JP4486608B2 - Microwave band radio transmitter, microwave band radio receiver and microwave band radio transceiver system - Google Patents

Description

  The present invention relates to a microwave band radio transmission apparatus, a microwave band radio reception apparatus, and a microwave band radio transmission / reception system, and more particularly, to a microwave band radio transmission apparatus and a microwave that wirelessly transmit a plurality of broadcast waves in the microwave band. The present invention relates to a band wireless receiver and a microwave band wireless transmission / reception system.

  Conventionally, as a microwave band wireless transmission system, a microwave band wireless transmission apparatus that wirelessly transmits two systems of TV signals, and a microwave that receives two systems of TV signals wirelessly transmitted from the microwave band wireless transmission apparatus. There is one provided with a band wireless receiver (for example, see Japanese Patent Application Laid-Open No. 2004-328331 (Patent Document 1)). Here, the microwave band refers to a frequency band including a millimeter wave band.

  A block diagram of such a microwave band wireless transmission system is shown in FIG. This microwave band wireless transmission system includes a microwave band wireless transmission device 9-3 and a microwave band wireless reception device 10-3, and two types of broadcasts, a first satellite broadcast wave and a second satellite broadcast wave. The microwaves are simultaneously received by the microwave band wireless transmission device 9-3 and wirelessly transmitted to the microwave band wireless reception device 10-3. 8A shows the frequency arrangement in the radio frequency band of the microwave band radio transmission / reception system, and FIG. 8B shows the frequency spectrum of the output on the reception side of the microwave band radio transmission / reception system.

  First, in the microwave radio transmitting apparatus 9-3, the first modulation signal 5a from the first satellite broadcast receiving antenna 1a and the second modulation signal received from the second satellite broadcast receiving antenna 1b. The signal (intermediate frequency signal) 5b is input to the reference signal addition circuits 2a and 2b.

  The reference signal adding circuit 2a includes a variable amplifier 203a, a frequency mixer 201a, and a power combiner 202a, and the reference signal adding circuit 2b includes a variable amplifier 203b, a frequency mixer 201b, and a power combiner 202b. In the reference signal addition circuits 2a and 2b, the frequency converters 201a and 201b use the reference signal source 2c as a local oscillator, and the first and second modulation signals 5a and 5b are frequency-converted to the second intermediate frequency multiplexed signals 71a and 71b. Convert (up-convert). At this time, the power combiners 202a and 202b simultaneously add the reference signal from the reference signal source 2c to generate second intermediate frequency multiplexed signals 71a and 71b, which are input to the frequency conversion / transmission circuits 3a and 3b.

  Here, the signal from the local oscillator 7 is supplied to the frequency conversion circuits 3a and 3b, and the second intermediate frequency multiplexed signals 71a and 71b are up-converted to a millimeter wave band to generate radio multiplexed signals 72a and 72b. The

  The frequency conversion circuit 3a includes a frequency mixer 301a, a filter 302a, and a transmission amplifier 303a. The frequency conversion circuit 3b includes a frequency mixer 301b, a filter 302b, and a transmission amplifier 303b. Radio multiplexed signals 72a and 72b are amplified by transmission amplifiers 301a and 301b, respectively. The radio multiplexed signal 72a amplified by the transmission amplifier 301a is transmitted from the vertically polarized transmission antenna 4a that generates vertical polarization, and the radio multiplexed signal 72b amplified by the transmission amplifier 301b is horizontally polarized. Is transmitted from the horizontally polarized transmission antenna 4b. Here, the vertically polarized radio multiplexed signal 72a is composed of a radio reference signal 771a and a radio modulated signal 772a, while the horizontally polarized radio multiplexed signal 72b is composed of a radio reference signal 771b and a radio modulated signal 772b. ing.

  On the other hand, on the microwave band radio receiving apparatus 10-3 side, the vertically polarized radio multiplexed signal 72a is received by the vertical polarization receiving antenna 14a, while the horizontally polarized radio multiplexed signal 72b is used for horizontal polarization. The radio multiplexed signals 72a and 72b received by the receiving antenna 14b are input to the frequency conversion circuits 12c and 12d. In the frequency conversion circuits 12c and 12d, the received radio multiplexed signals 72a and 72b are once amplified by the amplifiers 110a and 110b, and the image signals for the local oscillator 7 on the transmission side are removed by the bandpass filters 111a and 111b. The

  Thereafter, in the frequency conversion circuit 12c, the frequency modulation 122a is frequency-converted (multiplied) based on the radio reference signal 771a that is a sine wave signal by the frequency mixer 122a, and an input signal on the transmission side of the frequency fIF1a is generated. The In this microwave band wireless transmission system, the first modulated signal 5a of the first satellite broadcast is reproduced. Further, unnecessary waves generated in the frequency conversion process by the frequency mixer 122a are suppressed by the filter 77a. Then, the first modulated signal 5a in which the unnecessary wave is suppressed is amplified by the amplifier 76a, and then output as the output signal 75a from the output terminal 15a.

  Similarly, in the frequency conversion path 12d, the frequency mixer 122b converts (multiplies) the radio modulation signal 772b by the radio reference signal 771b, which is a sine wave signal, and generates an input signal on the transmission side of the frequency fIF1b. . In this microwave band radio transmission system, the second satellite broadcast wave signal 5b is reproduced. Further, here, unnecessary waves generated in the frequency conversion process by the frequency mixer 122b are suppressed by the filter 77b. Then, the first modulated signal 5b in which the unnecessary wave is suppressed is amplified by the amplifier 7b and then output as the output signal 75b from the output terminal 15b.

  The output signals 75a and 75b output from the output terminals 15a and 15b are connected to the satellite broadcast tuner 30 via the signal switch 31.

  By the way, the microwave band wireless transmission system has the following problems.

  In the microwave radio transmission apparatus 9-3, since the frequency of the radio reference signal is equal in horizontal and vertical polarization, the first and second modulation signals 5a and 5b input on the transmission side are completely different frequencies. In the case of the band, no major problem occurs. However, in the case of the first modulated signal of the first satellite broadcast and the second modulated signal of the second satellite broadcast, it is input to the microwave band radio transmitter 9-3. The first and second modulated signals (frequency fIF1a, fIF1b) are substantially equal in frequency band. At this time, since the radio reference signal itself has the same frequency for one wave for both horizontally and vertically polarized signals, the radio signal that is the transmission signal (originally the modulation signal input to the microwave radio transmitter 9-3) is Since the antenna cross polarization component is incomplete, the main polarization component becomes a leakage component, and the leakage component is frequency down-converted by the microwave radio receiver 10-3 and falls into the equivalent frequency bands fIF1b and fIF1a to cause interference. It was the cause.

  Therefore, the circuit configuration of the microwave band radio transmission device 9-3 and the microwave band radio reception device 10-3 is a two-line parallel circuit configuration (the transmission side is 5a, 5b which is an input unit to 4a which is an output unit). 4b, the receiving side is 14a and 14b which are the input units, and 15a and 15b which are the output units, and although the same parts are used and the circuit configuration is the same, the first and second of both systems It was difficult to equalize the bandwidths of the two modulation signals.

  For example, the first modulation signal 5a on the transmission side—the output signal 75a on the reception side has a frequency bandwidth of 300 MHz to 1000 MHz, and the second modulation signal 5b on the transmission side—the frequency bandwidth of the output signal 75b on the reception side. Is 1000 MHz to 2500 MHz, and signals handled by both systems have different frequency bandwidths. That is, if the first modulation signal 5a on the transmission side and the output signal 15a on the reception side are simultaneously set to a frequency bandwidth of 1000 MHz to 2500 MHz, the above-described interference is likely to occur.

In order to reduce the influence of such interference, it is necessary to sufficiently ensure the cross polarization characteristics of the antenna and to make the two input modulation signal power levels on the transmission side substantially equal. For this reason, strict control is required for the antenna placement and arrangement in order to strictly control the input modulation signal level to the microwave radio transmission apparatus and to secure the cross polarization characteristics of the antenna.
JP 2004-328331 A

  Accordingly, an object of the present invention is to provide a microwave band wireless transmission apparatus and a microwave band that can easily realize good transmission characteristics with less interference even when two modulated signals wirelessly transmitted in the microwave band are in the same frequency band. An object of the present invention is to provide a radio receiver and a microwave band radio transmission / reception system.

In order to solve the above problem, a microwave band wireless transmission device of the present invention is
A first transmission-side frequency converter that up-converts the frequency of the input first modulated signal into a microwave band;
A second transmission-side frequency converter that frequency-converts the input second modulated signal into a microwave band;
A first reference signal adding unit that adds a first reference signal to the first modulated signal that is frequency up-converted to a microwave band by the first transmission-side frequency conversion unit;
Second reference signal addition for adding a second reference signal having a frequency different from that of the first reference signal to the second modulated signal frequency-converted to the microwave band by the second transmission side frequency converter And
The first radio multiplexing in which the first reference signal is added by the first reference signal adding unit to the first modulated signal whose frequency is up-converted to the microwave band by the first transmitting frequency converter. The second reference signal adding unit adds the second reference signal to the second modulation signal that is frequency up-converted to the microwave band by the first transmission unit that transmits the signal and the second transmission side frequency conversion unit. And a second transmitter that transmits the second radio multiplexed signal to which the signal is added with a polarization different from that of the first radio multiplexed signal.

