JPS58146142A - Transmitter and receiver - Google Patents

Abstract

PURPOSE:To improve the quality of transmission, by modulating a main carrier and transmitting it with a signal modulating a subcarrier with the signal input at the transmission side, in a transmitter and receiver using a part of a transmission output signal as a reception local oscillation signal. CONSTITUTION:In a submodulator 14, a subcarrier f1 is modulated with an input signal 1, a millimeter wave is modulated with an output of the submodulator 14 and transmitted from an antenna 6. Electromagnetic waves (f2 in subcarrier) from a remote station received at the antenna 6 frequency-modulate the output of the main modulator as a local oscillation signal and are demodulated at a demodulator 9. The output of the demodulator 9 passes through a filter 15 eliminating the subcarrier wave f1 and is demodulated at the demodulator 16.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high frequency transmitting/receiving device, and particularly to a transmitting/receiving device suitable for communication at an extremely high frequency such as a millimeter wave band.

For communication using a transmitting and receiving device in a high frequency band such as the millimeter wave band, a frequency converter and two oscillators are used in the transmitting and receiving device.

Millimeter wave band devices such as amplifiers are extremely expensive.

Furthermore, the millimeter wave band suffers from large rainfall attenuation, so the section distance cannot be long, so the cost per channel is higher than that of microwave band communication. Therefore, millimeter wave band transmitting/receiving devices are designed to simplify the circuit configuration, especially the circuit configuration of millimeter wave band devices, compared to microwave band transmitting/receiving devices. One of them is a circuit configuration in which a part of the transmission output signal is branched and used as a receiving station oscillator signal, and the receiving local oscillator is omitted. However, in a configuration where a part of the transmission output signal is simply branched and used as the reception station oscillation signal, the transmission output signal is modulated by the modulation signal, so the transmission modulation signal is output as the reception demodulation output. Therefore, it becomes a noise component with respect to the normal demodulated output signal. Therefore, communication is impossible in this state.

Therefore, in conventional transmitting/receiving devices of this type.

A part of the modulated signal for transmission is branched to make the two phases opposite to each other, and the amplitudes are made equal and applied to the demodulated output for reception.

It was common practice to cancel the modulated signal as a noise component. However, in such conventional devices, the modulation sensitivity of the transmitting modulator, the demodulation sensitivity of the receiving demodulator, the gain of the amplifier of the modulated signal system, etc. cannot be canceled out due to temperature changes or changes over time. The modulated signal component comes out and becomes a noise component with respect to the normal demodulated output signal, degrading the quality of the transmitted signal. By the way, this deterioration in transmission signal quality can be almost prevented by applying feedback, but this is extremely expensive when the frequency is high.
From the standpoint of prioritizing price as mentioned earlier.

The above-mentioned cancellation type transmitter/receiver is used.

Therefore, an object of the present invention is to provide a transmitting/receiving device that shares a part of the transmitting output signal as a receiving station signal, in which the modulated signal of the transmitting that appears in the demodulated output of the receiving can be removed even if it is subject to temperature changes or changes over time. Another object of the present invention is to provide a transmitting/receiving device that can be realized at a low cost.

