less than λ/4 and more than λ/8 (where λ is the wavelength). Without it, the sensitivity deteriorated.

That is, it is desirable that the height from the antenna wall surface to the top of the metal cylinder 4 is within the range of λ/8 to λ/4.

That is, outside the range, the detected voltage is 1/1o of the range.
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As described above, according to the device of the present invention, microwaves can be emitted into a predetermined space, the electric field strength formed thereby can be detected with high sensitivity, the sensitivity can be adjusted, and the device is simple in structure, easy to manufacture, and easy to assemble. It has good workability and is suitable as a small microwave search means.

[Brief explanation of drawings]

FIG. 1 is a structural cross-sectional view of an apparatus according to an embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of the main components thereof. 1...Microwave oscillator, 2...Horn antenna, 4...Metal tube, 5...
Metal wire, 6...Mixing diode.

Claims (1)

[Claims] 1. An oscillator having a solid-state microwave oscillation element, a horn antenna that radiates the output of the oscillator, a mixer diode attached to the opening of the horn antenna, and a metal fitted to one electrode of the mixer diode. a tube, and a thin metal wire that is connected at one end to the metal tube and grounded.The height from the wall surface of the horn antenna to the top of the metal tube is λ/8 to λ4 (where λ is microwave A solid-state microwave device characterized in that it has a wavelength range of .