  According to the microwave radio transmitting apparatus having the above-described configuration, even if the input first and second modulated signals are in the same frequency band, the first radio reference in the limited radio frequency band is set on the transmission side. Since the frequencies of the signal and the second radio reference signal are different, the first and second modulated signals can be frequency up-converted using the first and second reference signals on the receiving side. For this reason, the first and second modulated signals can be independently frequency-converted and a reference signal can be added, and a radio reference signal having one frequency which is a leakage component from each of the first and second transmitters. Can improve interference / interference characteristics by performing frequency conversion to different frequency bands. As a result, the independence between the first and second modulated signals can be enhanced. Therefore, even if two modulated signals transmitted wirelessly in the microwave band are in the same frequency band, good transmission characteristics with less interference can be easily realized.

Moreover, in the microwave radio transmission apparatus of one embodiment,
A frequency divider is provided that frequency-divides one of the first reference signal and the second reference signal to generate the other of the first reference signal and the second reference signal.

  According to the microwave band wireless transmission device of the above embodiment, one of the first reference signal and the second reference signal is frequency-divided, whereby the other of the first reference signal and the second reference signal is obtained. By generating, only one reference signal source is required, and frequency control is remarkably facilitated. Further, in each circuit, there is no influence of interference or interference caused by a plurality of oscillation sources. In addition, the microwave band wireless transmission device can be further simplified and the cost can be reduced.

Moreover, in the microwave radio transmission apparatus of one embodiment,
The first transmission-side frequency conversion unit up-converts the frequency of the first modulated signal so as to be in a lower sideband with respect to the first reference signal,
The second transmission side frequency conversion unit up-converts the frequency of the second modulated signal so as to be in the upper side band with respect to the second reference signal.

  According to the microwave band wireless transmission device of the above embodiment, even if two input modulation signals are in the same frequency band, the first modulation signal has a frequency in the microwave band as a lower side band modulation signal. The up-converted second modulated signal is frequency up-converted to the microwave band as an upper side band modulated signal, and the first reference signal is converted to the lower side band modulated signal by the respective frequency conversion. In addition, a second reference signal is added to the modulation signal in the upper sideband. As a result, the first radio multiplexed signal and the second radio multiplexed signal are configured, and the first and second reference signals are arranged at the upper limit and the lower limit of the frequency on the radio frequency axis. Therefore, the frequency interval becomes the largest, and when the receiving side performs frequency conversion using the first and second reference signals, the leaky wave component greatly differs in the demodulated modulation signal frequency band. The interference / interference characteristics can be further improved, and as a result, the independence between the respective modulation signals can be further increased.

Moreover, in the microwave radio transmission apparatus of one embodiment,
The first transmission-side frequency converter is
A first transmission-side intermediate frequency converter that upconverts the first modulated signal to an intermediate frequency band;
A first transmission-side microwave frequency conversion unit that frequency-converts the first modulation signal frequency up-converted to an intermediate frequency band by the first transmission-side intermediate frequency conversion unit into a microwave band;
The second transmission-side frequency converter is
A second transmission-side intermediate frequency converter that up-converts the second modulated signal to an intermediate frequency band;
A second transmission-side microwave frequency conversion unit that frequency-converts the second modulated signal frequency-converted to the intermediate frequency band by the second transmission-side intermediate frequency conversion unit into a microwave band;
The first reference signal adding unit adds the first reference signal to the first modulated signal frequency up-converted to an intermediate frequency band by the first transmitting intermediate frequency converting unit,
The second reference signal adding unit adds the second reference signal to the second modulated signal frequency-converted to the intermediate frequency band by the second transmitting intermediate frequency converting unit.

  According to the microwave radio transmission apparatus of the above embodiment, the first reference signal and the first modulated signal frequency-converted by the first transmission intermediate frequency conversion unit and the first reference signal adding unit are used. The first intermediate frequency multiplexed signal is generated. Further, the second transmission intermediate frequency conversion unit and the second reference signal addition unit generate a second intermediate frequency multiplexed signal composed of the second reference signal and the second modulated signal frequency-converted. The first intermediate frequency multiplexed signal is frequency upconverted to a microwave band by the first transmission side microwave frequency converter, and the second intermediate frequency multiplexed signal is converted to the second transmission side microwave. The frequency is converted up to the microwave band by the frequency converter. Thereby, in the frequency conversion to the radio frequency, a harmonic mixer such as an even harmonic mixer can be used, and the local oscillation frequency is set to, for example, 27 GHz to 30 GHz which is approximately half the frequency of the radio signal. Therefore, it is not necessary to directly oscillate at the local oscillation frequency of 60 GHz band, and the configuration of the local oscillator becomes easy. In addition, since the power ratio between the modulation signal and the reference signal in the multiplexed signal can be controlled by the intermediate frequency stage having a low frequency, it is easy to control the ratio in the radio frequency band to be constant.

Moreover, in the microwave radio transmission apparatus of one embodiment,
A frequency multiplier that generates a local oscillation signal by frequency multiplying at least one of the first reference signal or the second reference signal;
The first and second transmitting microwave frequency converters perform frequency up-conversion based on the local oscillation signal generated by the frequency multiplier.

  According to the microwave band wireless transmission device of the above embodiment, two local oscillators are required for the two first and second transmission-side microwave frequency converters for generating radio signals of both polarizations. In this embodiment, it is necessary to control the oscillation frequency and the oscillation power by exciting two frequency multipliers with either the first reference signal or the second reference signal. , Generate a local oscillation signal. Therefore, the two local oscillation frequencies are the same, and it is not necessary to generate the two oscillation frequencies. As a result, the local oscillation frequency can be easily configured, and the frequency control can be controlled by the reference signal in the low frequency band, so that a stable wireless transmission device can be configured.

In the microwave band radio receiver of the present invention,
A microwave band radio receiving apparatus that receives first and second radio multiplexed signals transmitted from the transmitting side with different polarizations, respectively,
The first radio multiplexed signal is composed of a first radio modulation signal and a first radio reference signal arranged in a frequency band above the first radio modulation signal,
The second radio multiplexed signal is composed of a second radio modulation signal and a second radio reference signal arranged in a frequency band lower than the second radio modulation signal,
A first receiver for receiving the first radio multiplexed signal;
A second receiver for receiving the second radio multiplexed signal;
A first filter for suppressing a leakage component of the second radio reference signal included in the first radio multiplexed signal received by the first receiver;
A second filter for suppressing a leakage component of the first radio reference signal included in the second radio multiplexed signal received by the second receiver;
Included in the first radio multiplexed signal based on the first radio reference signal contained in the first radio multiplexed signal in which the leakage component of the second radio reference signal is suppressed by the first filter A first reception-side frequency converter that generates a first modulated signal by frequency down-converting the first radio modulated signal,
Included in the second radio multiplexed signal based on the second radio reference signal contained in the second radio multiplexed signal in which the leakage component of the first radio reference signal is suppressed by the second filter And a second reception-side frequency converter that generates a second modulated signal by frequency down-converting the second radio modulated signal.

  According to the microwave radio receiver of the above configuration, the first and second radio multiplexed signals composed of the first and second radio reference signals and the first and second radio modulation signals of each polarization are In the received signals received by the first and second receiving units, there are main polarization components and cross-polarization components, and four types of signals are received by the antennas of the first and second receiving units. Will be. Usually, the cross polarization component is a leakage component of the antenna and is determined by the cross polarization ratio performance of the antenna. In the case of a normal microwave band antenna, the cross polarization ratio can be ensured from 20 dB to 30 dB. That is, the cross polarization component is 20 dB to 30 dB and the power level is smaller than the main polarization ratio component. (1/100 to 1/1000 power level). However, in the first and second radio multiplexed signals, since the first and second radio reference signals are sinusoidal signals, the peak power per band is 20 dB to 30 dB larger than the modulation signal. . Accordingly, the reference signal in the cross polarization component which is the leakage component of each antenna has a large peak power per band, and the first and second radio reference signals of the respective main polarization components are first and second. The frequency conversion process of the second radio modulation signal is affected, an unnecessary wave signal is generated, the frequency is down-converted, and the modulation signal causes interference and interference. Therefore, it is included in the reference signal in each cross-polarized component that is a leakage component in the signals received by the antennas of the first and second receiving units on the receiving side, that is, the first radio multiplexed signal. By suppressing the leakage component of the second wireless reference signal with the first filter and suppressing the leakage component of the first wireless reference signal included in the second wireless multiplexed signal with the second filter, The frequency conversion process using the second radio reference signal of the leakage component by the first frequency mixer and the first radio modulation signal, while the first radio reference signal and the second radio modulation of the leak component by the second frequency mixer It is possible to reduce the generation of unnecessary waves generated in the frequency conversion process using signals. As a result, it is possible to obtain a good signal quality characteristic with few unnecessary waves and interference waves from a signal in which the original main polarization component is frequency down-converted and a modulated signal is generated and reproduced.

  In the above frequency conversion process, the frequency control and phase of the oscillator in this microwave band radio receiving apparatus are configured by down-converting the radio desired signal with the transmitted first and second radio reference signals. There is no need to strictly control noise, and the configuration of the receiving device can be easily and low-cost configured.