According to the present invention, there is provided a transmitting/receiving device having a means for sharing a part of the transmitted output signal as a receiving station oscillation signal, the sub-modulator modulating the transmitting side with a modulation signal, and the output signal of the sub-modulator. A main modulator that emits a transmission output signal is provided, and a part of the transmission output signal generated by the main modulator is used as a signal from the receiving station on the receiving side to transmit the transmission output signal from the opposing transmitting/receiving device. a main demodulator that demodulates the two-frequency converted signal; a P-wave device that removes the carrier frequency component of the sub-modulator that appears in the output of the main demodulator; and a signal that has passed through the P-wave device. A transmitter/receiver is provided with a flank modulator for demodulating the signal, and the carrier wave frequency of the sub-modulator is set to be different from the carrier wave frequency of the corresponding sub-modulator of the opposing transmitter/receiver. It will be done.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing an example of the configuration of a conventional transmitting/receiving apparatus that shares a part of a transmitted output signal as a receiving station signal. In FIG. 1, a modulation signal is applied to signal input terminal 1,
After splitting a part of the modulated signal by splitter 2, it is split into millimeter wave band FM.
Apply modulation to modulator 3. The output of the millimeter-wave band jump modulator 3 passes through a circulator 4 for both transmission and reception, a part of which is reflected in an impedance adjustment circuit 5, and the other part is sent out from an antenna 6 as a transmission output. On the other hand, the reception input received by the antenna 6 is guided via the impedance adjustment circuit 5 and the circulator 4 to the reception frequency converter 7 together with a part of the transmission output reflected by the impedance adjustment circuit 5, and a part of the transmission output is The frequency is converted to an intermediate frequency as a signal emanating from the receiving station. Next, the intermediate frequency signal is amplified by an amplifier 8 and then demodulated by an FM demodulator 9. Of course, this demodulated output includes the modulated signal of the transmitter on the other end, but since a part of the transmitting output of the local station is used as the receiving station signal, the modulated signal of the local station is also demodulated. be done.

By the way, the modulated signal of the transmission branched by the splitter 2 described above is amplified by the amplifier 10 to the same level as the modulated signal of the same transmission, which is included in the demodulated output, and is also amplified by the phase shifter 11 to the combiner 12. The phases are matched so that they are synthesized in completely opposite phases. Therefore, the modulated signal of the own station included in the demodulated output is canceled, and only the modulated signal of the other station, that is, the normal demodulated signal, can be taken out from the signal output terminal 13. However, as mentioned above, in this case, if the modulation sensitivity of the millimeter-wave FM modulator 3 and the demodulation sensitivity of the FM demodulator 9 change due to environmental conditions such as temperature, a level difference will occur between the modulated signals to be canceled. Complete cancellation is no longer possible, and the modulated signal of the own station appears as a noise component. this is,
The same holds true even if the phase characteristics of the gain 9 phase shifter 11 of the amplifier 10 change.

It was deteriorating the transmission quality. However, in spite of this, a millimeter wave band transmitting/receiving device still has a receiving local section.

FIG. 2 is a diagram showing the configuration of an embodiment of a transmitting/receiving apparatus according to the present invention, which shares a part of the transmitted output signal as a receiving station signal. In FIG. 2, parts corresponding to those in FIG. 1 are designated by the same reference numerals. A modulation signal is applied to the signal input terminal 1, and modulation is applied to the FM modulator whose carrier frequency 11 is about 10 MHz or less, that is, the sub-modulator 14 described earlier,
The output signal of this sub-modulator 14 is used by the millimeter wave band FM modulator 3 (
Modulation is applied to the main modulator (equivalent to the main modulator explained earlier). That is, 2
Transmit with heavy modulation. The output of the millimeter wave band FM modulator 3 passes through a circulator 4 which is used for both transmission and reception, a part of the output is reflected in an impedance adjustment circuit 5, and most of the other part is sent out from an antenna 6 as a transmission output. The reception input received by the antenna 6 is the impedance adjustment circuit 5.
．． Impedance adjustment circuit 5 via circulator 4
The receiving frequency converter 7 together with a part of the transmitted power reflected by
A part of the transmitted output is frequency-converted to an intermediate frequency as a receiving station oscillation signal. After the intermediate frequency signal is amplified by an amplifier 8, it is demodulated by an FM demodulator 9, which is a main demodulator.

On the other hand, the carrier frequency of the sub-modulator (equivalent to 14) of the transmitter of the other station is set to f2, which is slightly different from f+.

Therefore, the output of the FM demodulator 9 of the own transmitting/receiving station mentioned above is FM
Two output signals with modulated carrier frequencies f and f2 are obtained.

