JPS5828548B2 - Micro-Hatouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a microwave device having an oscillator that shares the transmission source of a transmitter and the local oscillation source of a receiver, which is used, for example, in a small radar device using a solid-state oscillation element (Gunn diode). It is something.

FIG. 1 shows a conventional microwave device in which one oscillator 1 serves as both a transmitter and a local oscillator.

In FIG. 1, during transmission, the FM oscillator 1 has a transmission frequency f
t, and the transmitted signal is sent to the antenna (not shown in Figure 1) through mixer 2. At this time, part of the transmitted power is coupled to the mixer diode of mixer 2, and the transmitted signal is sent to the antenna (not shown in Figure 1). Essentially giving a loss of transmit power.

During reception, the oscillator 1 oscillates at the local oscillation frequency fLo, and a portion thereof is coupled to the mixer diode of the mixer 2.

At this time, the received signals received by the antenna at the same time are sent to mixer 2.
mixer diode, where it is mixed with a local oscillator signal and converted to an intermediate frequency signal.

All received signals are also not coupled into the mixer diode, resulting in a loss of received power.

Additionally, since the local oscillation signal is not all coupled to the mixer diode, the remaining power is radiated into space by the antenna.

Therefore, there is at least 6 dB including the transmission power loss and the reception power loss, which is a system loss.

The radiation of the local oscillation signal was undesirable because it was the radiation of unnecessary waves.

This invention was made in view of the above points, and by connecting a transmitting/receiving oscillator, a transmitting/receiving antenna, and a switch circuit to one hybrid coupler, and further connecting a mixer directly to this switch circuit, system loss can be reduced. To provide a microwave device that generates less unnecessary radiation, has a simple structure, and can be finely adjusted.

Embodiments of the present invention are shown in FIGS. 2 and 3 and will be described in detail below.

In Figure 3, 10 is a hybrid coupler, 11.12
13 is a switch circuit, and 13 and 14 are diode mount devices as a mixer.

In FIG. 3, the same reference numerals as in FIG. 2 indicate the same or corresponding parts.

The oscillator 16 composed of a solid-state oscillation element oscillates at the transmission frequency, ft, at the time of transmission, and inputs the signal from the oscillator terminal 31 of the hybrid coupler 10 to the terminal 3 of the hybrid coupler 10.
334, and is distributed into two parts with a phase difference.

During transmission, the two TR switches 11 and 12 are driven by the TR switch driver circuit 19 and are in a short-circuited state.
The microwave power entering from the hybrid coupler 10 side is reflected, enters the hybrid coupler 10 again, is combined, exits from the antenna terminal 32 of the hybrid coupler 10, and is radiated from the transmitting/receiving antenna 16.

At the time of reception, the oscillator 15 oscillates at the local oscillation frequency fLO, which is divided into two by the hybrid coupler 10, passes through the TR switches 11 and 12, which are open at this time, and enters the diode mount devices 13 and 14, which are mixers. Supplied.

At the same time, the received signal received by the transmitting/receiving antenna 16 enters from the antenna terminal 32 of the hybrid coupler 10, is divided into two parts, passes through the TR switch 11.12, and is supplied to the diode mount device 13.14, which is a mixer, to generate a local oscillation signal. It is mixed with the intermediate frequency signal and becomes an intermediate frequency signal.

Intermediate frequency signals from two diode mount devices 13 and 14, which are mixers, are added together, amplified by an intermediate frequency amplifier 17, and output to an intermediate frequency output terminal 21.

The frequency control circuit 18 controls the oscillation frequency of the oscillator 15 so that it oscillates at the respective frequencies during transmission and reception.
controlled by

The frequency control circuit 18 and the TR switch driver circuit 19 are synchronized by a trigger generator 20 that controls repetition of transmission and reception.

In this way, one hybrid coupler 10 is used for both a balanced line transmission/reception switching device and a balanced mixer, and the circuit size is significantly larger than when using a normal balanced transmission/reception switching device and a balanced mixer. Simplified.

In terms of performance, the simplification does not result in any disadvantages.

Furthermore, as a simple radar, it has a simple structure, but compared to the conventional method shown in Fig. 1, which has a lot of system loss, it eliminates system loss and also has disadvantages such as radiation of local oscillation power. It's looking out.

As explained above, the present invention configures a microwave device in which a transmitting/receiving oscillator, a transmitting/receiving antenna, and a switch circuit are respectively connected to one hybrid coupler, and a mixer is directly connected to this switch circuit. System loss and unnecessary radiation are small, and the structure can be simplified. In particular, since the switch circuit and mixer are configured separately in this invention, each can be adjusted independently.

[Brief explanation of drawings]

FIG. 1 is a perspective configuration diagram of a conventional microwave device, and FIGS. 2 and 3 are a perspective configuration diagram and a program diagram for explaining a microwave device according to an embodiment of the present invention. Note that the same reference numerals in the figures indicate the same or equivalent parts. 10... High print coupler, 11.12... Switch circuit, 13.14... Diode mount device, 1
5... Oscillator, 16... Transmitting/receiving antenna.

Claims (1)

[Claims] 1. In a device that has an oscillator that shares the transmission source of the transmitter and the local oscillation source of the receiver, it is connected between the transmitting and receiving antenna and the oscillator, and transmits the output signal from the oscillator and the received signal from the transmitting and receiving antenna. a hybrid coupler that distributes the signals to a plurality of output terminals, synthesizes the signals from the respective output terminals, and outputs the signals to the transmitting/receiving antenna; a hybrid coupler that is connected to the output terminals of the hybrid coupler and combines the received signal and the local oscillation signal; The present invention is characterized by comprising a mixer that mixes the signal into an intermediate frequency signal, and a switch circuit that is connected between the hybrid coupler and the mixer and that is shortened during transmission and reflects the signal from the hybrid coupler. microwave equipment.