In the microwave band radio receiver of the present invention,
A microwave band radio receiving apparatus that receives first and second radio multiplexed signals transmitted from the transmitting side with different polarizations, respectively,
The first radio multiplexed signal is composed of a first radio modulation signal and a first radio reference signal arranged in a frequency band above the first radio modulation signal,
The second radio multiplexed signal is composed of a second radio modulation signal and a second radio reference signal arranged in a frequency band lower than the second radio modulation signal,
A first receiver for receiving the first radio multiplexed signal;
A second receiver for receiving the second radio multiplexed signal;
A first reception-side intermediate frequency conversion unit that down-converts the first radio multiplexed signal received by the first reception unit into an intermediate frequency band;
A second reception-side intermediate frequency conversion unit that down-converts the second radio multiplexed signal received by the second reception unit into an intermediate frequency band;
A third filter for suppressing an intermediate frequency leakage component of the second radio reference signal included in the first intermediate frequency multiplexed signal frequency-converted to the intermediate frequency band by the first reception-side intermediate frequency conversion unit; ,
A fourth filter for suppressing an intermediate frequency leakage component of the first radio reference signal included in the second intermediate frequency multiplexed signal frequency-converted to the intermediate frequency band by the second reception-side intermediate frequency converter; ,
The first intermediate frequency reference signal corresponding to the first wireless reference signal included in the first intermediate frequency multiplexed signal, in which the intermediate frequency leakage component of the second wireless reference signal is suppressed by the third filter. To generate a first modulated signal by frequency down-converting a first intermediate frequency modulation signal corresponding to the first radio modulation signal included in the first intermediate frequency multiplexed signal. A receiving side frequency converter,
The second intermediate frequency reference signal corresponding to the second wireless reference signal included in the second intermediate frequency multiplexed signal, in which the intermediate frequency leakage component of the first wireless reference signal is suppressed by the fourth filter. Based on the second intermediate frequency modulation signal, the second intermediate frequency modulation signal corresponding to the second radio modulation signal included in the second intermediate frequency multiplexed signal is frequency down-converted to generate a second modulation signal. And a reception-side frequency converter.

  According to the microwave band radio receiver having the above-described configuration, the first and second radio multiplexed signals received by the first and second receivers are respectively the first and second reception-side intermediate frequency conversion units. Thus, it is possible to sharpen the attenuation / suppression characteristics of the circuits of the third and fourth filters due to the low frequency by down-converting the frequency to a different intermediate frequency band by different local oscillators. Become. For this reason, it is possible to easily suppress and reduce the reference signal of the leakage component by the third filter and the fourth filter, respectively, and to obtain a good signal quality characteristic with less interference after frequency conversion. .

  The microwave band wireless transmission / reception system according to the present invention includes any one of the above microwave band wireless transmission apparatuses and the above microwave band wireless reception apparatus.

  According to the microwave band radio transmission / reception system of the above embodiment, each of the two types of modulation signals input to the microwave band radio transmission apparatus is restored and generated by the microwave band radio reception apparatus even if they are in the same frequency band. The modulated signal can realize good received signal characteristics with less interference.

  As is clear from the above, according to the microwave band radio transmission apparatus, the microwave band radio reception apparatus, and the microwave band radio transmission / reception system of the present invention, two types of modulation signals input to the microwave band radio transmission apparatus are received. Two types of high-quality modulated signal characteristics with little interference and unnecessary waves can be obtained even in the same frequency band, and a low-cost microwave radio with a simple configuration, wide bandwidth, and stable frequency A transmitter, a microwave band wireless receiver, and a microwave band wireless transmission / reception system can be realized.

  Hereinafter, a microwave band radio transmission apparatus, a microwave band radio reception apparatus, and a microwave band radio transmission / reception system of the present invention will be described in detail with reference to the illustrated embodiments. Here, the microwave band refers to a frequency band including a microwave band and a millimeter wave band.

(First embodiment)
FIG. 1 shows the configuration of a microwave band wireless transmission / reception system according to a first embodiment of the present invention. The same components as those of the conventional microwave band wireless transmission / reception system shown in FIGS. 7 and 8A and 8B are denoted by the same reference numerals. In the first embodiment, the radio frequency band is described as a millimeter wave band.

  As shown in FIG. 1, in the above microwave band wireless transmission / reception system, two types of first satellite broadcast wave (first modulated signal 5a) and second satellite broadcast wave (second modulated signal 5b) are provided. The block diagram in the case of receiving a broadcast wave simultaneously and transmitting by radio | wireless is shown. This microwave band radio transmission / reception system includes a millimeter wave band radio transmission apparatus 9-1 as an example of a microwave band radio transmission apparatus and a millimeter wave band radio reception apparatus 10-1 as an example of a microwave band radio reception apparatus. I have.

  The millimeter wave band wireless transmission device 9-1 includes a reference signal adding circuit 2a that converts the first modulated signal 5a from the first satellite broadcast antenna 1a into an intermediate frequency and applies a first reference signal, and a first reference signal adding circuit 2a. A reference signal adding circuit 2b for converting the first modulated signal 5b from the second satellite broadcast antenna 1b to an intermediate frequency to give a second reference signal, and supplying the first reference signal to the reference signal adding circuit 2a And a frequency divider 210 that divides the first reference signal from the reference signal source 2c and supplies the second reference signal to the reference signal adding circuit 2a (frequency divider in FIG. 1). ), A frequency conversion / transmission circuit 3a that frequency-converts and transmits the multiplexed signal to which the first reference signal from the reference signal addition circuit 2a is added, and a second reference from the reference signal addition circuit 2b. Frequency up-converting multiple signals with added signals And a frequency multiplier 7a for supplying a local oscillation signal to the frequency conversion / transmission circuit 3a based on the first reference signal from the reference signal source 2c (multiplier in FIG. 1) A frequency multiplier 7b (multiplier in FIG. 1) that supplies a local oscillation signal to the frequency conversion / transmission circuit 3b based on the first reference signal from the reference signal source 2c, and the frequency conversion / transmission A vertically polarized transmitting antenna 4a for transmitting a vertically polarized radio signal from the circuit 3a, and a horizontally polarized transmitting antenna 4b for transmitting a horizontally polarized radio signal from the frequency converting / transmitting circuit 3b; It has.

  The reference signal adding circuit 2a includes an amplifier 203a in which the output side of the transmission antenna 4a is connected to the input, and a frequency mixer 201a as an example of a first transmission-side intermediate frequency converter having an input connected to the output of the amplifier 203a. A filter 205a having an input connected to the output of the frequency mixer 201a, an amplifier 206a having an input connected to the output of the filter 205a, and a power combiner 202a having the output of the amplifier 206a connected to one input. The distributor 200a to which the first reference signal from the reference signal source 2c is input, the input is connected to one output of the distributor 200a, and the output is connected to the other input of the power combiner 202a. And an amplifier 207a. The power combiner 202a and the amplifier 207a constitute a first reference signal adding unit.

  The reference signal adding circuit 2b includes an amplifier 203b whose output side of the transmission antenna 4b is connected to the input, and a frequency mixer as an example of a second transmission side intermediate frequency conversion unit whose input is connected to the output of the amplifier 203b. 201b, a filter 205b whose input is connected to the output of the frequency mixer 201b, an amplifier 206b whose input is connected to the output of the filter 205b, and a power combiner whose output is connected to one of the inputs 202b, a filter 208 to which the second reference signal from the frequency divider 210 is input, an amplifier 209 whose input is connected to the output of the filter 208, and a distribution whose input is connected to the output of the amplifier 209 200b and an amplifier having an input connected to one output of the distributor 200b and an output connected to the other input of the power combiner 202b And a 07b. The power combiner 202b and the amplifier 207b constitute a second reference signal adding unit.

  The frequency conversion / transmission circuit 3a includes a frequency mixer 301a as an example of a first transmission-side microwave frequency conversion unit whose input is connected to the output of the power combiner 202a of the reference signal addition circuit 2a; The filter 302a has an input connected to the output of the mixer 301a, and a transmission amplifier 303a to which the output of the filter 302a is connected. The frequency mixer 301a performs frequency up-conversion based on the local oscillation signal from the frequency multiplier 7a. The transmission amplifier 303a and the transmission antenna 4a constitute a first transmission unit.

  On the other hand, the frequency conversion / transmission circuit 3b includes a frequency mixer 301b whose input is connected to the output of the power combiner 202b of the reference signal addition circuit 2b, and a filter 302b whose input is connected to the output of the frequency mixer 301b, A transmission amplifier 303b to which the output of the filter 302b is connected. The frequency mixer 301b performs frequency up-conversion based on the local oscillation signal from the frequency multiplier 7b. The transmission amplifier 303b and the transmission antenna 4b constitute a second transmission unit.

  A frequency mixer 201a as an example of the first transmission-side intermediate frequency conversion unit of the reference signal addition circuit 2a and a frequency mixer 301a as an example of the first transmission-side microwave frequency conversion unit of the frequency conversion / transmission circuit 3a. A first transmission-side frequency conversion unit is configured. The frequency mixer 201b as an example of the second transmission-side intermediate frequency conversion unit of the reference signal addition circuit 2b and the frequency mixer as an example of the second transmission-side microwave frequency conversion unit of the frequency conversion / transmission circuit 3b. 301b constitutes a second transmission side frequency converter.

  The millimeter-wave band radio receiving apparatus 10-1 receives a vertically polarized radio receiving antenna 14a for receiving a vertically polarized radio signal from the transmitting side and a horizontally polarized radio signal from the transmitting side. A horizontally polarized wave receiving antenna 14b, a microwave receiving circuit unit 12c that receives the vertically polarized first radio multiplexed signal 72a from the receiving antenna 14a and down-converts the frequency, and a horizontal wave from the receiving antenna 14b. A microwave receiving circuit unit 12d that receives the polarized second radio multiplexed signal 72b and down-converts the frequency, a filter 77a that removes unnecessary waves from the microwave receiving circuit unit 12c, and the microwave receiving unit. A filter 77b for removing unnecessary waves from the signal from the circuit unit 12d, an amplifier 76a for amplifying the first modulated signal from the filter 77a, and a first filter from the filter 77b. And a amplifier 76b for amplifying the modulated signal.