FIG. 3 is a diagram showing the form of the output signal of the FM demodulator 9, and the output signal 17 having a frequency of f is unnecessary because it is a carrier wave modulated by the modulation signal of the own station. Therefore, only the output signal 18 with a frequency of 12 is transmitted to the band p-wave filter 1.
5 is selected, and demodulated again by an FM demodulator with a carrier frequency of 12, that is, a flank modulator 16, and a regular demodulated signal is taken out from the signal output terminal 13. In this way, the unnecessary modulated signal of the own station is transmitted to the bandpass filter 15 in the state of carrier frequency f+.
Therefore, there is no problem of deterioration of transmission signal quality due to changes in environmental conditions, etc.

Note that the sub-modulator 14° band p-wave amplifier 15 and side modulator 16 newly required in the present invention have low frequencies, so in terms of price, they can be replaced with the conventionally required divider 2° amplifier 119 phase shifter. This is almost the same as the 119 combiner 12.

In the above embodiment, an impedance adjustment circuit 5 is provided as a means for sharing the transmission output as a receiving station signal, and the impedance adjustment circuit 5 is reflected here and guided to the frequency converter 7.
This is done by using some means to convert a part of the transmitted output to the frequency converter 7.
For example, the signal may be branched directly from the millimeter wave band FM modulator 3 and supplied, or a directional coupler or the like may be inserted on the output side and the signal may be branched and supplied. Furthermore, although the embodiments have been described using the millimeter wave band, the present invention is not limited to the millimeter wave band. Furthermore, in the explanation of the embodiment, the case of a direct modulation method was explained, but it can also be applied to a hetero gain method such as using a 70 MI (z-band FM modulator) as the FM modulator 3 which is the main modulator. In other words, the frequency is not limited.Furthermore, although the case of FM modulation is explained as a modulation method, it can also be applied to AM modulation and PM modulation without any problem.Note that this transmitting/receiving device is a sub-modulator. Therefore, it is unavoidable that the channel capacity of the device is smaller than that of a device that does not use this.

As is clear from the above explanation, according to the present invention,
In a transmitting/receiving device that shares a part of the transmitted output signal as a receiving station oscillation signal, in addition to the main modulator and main demodulator, a sub modulator, flank modulator, and band tear wave modulator are provided, and the sub modulator By setting the frequency of the carrier wave differently in the opposing transmitter/receiver, the unnecessary carrier wave of the sub-modulator of the local station that appears in the output of the main demodulator is removed by the lachrymal organ, thereby achieving stable transmission quality. Good communication becomes possible.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of the configuration of a conventional transmitting/receiving device that shares a part of a transmission output signal as a receiving station signal; FIG. 2 is a diagram showing the configuration of an embodiment of a transmitting/receiving device according to the present invention; FIG. 3 shows the shape of the output signal of the FM demodulator in the device according to the invention shown in FIG. Explanation of symbols: 2 is a distributor, 3 is a millimeter wave band FM modulator (main modulator), 4 is a circulator, 5 is an impedance adjustment circuit, 6 is an antenna, 7 is a receiving frequency converter, 8 is an amplifier, 9 is an FM demodulator (main demodulator), 10 is an amplifier, 1
1 is a phase shifter, 12 is a synthesizer, 14 is an FM modulator (sub modulator), 15 is a band F-wave device, and 16 is an FM demodulator (flank modulator). Hayabusa 1 Figure 2 Figure f Figure 3

Claims (1)

[Scope of Claims] 1. A transmitting/receiving device having means for sharing a part of the transmitted output signal as a receiving station signal, comprising: a sub-modulator that modulates the transmitting side with a modulation signal; A main modulator that modulates the output signal and generates a transmission output signal is provided, and a part of the transmission output signal emitted by the main modulator is provided on the receiving side as a transmission output signal from the receiving station as the transmission output from the opposing transmitting/receiving device. 9. a main demodulator for demodulating the frequency-converted signal; a p-wave filter for removing a carrier frequency component of the sub-modulator appearing in the output of the main demodulator; and a filter. and a flank modulator that demodulates the transmitted signal.
The transmitting/receiving device is configured such that the carrier wave frequency of the sub-modulator is different from the carrier wave frequency of the corresponding sub-modulator of the opposing transmitting/receiving device. Remaining days below