JPS6347376B2 - - Google Patents

Description

Detailed Description of the Invention (a) Technical Field of the Invention The present invention relates to a receiving local oscillator of an in-line mixer having two high frequency input terminals and an intermediate frequency terminal into which a receiving signal and the output of the receiving local oscillator are input separately. It is related to a wireless device that converts a received signal into an intermediate frequency signal using an in-line mixer equipped with a reactance element or waveformer on the side so that the received signal matches the mixer diode, and is inexpensive when sending a negotiation or control signal to the other station. This invention relates to a two-way communication system that can be configured as follows.

(b) Prior Art and Problems FIG. 1 is a block diagram of a circuit of a conventional two-way communication wireless device that uses an in-line mixer and transmits a negotiation or control signal to a partner station.

In the figure, 1 is the antenna, 2 is the circulator, 3 is the modulator, 4 is the isolator, 5 is the reception local oscillator, fl is the frequency of the reception local oscillator, and fl' is the frequency fl of the reception local oscillator by negotiation or control signal. Modulated frequency, 6 is inline mixer, 7
indicates a reactance element or wave device.

The conventional circuit shown in FIG. 1 was developed by the applicant in 1957.
The two wireless devices for which the patent application was filed on April 21 can be configured at low cost when sending meeting or control signals from the receiving side. The in-line mixer 6, for example, has two openings on the same axis on a straight line of a waveguide, and has one mixer diode inside the waveguide, and allows signals input from the two openings to be mixed. The signals are mixed by a diode and then passed through a low frequency circuit to obtain an intermediate frequency signal. This inline mixer 6
A reactance element or wave generator 7 is provided on the side where the output of the receiving local oscillator 5 is input through the isolator 4 so that the received signal is matched to the diode. In this way, the signal of frequency fl from the reception local oscillator 5 leaks to the input side of the reception signal, and inputs it to the modulator 3 via the circulator 2, and modulates it during oscillation using a negotiation or control signal. circulator 2 as a signal with frequency fl'
and transmitting via antenna 1. Although bidirectional communication is achieved in this way and the configuration is inexpensive, it still requires the circulator 2 and modulator 3, which is expensive.

(c) Object of the Invention The object of the present invention is to eliminate the above-mentioned drawbacks and to provide a two-way communication system capable of transmitting a meeting or control signal to a partner station with an extremely low-cost configuration.

(d) Structure of the Invention In order to achieve the above object, the present invention provides an in-line mixer having two high frequency input terminals and an intermediate frequency terminal into which a received signal and the output of a receiving local oscillator are separately input. In a wireless device that uses the received signal as an intermediate frequency, an in-line mixer is provided with a reactance element or a waveform generator so that the received signal matches the mixer diode on the oscillator side, and a DC bias current is passed through the mixer diode. The output of the receiving local oscillator of the in-line mixer that leaks to the received signal side changes almost linearly with respect to a logarithmic change in the current value, and the received signal of the in-line mixer is adjusted to an intermediate frequency. By superimposing a meeting or control signal on the DC bias current, the output leaking to the receiving signal side of the receiving local oscillator in addition to the mixer diode is amplitude modulated. It is characterized by sending an amplitude modulated signal to the other station.

(e) Embodiment of the invention An embodiment of the invention will be described below with reference to the drawings. FIG. 2 is a block diagram of a circuit of a two-way communication type wireless device that uses an in-line mixer according to an embodiment of the present invention and transmits a meeting or control signal to a partner station, and FIG. 3 shows the in-line mixer of FIG. This is an example of a characteristic diagram showing changes in modulation loss and power leaked from the output of the receiving local oscillator to the antenna side when a DC bias current is applied to the mixer diode in the antenna and this current is varied logarithmically.

Components in the figure that have the same functions as those in FIG. 1 are indicated by the same symbols. 6' is an in-line mixer, 8 is an intermediate frequency amplifier, L is an inductance, and _C1 is a capacitor, and this combination constitutes a low frequency amplifier. R
indicates a resistor, and C ₂ indicates a capacitor that cuts direct current.