  The microwave receiving circuit unit 12c has a low noise amplifier 110a whose input is connected to the output of the receiving antenna 14a, a filter 111a whose input is connected to the output of the low noise amplifier 110a, and an input to the output of the filter 111a. Is connected to the first frequency mixer 122a as an example of the first receiving side frequency converter. The reception antenna 14a and the low noise amplifier 110a constitute a first reception unit.

  The microwave receiving circuit unit 12d has a low noise amplifier 110b whose input is connected to the output of the receiving antenna 14b, a filter 111b whose input is connected to the output of the low noise amplifier 110b, and an input to the output of the filter 111b. Is connected to the second frequency mixer 122b as an example of the second receiving side frequency converter. The reception antenna 14b and the low noise amplifier 110b constitute a second reception unit.

  Next, the operations of the microwave band wireless transmission device 9-1 and the microwave band wireless reception device 10-1 will be described with reference to FIG.

  First, in the microwave radio transmission apparatus 9-1, the first modulated signal 5a (fIF1a) from the first satellite broadcast antenna 1a and the second modulated signal 5b received from the second satellite broadcast antenna 1b. (fIF1b) is input to the reference signal addition circuits 2a and 2b.

  Here, the first modulated signal 5a is amplified by the amplifier 203a and level-adjusted, and then input to the frequency mixer 201a. The second modulated signal 5b is amplified and amplified by the amplifier 203b, and then input to the frequency mixer 201b. In the reference signal addition circuit 2a, the frequency is up-converted by the first reference signal (fLO1) of the sine wave distributed from the reference signal source 2c by the distributor 200a, and the lower sideband signal (LSB) is selected by the filter 205a. After that, the level is amplified by the amplifier 206a. Further, the level of the first reference signal (fLO1) of the sine wave distributed from the reference signal source 2c by the distributor 200a is adjusted by the amplifier 207a, and the first reference signal (fLO1) is added by the power combiner 202a. Thus, an intermediate frequency multiplexed signal 71a composed of the first reference signal (fLO1) and the first modulated signal (fLO1-fIF1a) is generated. In the following description, the state of the frequency as the reference signal and the modulation signal is shown using the expression format “(reference signal, modulation signal) = (,)”.

(1) Operation of reference signal adding circuit 2a: generation of intermediate frequency multiplexed signal 71a
(First reference signal, first modulation signal) = (fLO1, fLO1-fIF1a)
In the first embodiment, fLO1 = 5.62 GHz, and the frequency of the first modulation signal 5a is
fIF1a = 1.0 to 2.1 GHz
Then,
fLO1-fIF1a = 4.62 GHz to 3.52 GHz
It becomes.

  On the other hand, in the reference signal adding circuit 2b, a signal obtained by frequency-dividing the second reference signal (fLO1) of the sine wave from the reference signal source signal 2c (in the case of the first embodiment, a signal divided by 1/2) Is used to up-convert the frequency. In the up-conversion, the signal divided by ½ obtains only a fundamental wave signal divided by ½ by the filter 208 ((½) · fLO1 component). Thereafter, the fundamental wave signal from the filter 208 is level-adjusted by the amplifier 209 and divided into two by the distributor 200b, one of which is used as a local oscillation signal of the frequency converter 201b, and the other is the second reference signal. Is added by the power combiner 202 as a ½ frequency reference signal ((½) · fLO1). Here, the signal whose frequency is up-converted by the local oscillation signal is selected by the filter 205b as the upper sideband signal (USB), amplified by the amplifier 206b, and level-adjusted. As a result, an intermediate frequency multiplexed signal 71b composed of the second reference signal ((1/2) · fLO1) and the second modulated signal ((1/2) · fLO1 + fIF1b) is generated. The frequency relationship is as follows.

(2) Operation of reference signal adding circuit 2b: generation of intermediate frequency multiplexed signal 71b
(Second reference signal, second modulation signal) = ((1/2) · fLO1, (1/2) · fLO1 + fIF1b)
= (FLO1B, fLO1B + fIF1b)
Here, fLO1B = (1/2) · fLO1.
In the first embodiment, fLO1B = 2.81 GHz, and the second modulation signal frequency is
fIF1b = 1.0 GHz to 2.1 GHz
Then,
fLO1B + fIF1b = 3.81 GHz to 4.91 GHz
It becomes.

  Next, the intermediate frequency multiplexed signal 71a is input to the frequency converting / transmitting circuit 3a, and the intermediate frequency multiplexed signal 71b is input to the frequency converting / transmitting circuit 3b.

  Frequency conversion to a radio frequency is frequency up-converted by frequency mixers 301a and 301b. In the first embodiment, the frequency mixers 301a and 301b are even harmonic mixers with anti-parallel diode pairs that are ½ harmonic mixers, so the frequency (fLO2 ′) input to the local oscillator is The frequency is approximately half of the radio frequency to be up-converted. For example, when the radio frequency is 60 GHz, the local oscillation frequency is 27 GHz to 30 GHz (28.1 GHz in the first embodiment), and furthermore, a frequency multiplier of 5 times type is used for the frequency multipliers 7a and 7b. The frequency input to the frequency multipliers 7a and 7b is a 5.62 GHz signal. This is the first reference signal from the reference signal source 2c, and can directly excite the frequency multipliers 7a and 7b.

In other words, if the local oscillation frequency necessary for up-conversion to the radio frequency band by the fundamental frequency converter is fLO2, the local oscillation frequency fLO2 and the local harmonic input to the even harmonic mixer used in the frequency mixers 301a and 301b It has the following relationship with the oscillation frequency fLO2 ′.
fLO2 = 2 ・ fLO2 '
Further, since the frequency input by the 5 × frequency multiplier is the frequency fLO1 of the first reference signal, the following relationship is established.
fLO2 '= 5 ・ fLO1
Therefore,
fLO2 = 10 ・ fLO1
In this first embodiment,
fLO2 = 10 × 5.62 GHz = 56.2 GHz
It becomes.

The signal up-converted to the radio frequency by the frequency mixer 301b selectively passes the upper-band (USB) signal by the filter 302a, is amplified to an appropriate level by the transmission amplifier 303a, and is transmitted to the vertical polarization transmission antenna 4a. Is output from. The signal up-converted to the radio frequency by the frequency mixer 301b is selectively passed through the upper sideband (USB) signal by the filter 302b, amplified to an appropriate level by the transmission amplifier 303b, and transmitted for horizontal polarization. Output from the antenna 4b.
Here, the vertically polarized wave transmitting antenna 4a and the horizontally polarized wave transmitting antenna 4b are emitted into the space as vertically polarized wave and horizontally polarized wave signals, respectively.

  Specifically, the first radio multiplexed signal 72a is emitted into the space as vertical polarization composed of the first radio reference signal 771a and the first radio modulation signal 772a from the transmission antenna 4a for vertical polarization. The The frequency relationship at this time is as follows (shown in FIG. 2A (a)).

(3) Emission of the first radio multiplexed signal 72a from the transmitting antenna 4a as vertical polarization:
(First radio reference signal, first radio modulation signal) = (fLO1 + fLO2, fLO1−fIF1a + fLO2)
In the first embodiment, the frequency of the first radio reference signal is
fLO1 + fLO2 = 61.82GHz
And the frequency of the first radio modulated signal is
fLO1-fIF1a + fLO2 = 60.82 GHz to 59.72 GHz
It is.

  On the other hand, from the transmission antenna 4b for horizontal polarization, the second radio multiplexed signal 72b is emitted into the space as horizontal polarization composed of the second radio reference signal 771b and the second radio modulation signal 772b. The frequency relationship is as follows (shown in FIG. 2A (b)).

(4) Release of second radio multiplexed signal 72b from transmitting antenna 4b as horizontal polarization:
(Second radio reference signal, second radio modulation signal) = (fLO1B + fLO2, fLO1B + fIF1b + fLO2)
In the first embodiment, the frequency of the second radio reference signal is
fLO1B + fLO2 = 59.01GHz
And the frequency of the second radio modulated signal is
fLO1B + fIF1b + fLO2 = 60.01 GHz to 61.11 GHz
It is.

  The signal as described above is emitted from the microwave radio transmitting apparatus 9-1 into space.

  Next, in the microwave radio receiver 10-1 on the receiving side, the first and second radio multiplexed signals 72a and 72b are received by the receiving antennas 14a and 14b having the same polarization as the transmitting side, respectively. After receiving by the receiving antennas 14a and 14b, the first and second radio multiplexed signals 72a and 72b are once amplified by the low noise amplifiers 110a and 110b. Thereafter, the desired wave is passed through the filters 111a and 111b, but the two filter characteristics are different.

  The filter characteristics of the filters 111a and 111b will be described with reference to FIGS. 3 (a) and 3 (b).

  In the first radio multiplexed signal 72a received by the receiving antenna 14a, the original vertical polarization (main polarization) component (first radio reference signal 771a, first radio modulation signal 772a) and the antenna cross polarization Due to the imperfection of the wave, a slight leakage component 72b (second radio reference signal 771b, second radio modulation signal 772b) of the horizontal polarization component is included. On the frequency axis, the second radio reference signal 771b which is the second reference signal of the leakage component and the first radio reference signal 771a of the original main polarization component have a frequency of (1/2) · Since fLO1 (2.81 GHz in this first embodiment) is separated, the first wireless reference signal 771b, which is the second reference signal of the leakage component, can be suppressed by the first filter 111a.

  For example, a distributed constant filter integrally formed with an active element on an MMIC chip can suppress 6 dB or more. By suppressing the reference signal 771b of this leakage component, there is no other sine wave signal (the level is sufficiently small) except for the first wireless reference signal 771a (sine wave). In the frequency mixer 122a, the first radio modulation signal 772a can be frequency down-converted (multiplied) using the first radio reference signal 771a of the original main polarization component. As a result, a first modulated signal 5a (fIF1a) that is an input signal on the transmission side can be obtained (in the case of the first embodiment, the first modulated signal is a signal of the first satellite broadcast). Here, the second radio multiplexed signal (radio reference signal 771b, radio modulation signal 772b) of the leakage component is suppressed by 20 dB to 30 dB due to the cross polarization ratio characteristic of the antenna, and the first filter 111a. As a result, the wireless reference signal 771b is further suppressed, so that the second wireless reference signal 772b, which is the second reference signal of the leakage component, is frequency-converted (multiplied) by the second wireless modulation signal 772b of the leakage component. However, only a very small signal is generated, and interference / interference with the original signal hardly occurs by the frequency down-conversion by the first frequency mixer 122a. In addition, there is a possibility that the second radio modulation signal 772b of the leak component is frequency down-converted by the first radio reference signal 771a that is the original first reference signal, but the second modulation that is the leak component is generated. Since the signal component is a signal that is 20 dB to 30 dB lower than the cross polarization ratio of the antenna as compared with the first modulated signal component that is the main polarization component, the frequency down-converted output is extremely small. The influence of interference and interference is small. Even if the second radio modulated signal 772b of this leakage component is frequency down-converted by the first radio reference signal 771a which is the original first reference signal, Is down-converted to a different frequency band, so there is little influence of direct / interference interference in the entire band of the received output.

  If the first frequency mixer 122a is a two-terminal mixer using a microwave transistor (a mixer having a local oscillation port and an RF port in common), the frequency can be efficiently down-converted by the gain of the transistor.

  The frequency relationship of this frequency down-conversion is as follows. An example of spectrum arrangement after down-conversion is shown in FIGS. 2B (a) and 2 (b).

(5) Frequency down-conversion on the receiving antenna 14a side:
Frequency of first radio reference signal-frequency of first radio modulation signal
= (FLO1 + fLO2)-(fLO1-fIF1a + fLO2)
= FIF1a
In the first embodiment, the first modulation signal 5a (fIFa = 1.0 GHz to 2.1 GHz) input to the microwave radio transmission apparatus 9-1 can be generated (reproduced).

  On the other hand, in the second radio multiplexed signal 72b received by the reception antenna 14b, the horizontal polarization component (second radio reference signal 771b and second radio modulation signal 772b) which is the original main polarization, and the antenna Due to the imperfection of the cross polarization, a slight leakage component 72a (first radio reference signal 771a, first radio modulation signal 772a) of the vertical polarization component is included. On the frequency axis, the first radio reference signal 771a which is the first reference signal of the leakage component and the second radio reference signal 771b of the original main polarization component have a frequency of (½) · Since it is separated by fLO1 (2.81 GHz in this first embodiment), the second filter 111b can suppress the first wireless reference signal 771a that is the first reference signal that is a leakage component. . For example, a distributed constant filter integrally formed with an active element on an MMIC chip can suppress 6 dB or more. By suppressing the first wireless reference signal 771a that is the first reference signal of the leakage component, the second frequency mixer 122b in the next stage uses the second sine wave that is the original main polarization component. Using the wireless reference signal 771b, the second wireless modulation signal 772b can be frequency down-converted (multiplied). As a result, a second modulated signal (fIF1b) that is an input signal on the transmission side can be obtained. In the case of the first embodiment, the second modulated signal is a second satellite broadcast signal.

  Here, the first radio multiplexed signal (radio reference signal 771a, radio modulation signal 772a) of the leakage component is suppressed by 20 dB to 30 dB due to the cross polarization ratio characteristic of the antenna, and further, the radio reference is performed by the second filter 111b. The signal 771a is suppressed. For this reason, even if the first wireless reference signal 772a which is the first reference signal of the leakage component is frequency-converted (multiplied) by the first wireless modulation signal 772a of the leakage component, only a very small signal is generated. In the frequency down-conversion by the second frequency mixer 122b, interference and interference with the original signal hardly occur.

  In addition, there is a possibility that the first radio modulation signal 772a of the leakage component is frequency down-converted by the second radio reference signal 771b that is the original second reference signal, but the first radio signal that is the leakage component. Since the modulation signal component is a signal that is 20 to 30 dB lower than the cross polarization ratio of the antenna compared to the second radio modulation signal component that is the main polarization component, the output that is frequency down-converted is Extremely small and less affected by interference and interference. Even if the first radio modulated signal 772a of the leakage component is frequency down-converted by the second radio reference signal 771b which is the original second reference signal, the second radio modulated signal of the main polarization Therefore, it is less likely to be affected by direct / interference interference in the entire band of the received output.

  If the second frequency mixer 122b is a two-terminal mixer using a microwave transistor (a mixer having a local oscillation port and an RF port in common), the frequency can be efficiently down-converted by the gain of the transistor. The frequency relationship of this down conversion is as follows.

(6) Frequency down-conversion on the receiving antenna 14b side:
Second radio modulation signal frequency-second radio reference signal frequency
= (1/2) · fLO1 + fIF1b + fLO2)-(1/2) · fLO1 + fLO2
= FIF1b
In the first embodiment, the second modulated signal (fIFb = 1.0 GHz to 2.1 GHz) input to the microwave radio transmitting apparatus 9-1 can be generated (reproduced).

  As described above, signals obtained by down-conversion of the first and second frequency mixers 122a and 122b and unnecessary wave removal by the filters 77a and 77b are appropriately amplified by the amplifiers 76a and 76b and output from the output terminals 15a and 15b. It is connected to the satellite broadcast tuner 30 via the switch 31. A signal from the satellite broadcast tuner 30 is input to the TV receiver 31.

  With the configuration as described above, even if the frequency bands of the two types of first and second modulation signals input are the same in the microwave radio transmitting apparatus 9-1, the first peak power level is large. By reversing the frequency arrangement of the radio reference signal and the second radio reference signal with respect to the first and second radio modulation signals, the frequency down-conversion is performed by the microwave radio receiver 10-1, and then due to the leakage component The signal can be brought to a frequency different from the frequency band so that the signal is originally restored (demodulated), not affected by the entire demodulation frequency band, and the influence of the leakage components of each other. Since the reference signal component having a large peak power per band, particularly on the leakage component side, can be suppressed at the reception-side radio frequency (in this first embodiment, millimeter wave frequency) stage, the second and first leakage components are suppressed. Wireless reference signal Can prevent the first and second radio modulated signals from being frequency down-converted, and the demodulated first and second modulated signals can realize good reception characteristics with less interference. it can.

  As described above, in this configuration, the microwave band wireless transmission device 9-1 is a single reference signal source having a low frequency, and all frequency relationships are uniquely determined. 1 is remarkably easy to control, and since there is only one oscillation source, a simple and stable microwave band wireless transmission device 9-1 can be configured without the influence of interference between the oscillation sources. Further, on the receiving side, since the microwave receiving circuit units 12c and 12d do not require an oscillation source such as a local oscillator, a circuit configuration with a low current consumption and a simple one-chip IC can be achieved.

  With the configuration described above, even if the two types of input signals are in the same frequency band, the broadcast wave signal demodulated (reproduced) on the receiving side can achieve good reception characteristics with less interference.

  As shown in FIG. 4, the first modulated signal 5a is a satellite broadcast signal (1000 MHz to 2100 MHz) and the second modulated signal 5b is a different frequency band such as a terrestrial broadcast signal (470 MHz to 770 MHz). Therefore, it is possible to reproduce (demodulate) a high-quality modulated signal with few unnecessary waves such as interference and interference waves, and to obtain good reception characteristics.

  According to the microwave band wireless transmission / reception system of the first embodiment, it is possible to easily realize good transmission characteristics with less interference even when two modulated signals wirelessly transmitted in the microwave band are in the same frequency band. it can.

  Further, by generating a second reference signal by frequency-dividing the first reference signal by the frequency divider 210, only one reference signal source is required, and frequency control is remarkably facilitated and oscillation is performed. There is no interference or interference caused by multiple sources. Furthermore, the microwave band wireless transmission device can be further simplified and the cost can be reduced.

  Further, even if two input first and second modulation signals 5a and 5b are in the same frequency band, the first modulation signal 5a is frequency up-converted to a microwave band as a lower side band modulation signal. Then, the second modulation signal 5b is frequency up-converted to the microwave band as the modulation signal of the upper side band, so that the first radio reference signal 771a is added to the first radio modulation signal 772a of the lower side band. The first radio multiplexed signal 72a is configured, and the second radio multiplexed signal 72b in which the second radio reference signal 771b is added to the first radio modulated signal 772b in the upper sideband is configured. As a result, the leakage wave component when the frequency is converted on the receiving side is greatly different from the frequency bands of the demodulated first and second modulated signals, so that the interference / interference characteristics can be further improved. Therefore, the independence between the second modulated signals can be further increased.