In FIG. 2, a DC bias current is passed through the mixer diode in the in-line mixer 6', and this current is varied logarithmically to convert the received signal of the mixer diode into an intermediate frequency signal. When measuring the power PL' leaked to the antenna 1 side of the signal input to the in-line mixer 6' via the reactance element or wave generator 7, the DC bias current is around 2.0 mA to 4.0 mA, as shown in the example in Fig. 3. As can be seen, the change in conversion loss is small in this vicinity, and the change in power leaking to the antenna 1 side is almost linear.
Utilizing this characteristic, a bias current of approximately 3 mA is caused to flow, and when a control signal is added superimposed on this bias current, the in-line mixer 6 The signal input to ' is modulated in amplitude and has a frequency fl''(fl'' = fl±fc, where fl is the frequency of the receiving local oscillator, and fc is the frequency of the negotiation or control signal), and the signal leaks to the antenna 1 side. It turns out. Also, the change in conversion loss when converting the received signal at frequency fr to an intermediate frequency at frequency fl of the receiving local oscillator 5 using a mixer diode is very small, so if you suppress the amplitude change with a limiter etc. There is no amplitude modulation effect.

The above points are utilized in the circuit shown in FIG. 2 of the present invention, in which the DC bias current is supplied to the mixer diode via the resistor R and the inductance L.
(Taking FIG. 3 as an example, 3 mA) The meeting or control signal is superimposed on the DC bias current and applied to the mixer diode via a low-pass filter consisting of an inductance L and a capacitor _C1 . Further, the received signal of frequency fr is converted into an intermediate frequency signal at the frequency of the receiving local oscillator 5, and the signal is amplified by an intermediate frequency amplifier 8 (also provided in the conventional example) via a capacitor _C2 . Width and receive. In this way, even if the circulator 2 and modulator 3 of the circuit shown in FIG. Therefore, a negotiation or control signal can be transmitted to the other station in an extremely inexpensive manner.

(f) Effects of the Invention As described in detail above, the present invention has the effect of providing a two-way communication system that can transmit meeting or control signals to the other station with an extremely low-cost configuration.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a circuit of a conventional two-way communication wireless device that transmits a meeting or control signal to a partner station, and FIG. Figure 3 is a block diagram of the circuit of a transmitting two-way communication wireless device. Figure 3 shows the conversion loss and reception local when a DC bias current is passed through the mixer diode in the in-line mixer in Figure 2 and this current is varied logarithmically. It is an example of a characteristic diagram showing changes in power leaked from the output of the oscillator to the antenna side. In the figure, 1 is an antenna, 2 is a circulator, 3 is a modulator, 4 is an isolator, 5 is a receiving local oscillator, 6 and 6' are in-line mixers, 7 is a reactance element or waveformer, 8 is an amplifier, and L is an inductance. , C ₁ and C ₂ are capacitors, and R is a resistance.

Claims (1)

[Claims] 1. A reactance element or a reactance element is installed on the receiving local oscillator side of an in-line mixer that has two high-frequency input terminals and an intermediate frequency terminal into which the receiving signal and the output of the receiving local oscillator are input separately so that the receiving signal matches the mixer diode. In a wireless device that converts the received signal into an intermediate frequency signal using an in-line mixer equipped with a frequency converter, a DC bias current is passed through the mixer diode, and this current value is applied to the in-line mixer according to a logarithmic change in the current value. The output of the receiving local oscillator that leaks to the received signal side changes almost linearly, and the conversion loss of the in-line mixer that converts the received signal into an intermediate frequency signal has a small fluctuation value, and the meeting or control signal is superimposed on the DC bias current, amplitude-modulated the output leaking to the receiving signal side of the receiving local oscillator in addition to the mixer diode, and transmitting the amplitude-modulated signal to the opposite station. Direct communication method.