  Further, according to the millimeter wave band wireless transmission device 9-1, the frequency is converted to the first reference signal by the first transmission intermediate frequency conversion unit (201a) and the first reference signal addition unit (202a). Generated by the first intermediate frequency multiplexed signal 71a comprising the first modulated signal, and the second transmission side intermediate frequency conversion unit (201b) and the second reference signal addition unit (202b) The first intermediate frequency multiplexed signal 71a is generated as a second intermediate frequency multiplexed signal 71b composed of the reference signal and the second modulated signal frequency-converted, and the first transmission-side microwave frequency converter (301a) is generated. Thus, the second intermediate frequency multiplexed signal 71b is frequency up-converted to the millimeter wave band by the second transmission side microwave frequency converter (301b). Accordingly, a harmonic mixer such as an even harmonic mixer can be used for frequency conversion to a radio frequency, and the configuration of the local oscillator is facilitated. Further, since the power ratio between the modulation signal and the reference signal in the first and second intermediate frequency multiplexed signals 71a and 71b can be controlled by the intermediate frequency stage having a low frequency, the modulation signal and the reference in the radio frequency band can be controlled. The signal power ratio can be easily controlled to be constant.

  Further, by providing the frequency multipliers 7a and 7b that generate the local oscillation signal by multiplying the frequency of the first reference signal, the local oscillation frequency can be easily configured and the frequency control can be performed in a low frequency band. Since it can be controlled by the reference signal, stable wireless transmission can be performed.

  According to the millimeter-wave band radio receiving apparatus 10-1, the second radio wave signal included in the first radio multiplexed signal among the respective cross-polarized wave components which are leakage components in the signals received by the receiving antennas 14a and 14b. In the frequency conversion process, the leakage component of the wireless reference signal is suppressed by the first filter 111a, and the leakage component of the first wireless reference signal included in the second wireless multiplexed signal is suppressed by the second filter 111b. Reduces the generation of unwanted waves, and the original main polarization component is frequency down-converted, and the modulated signal is generated / reproduced to obtain good signal quality characteristics with less unwanted waves and interference waves. it can.

(Second embodiment)
FIG. 5 shows the configuration of a microwave band wireless transmission / reception system according to the second embodiment of the present invention. The same components as those in the microwave band wireless transmission / reception system of the first embodiment are denoted by the same reference numerals. In the twelfth embodiment, the radio frequency band is described as a millimeter wave band.

  As shown in FIG. 5, in the above microwave band wireless transmission / reception system, two types of first satellite broadcast wave (first modulated signal 5a) and second satellite broadcast wave (second modulated signal 5b) are provided. The block diagram in the case of receiving a broadcast wave simultaneously and transmitting by radio | wireless is shown. This microwave band radio transmission / reception system includes a millimeter wave band radio transmission apparatus 9-2 as an example of a microwave band radio transmission apparatus and a millimeter wave band radio reception apparatus 10-2 as an example of a microwave band radio reception apparatus. I have. The millimeter wave band wireless transmission device 9-2 has the same configuration as the millimeter wave band wireless transmission device 9-1 of the first embodiment.

  The millimeter-wave band radio receiving apparatus 10-2 includes a frequency conversion unit 112a, a reference signal reproduction / frequency conversion circuit 12Ua as an example of a first reception side frequency conversion unit, and a second reception side intermediate frequency. A frequency conversion unit 112b as an example of a conversion unit and a reference signal reproduction / frequency conversion circuit 12Ub as an example of a second reception-side frequency conversion unit are provided.

  The frequency converter 112a includes a low noise amplifier 110a whose input is connected to the output of the receiving antenna 14a, a filter 111a whose input is connected to the output of the low noise amplifier 110a, and an input connected to the output of the filter 111a. The frequency mixer 119a as an example of the first reception-side intermediate frequency conversion unit and a local oscillator 8a that outputs a local oscillation signal to the frequency mixer 119a are provided. The reception antenna 14a and the low noise amplifier 110a constitute a first reception unit.

  On the other hand, the frequency converter 112b has a low noise amplifier 110b whose input is connected to the output of the receiving antenna 14b, a filter 111b whose input is connected to the output of the low noise amplifier 110b, and an input to the output of the filter 111b. Are connected to each other, a frequency mixer 119b as an example of a second reception-side intermediate frequency converter, and a local oscillator 8b that outputs a local oscillation signal to the frequency mixer 119b. The reception antenna 14b and the low noise amplifier 110b constitute a second reception unit.

The reference signal reproduction / frequency conversion circuit 12Ua has a third filter 172a to which the signal from the frequency mixer 119a of the frequency conversion unit 112a is input, and a signal whose input is connected to the output of the third filter 172a. A distribution circuit 161a; an intermediate frequency amplifier 159a whose input is connected to one output of the signal distribution circuit 161a; a transmission line 162a whose one end is connected to the output of the intermediate frequency amplifier 159a; A frequency mixer 12a as an example of a first reception-side frequency conversion unit whose end is connected to one input, a bandpass filter 171a whose input is connected to the other output of the signal distribution circuit 161a, and the bandpass filter An amplifier 180a whose input is connected to the output of 171a, and a bandpass filter whose input is connected to the output of the amplifier 180a. 171a, an amplifier 180a having an input connected to the output of the bandpass filter 171a, a transmission line 163a having one end connected to the output of the amplifier 180a and the other input connected to the other input of the frequency mixer 12a, And a filter 175a whose input is connected to the output of the frequency mixer 12a, and an amplifier 195a whose input is connected to the output of the filter 175a and whose output is connected to the output terminal 15a.

On the other hand, the reference signal reproduction / frequency conversion circuit 12Ub has a fourth filter 172b to which the signal from the frequency mixer 119b of the frequency converter 112b is input, and a signal whose input is connected to the output of the fourth filter 172b. A distribution circuit 161b, an intermediate frequency amplifier 159b whose input is connected to one output of the signal distribution circuit 161b, a transmission line 162b whose one end is connected to the output of the intermediate frequency amplifier 159b, and the other of the transmission line 162b. A frequency mixer 12b as an example of a second reception-side frequency conversion unit whose end is connected to one input, a bandpass filter 171b whose input is connected to the other output of the signal distribution circuit 161b, and the bandpass filter An amplifier 180b whose input is connected to the output of 171b, and a bandpass filter whose input is connected to the output of the amplifier 180b 171b, an amplifier 180b whose input is connected to the output of the bandpass filter 171b, a transmission line 163b whose one end is connected to the output of the amplifier 180b and the other end is connected to the other input of the frequency mixer 12b, It has a filter 175b whose input is connected to the output of the frequency mixer 12b, and an amplifier 195b whose input is connected to the output of the filter 175b and whose output is connected to the output terminal 15b.

  Since amplifiers 159a and 159b are included in the first path (transmission line 162a and 162b side) to the frequency mixers 12a and 12b, the first path and the second path (transmission line 163a and 163b side). The loop L1 (169a, 169b) constituted by and becomes a negative feedback loop by the isolation action of the amplifiers 159a, 159b, and a stable loop can be obtained. Further, the power balance between the first modulated signal and the first reference signal and the first reference signal are determined by the amplification factors of the amplifiers 159a and 159b and the amplification factors of the transmission lines 162a and 162b and the amplifiers 180a and 180b which are variable attenuators. The power balance between the second modulation signal and the second reference signal can be adjusted.

  FIGS. 6A (a) and 6 (b) show the frequency arrangement in the radio frequency band in the microwave radio transmission / reception system, and FIGS. 6B (a) and 6 (b) show the intermediate frequencies on the receiving side. The frequency arrangement in the band is shown.

  The microwave band wireless transmission device 9-2 of the second embodiment is exactly the same as that of the first embodiment, and signals as shown in (7) and (8) are radiated into the space.

(7) Emission of the first radio multiplexed signal 72a from the transmitting antenna 4a as vertical polarization:
(First radio reference signal, first radio modulation signal) = (fLO1 + fLO2, fLO1−fIF1a + fLO2)
In the second embodiment, the first radio reference signal is
fLO1 + fLO2 = 61.82GHz
And the first radio modulated signal is
fLO1-fIF1a + fLO2 = 60.82 GHz to 59.72 GHz
It is.

(8) Release of the second radio multiplexed signal 72b from the transmitting antenna 4b as horizontal polarization:
(Second radio reference signal, second radio modulation signal) = (fLO1B + fLO2, fLO1B + fIF1b + fLO2)
In the second embodiment, the second radio reference signal is
fLO1B + fLO2 = 59.01GHz
And the second radio modulated signal is
fLO1B + fIF1b + fLO2 = 60.01 GHz to 61.11 GHz
It is.

  In the microwave radio receiver 10-2, the first and second radio multiplexed signals 72a and 72b are received by the receiving antennas 14a and 14b having the same polarization as the transmitting side, respectively. The first and second radio multiplexed signals 72a and 72b received by the receiving antennas 14a and 14b are once amplified by the low noise amplifiers 110a and 110b, and the image signals of the radio multiplexed signals are removed by the filters 111a and 111b. The frequency mixers 119a and 119b down-convert the frequency to an intermediate frequency band (IF band).

  In the second embodiment, fLO3 = 53.2 GHz and fLO4 = 55.6 GHz are used as an example. On the receiving side, if a second harmonic even harmonic mixer using an antiparallel diode pair, which is a harmonic mixer, is used as the frequency mixer 119a, 119b, the frequency input to the local oscillator is 26. 6 GHz, and 27.8 GHz for fLO4.

  Here, on the receiving antenna 14a side, the frequency is converted into the following IF band by the local oscillator fLO3. The main polarization component is frequency down-converted to the frequency band shown in (9), and the cross polarization component, which is a leakage component, is frequency down-converted to the frequency band shown in (10).

(9) First frequency down-conversion of the main polarization signal received from the receiving antenna 14a
(First IF reference signal, first IF modulation signal)
= (FLO1 + (fLO2-fLO3), fLO1-fIF1a + (fLO2-fLO3))
In this second embodiment,
(fLO1 + (fLO2-fLO3)) = 8.62 GHz
fLO1-fIF1a + (fLO2-fLO3) = 7.62 GHz to 6.52 GHz
It becomes.

(10) First frequency down-conversion of cross-polarized signal received from receiving antenna 14a
(Second leaky IF reference signal, second leaky IF modulated signal)
= (FLO1B + (fLO2-fLO3), fLO1B + fIF1b + (fLO3-fLO3))
In this second embodiment,
fLO1B + (fLO2-fLO3) = 5.81 GHz
fLO1B + fIF1b + (fLO3-fLO3)) = 6.81 GHz to 7.91 GHz
It becomes.

  On the other hand, on the receiving antenna 14b side, the frequency is down-converted to the following IF band by the local oscillator fLO4.

(11) First frequency down-conversion of the main polarization signal received from the receiving antenna 14b
(Second IF reference signal, second IF modulation signal)
= (FLO1B + (fLO2-fLO4), fLO1B + fIF1b + (fLO2-fLO4))
In this second embodiment,
(fLO1B + (fLO2-fLO4)) = 3.41 GHz
fLO1B + fIF1b + (fLO2-fLO4) = 4.41 GHz to 5.51 GHz
It becomes.

(12) First frequency down-conversion of the cross-polarized signal received from the receiving antenna 14b
(First leakage IF reference signal, first leakage IF modulation signal)
= (FLO1 + (fLO2-fLO4), fLO1-fIF1a + (fLO2-fLO4))
In this second embodiment,
fLO1 + (fLO2−fLO4) = 6.22 GHz
fLO1-fIF1a + (fLO2-fLO4) = 5.22 GHz to 4.12 GHz
It becomes.

  FIG. 6B shows an example of a frequency arrangement relationship in the intermediate frequency band after frequency conversion of the signals from the respective receiving antennas 14a and 14b.

  On the receiving antenna 14a side, the first IF reference signal 741a of the main polarization signal and the second IF reference signal 741b which is a leakage component are separated by 1/2 fLO1 = fLO1B. In the second embodiment, the distance is about 2.81 GHz. Therefore, the second IF reference signal 741b that is a leakage component (fLO1B + (fLO2-fLO3)) is 5.81 GHz in this second embodiment, and can be suppressed by the third filter 172a.

  Here, unlike the first embodiment, since the third filter 172a suppresses the frequency in the intermediate frequency band having a low frequency as shown in FIG. 5, the steepness is reduced from the high frequency characteristics of the material characteristics at lower frequencies. It is possible to realize a filter having a high and excellent suppression characteristic. For this reason, the IF reference signal B component of the unnecessary wave can be largely suppressed / removed. As a result, the second IF reference signal is removed by the third filter (for example, a high-pass filter) 172a, and the first IF reference signal and the first IF modulated signal that are the main polarization components are selected and passed. Here, the second IF modulation signal 742b, which is a signal leakage component, is 20 dB to 30 dB smaller than the first IF modulation signal 742a of the main signal, and therefore the output frequency down-converted in the next stage is Extremely small and less affected by interference and interference. Even if the second IF modulated signal 742b of the leakage component is frequency down-converted by the first IF reference signal 741a which is the original first reference signal, the first modulated signal 5a of the main polarization Therefore, it is less likely to be affected by direct / interference interference in the entire band of the received output.

  On the other hand, on the receiving antenna 14b side, after down-converting once with the local oscillation signal (fLO4), the second IF reference signal 741b of the main polarization signal and the first IF reference signal which is a leakage component 741a is 1/2 fLO1 = fLO1B, which is about 2.81 GHz in this second embodiment. Therefore, the first IF reference signal 741a which is a leakage component (fLO1 + (fLO2-fLO4)) becomes 6.22 GHz in the second embodiment, and can be suppressed by the fourth filter 172b.

  Also here, unlike the first embodiment, as shown in FIG. 5, the configuration is such that the fourth filter 172b suppresses the frequency in the intermediate frequency band having a low frequency. A filter having a high and good suppression characteristic can be realized. Therefore, the IF reference signal A component of unnecessary waves can be largely suppressed / removed. As a result, the fourth IF (low pass filter as an example) 172b removes the first IF reference signal 741a and selects the second IF reference signal 741b and the second IF modulation signal 742b, which are the main polarization components.・ Pass through. Here, since the first IF modulated signal 742a which is a signal leakage component is 20 dB to 30 dB smaller than the main signal (second IF modulated signal 742b), the frequency down-converted output is extremely small, and interference occurs. The influence of interference is small, and even if the first IF modulated signal 742a of this leakage component is frequency down-converted by the second IF reference signal 741b which is the original second reference signal, the main polarization Since the second modulation signal is down-converted to a frequency band different from that of the second modulation signal, there is little influence of direct / interference interference in the entire band of the reception output.

  As described above, in the subsequent stage of the third and fourth filters 172a and 172b, the first reference signal and the second reference having a large power level among the cross-polarized components that become leakage components of the respective receiving antennas 14a and 14b. The signal can be almost completely removed. Therefore, satisfactory frequency conversion can be performed by the frequency conversion circuits 12c and 12d. The frequency conversion process will be briefly described below.

  On the receiving antenna 14a side, the first IF reference signal and the first IF modulated signal that have passed through the third filter 172a are divided into two by the power distributor 161a, and the first reference signal is distributed by the bandpass filter 171a. The signal fLO1 + (fLO2-fLO3) that is extracted and amplified to an appropriate level by the amplifier 180a becomes the local oscillation signal of the frequency mixer 12a. The other intermediate frequency signal (the first reference signal and the first modulation signal) divided into two by the power distributor 161a is adjusted to an appropriate level by the amplifier 159a and the attenuator 162a, and input to the frequency mixer 12a. Signal. In the frequency mixer 12a, the input signal is frequency down-converted using the extracted local oscillation signal fLO1 + (fLO2-fLO3).

  The frequency conversion process in the IF band on the receiving antenna 14a side is as follows.

(13) Frequency conversion process of first IF modulation signal (receiving antenna 14a side)
First IF reference signal-first IF modulated signal
= FLO1 + (fLO2-fLO3)-(fLO1-fIF1a + (fLO2-fLO3))
= FIF1a
On the other hand, similarly, on the receiving antenna 14b side, the frequency is down-converted by the second reference signal extraction process (the operation is the same, and the detailed description is omitted). The frequency conversion process in the IF band on the receiving antenna 14b side is as follows.

(14) Frequency conversion process of second IF modulated signal (receiving antenna 14b side)
Second IF modulation signal-second IF reference signal
= FLO1B + fIF1b + (fLO2-fLO4))-(fLO1B + (fLO2-fLO4)
= FIF1b
As an example, a signal as shown in FIG. 2B can be demodulated (reproduced).

  In the second embodiment, two types of signals of 1.0 GHz to 2.1 GHz can be demodulated (reproduced), and good reception characteristics can be obtained.

  In the above process, the two modulated signals input to the original microwave radio transmitter 9-2 are demodulated and reproduced on the receiving side, and unnecessary waves are removed by the filters 175a and 175b. After being appropriately amplified by the amplifiers 195a and 195b, the signals are output from the output terminals 15a and 15b and input to the satellite broadcast tuner 30 via the signal switch 31.

  The millimeter wave band wireless transmission / reception system of the second embodiment has the same effect as the millimeter wave band wireless transmission / reception system of the first embodiment, and according to the millimeter wave band wireless reception apparatus 10-2, the first and first The frequency band characteristics of the output signals are improved by the first and second IF modulation signal frequency down-conversion processes by the two reference signal extraction processes, and the wideband signal can be down-converted. Therefore, even if the two modulated signals input are wideband signals of 200 MHz to 2.100 MHz and the same frequency band, the reference of leakage components from the respective receiving antennas 14a and 14b at the intermediate frequency stage on the receiving side. Since the signal is suppressed / removed, the modulated signal to be restored and reproduced can realize good received signal characteristics with less interference.

  Further, according to the millimeter wave band radio receiving apparatus 10-2, the first and second radio multiplexed signals 72a and 72b received by the receiving antennas 14a and 14b are converted into the first and second receiving side intermediate frequency conversions. Since the frequency is down-converted to different intermediate frequency bands by the local oscillators 8a and 8b having different frequencies from the parts (111a and 111b), the reference signal of the leakage component can be easily obtained by the third filter 172a and the fourth filter 172b. It can be suppressed / reduced.

  In the first and second embodiments, the millimeter wave band wireless transmission devices 9-1 and 9-2 and the millimeter wave band wireless reception devices 10-1 and 10-2 that transmit and receive millimeter wave band radio signals are provided. Although the microwave band wireless transmission / reception system provided has been described, the radio signal is not limited to the millimeter wave band, and the present invention can be applied to a microwave frequency band including the millimeter wave band.

FIG. 1 is a circuit diagram of a microwave radio transmission / reception system according to the first embodiment of the present invention. FIG. 2A is a diagram showing a frequency arrangement in the radio frequency band of the microwave band radio transmission / reception system. FIG. 2B is a diagram showing a frequency spectrum of an output on the reception side of the microwave band wireless transmission / reception system. FIG. 3 is a diagram for explaining the first and second filter functions of the receiving apparatus. FIG. 4 is a circuit configuration diagram in the case where two types of modulation signals input to the microwave band radio transmission apparatus of the microwave band radio transmission / reception system are different. FIG. 5 is a circuit configuration diagram showing a microwave band wireless transmission / reception system according to the second embodiment of the present invention. FIG. 6A is a diagram showing a frequency arrangement in a radio frequency band in the microwave radio transmission / reception system. FIG. 6B is a diagram showing a frequency arrangement in the intermediate frequency band on the receiving side. FIG. 7 is a circuit configuration diagram of a conventional microwave radio transmission / reception system. FIG. 8A is a diagram showing a frequency arrangement in the radio frequency band of the microwave radio transmission / reception system. FIG. 8B is a diagram showing a frequency spectrum of an output on the receiving side of the microwave band wireless transmission / reception system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a ... 1st satellite broadcasting receiving antenna 1b ... 2nd satellite broadcasting receiving antenna 2a, 2b ... Reference signal addition circuit 2c ... Reference signal source 3a, 3b ... Frequency conversion / transmission circuit 4a ... Transmission for vertical polarization Antenna 4b ... Transmitting antenna for horizontal polarization 5a ... First modulated signal 5b ... Second modulated signal 7a, 7b ... Frequency multiplier 8a ... Local oscillator (fLO3)
8b ... Local oscillator (fLO4)
9-1, 9-2... Microwave band radio transmitter 10-1, 10-2... Microwave band radio receiver 11a, 11b... Microwave frequency conversion circuit 12a, 12b. Circuit unit 14a ... Vertical polarization receiving antenna 14b ... Horizontal polarization receiving antenna 15a, 15b ... Output terminal 29 ... Broadcast switch 30 ... Satellite broadcast tuner 31 ... TV receiver 71a ... First intermediate frequency multiplexing Signal 71b ... Second intermediate frequency multiplexed signal 72a ... First wireless multiplexed signal 72b ... Second wireless multiplexed signal 74a ... First intermediate frequency multiplexed signal 74b ... Second intermediate frequency multiplexed signal 75a ... Output signal 75b ... Output signal 111a ... first filter 111b ... second filter 122a ... first frequency mixer 122b ... second frequency mixer 172a ... third filter 172b ... fourth filter 119a, 119b ... frequency mixer 210 ... frequency divider 201a, 201b ... frequency mixer 202a, 202b ... power combiner 301a, 301b ... frequency mixer 303a, 303b ... transmission amplifier 741a ... first IF reference signal 741b ... second IF reference Signal 742a ... first IF modulated signal 742b ... second IF modulated signal 771a ... first wireless reference signal 771b ... second wireless reference signal 772a ... first wireless modulated signal 772b ... second wireless modulated signal

Claims (8)

A first transmission-side frequency converter that up-converts the frequency of the input first modulated signal into a microwave band;
A second transmission-side frequency converter that frequency-converts the input second modulated signal into a microwave band;
A first reference signal adding unit that adds a first reference signal to the first modulated signal that is frequency up-converted to a microwave band by the first transmission-side frequency conversion unit;
Second reference signal addition for adding a second reference signal having a frequency different from that of the first reference signal to the second modulated signal frequency-converted to the microwave band by the second transmission side frequency converter And
The first radio multiplexing in which the first reference signal is added by the first reference signal adding unit to the first modulated signal whose frequency is up-converted to the microwave band by the first transmitting frequency converter. The second reference signal adding unit adds the second reference signal to the second modulation signal that is frequency up-converted to the microwave band by the first transmission unit that transmits the signal and the second transmission side frequency conversion unit. A microwave band radio transmitting apparatus comprising: a second transmitter that transmits a second radio multiplexed signal to which a signal is added with a polarization different from that of the first radio multiplexed signal. In the microwave band radio transmitter according to claim 1,
A frequency divider is provided that frequency-divides one of the first reference signal or the second reference signal to generate the other of the first reference signal or the second reference signal. A microwave band radio transmitter. In the microwave band radio transmitter according to claim 1 or 2,
The first transmission-side frequency conversion unit up-converts the frequency of the first modulated signal so as to be in a lower sideband with respect to the first reference signal,
The microwave transmission apparatus according to claim 1, wherein the second transmission-side frequency converter performs frequency up-conversion of the second modulated signal so as to be in an upper side band with respect to the second reference signal. In the microwave band radio transmitter according to any one of claims 1 to 3,
The first transmission-side frequency converter is
A first transmission-side intermediate frequency converter that upconverts the first modulated signal to an intermediate frequency band;
A first transmission-side microwave frequency conversion unit that frequency-converts the first modulation signal frequency up-converted to an intermediate frequency band by the first transmission-side intermediate frequency conversion unit into a microwave band;
The second transmission-side frequency converter is
A second transmission-side intermediate frequency converter that up-converts the second modulated signal to an intermediate frequency band;
A second transmission-side microwave frequency conversion unit that frequency-converts the second modulated signal frequency-converted to the intermediate frequency band by the second transmission-side intermediate frequency conversion unit into a microwave band;
The first reference signal adding unit adds the first reference signal to the first modulated signal frequency up-converted to an intermediate frequency band by the first transmitting intermediate frequency converting unit,
The second reference signal adding unit adds the second reference signal to the second modulated signal frequency up-converted to an intermediate frequency band by the second transmitting intermediate frequency converting unit. A microwave band radio transmitter. In the microwave band radio transmitter according to claim 4,
A frequency multiplier that generates a local oscillation signal by frequency-multiplying at least one of the first reference signal or the second reference signal;
The microwave radio transmitting apparatus according to claim 1, wherein the first and second transmitting microwave frequency converters perform frequency up-conversion based on the local oscillation signal generated by the frequency multiplier. A microwave band radio receiving apparatus that receives first and second radio multiplexed signals transmitted from the transmitting side with different polarizations, respectively,
The first radio multiplexed signal is composed of a first radio modulation signal and a first radio reference signal arranged in a frequency band above the first radio modulation signal,
The second radio multiplexed signal is composed of a second radio modulation signal and a second radio reference signal arranged in a frequency band lower than the second radio modulation signal,
A first receiver for receiving the first radio multiplexed signal;
A second receiver for receiving the second radio multiplexed signal;
A first filter for suppressing a leakage component of the second radio reference signal included in the first radio multiplexed signal received by the first receiver;
A second filter for suppressing a leakage component of the first radio reference signal included in the second radio multiplexed signal received by the second receiver;
Included in the first radio multiplexed signal based on the first radio reference signal contained in the first radio multiplexed signal in which the leakage component of the second radio reference signal is suppressed by the first filter A first reception-side frequency converter that generates a first modulated signal by frequency down-converting the first radio modulated signal,
Included in the second radio multiplexed signal based on the second radio reference signal contained in the second radio multiplexed signal in which the leakage component of the first radio reference signal is suppressed by the second filter And a second reception-side frequency converter that generates a second modulated signal by frequency down-converting the second modulated radio signal. A microwave band radio receiving apparatus that receives first and second radio multiplexed signals transmitted from the transmitting side with different polarizations, respectively,
The first radio multiplexed signal is composed of a first radio modulation signal and a first radio reference signal arranged in a frequency band above the first radio modulation signal,
The second radio multiplexed signal is composed of a second radio modulation signal and a second radio reference signal arranged in a frequency band lower than the second radio modulation signal,
A first receiver for receiving the first radio multiplexed signal;
A second receiver for receiving the second radio multiplexed signal;
A first reception-side intermediate frequency conversion unit that frequency-converts the first radio multiplexed signal received by the first reception unit into an intermediate frequency band;
A second reception-side intermediate frequency conversion unit that down-converts the second radio multiplexed signal received by the second reception unit into an intermediate frequency band;
A third filter for suppressing an intermediate frequency leakage component of the second radio reference signal included in the first intermediate frequency multiplexed signal frequency-converted to the intermediate frequency band by the first reception-side intermediate frequency conversion unit; ,
A fourth filter for suppressing an intermediate frequency leakage component of the first radio reference signal included in the second intermediate frequency multiplexed signal frequency-converted to the intermediate frequency band by the second reception-side intermediate frequency converter; ,
The first intermediate frequency reference signal corresponding to the first wireless reference signal included in the first intermediate frequency multiplexed signal, in which the intermediate frequency leakage component of the second wireless reference signal is suppressed by the third filter. To generate a first modulated signal by frequency down-converting a first intermediate frequency modulation signal corresponding to the first radio modulation signal included in the first intermediate frequency multiplexed signal. A receiving side frequency converter,
The second intermediate frequency reference signal corresponding to the second wireless reference signal included in the second intermediate frequency multiplexed signal, in which the intermediate frequency leakage component of the first wireless reference signal is suppressed by the fourth filter. Based on the second intermediate frequency modulation signal, the second intermediate frequency modulation signal corresponding to the second radio modulation signal included in the second intermediate frequency multiplexed signal is frequency down-converted to generate a second modulation signal. A microwave band radio receiving apparatus comprising: a receiving side frequency converter.   A microwave band radio transmission / reception system comprising the microwave band radio transmission apparatus according to any one of claims 1 to 5 and the microwave band radio reception apparatus according to claim 6 or 7. .

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