JP2006050052A - High frequency communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carrier configuration for preventing interference from other carrier in the case of extracting a base band signal in a subcarrier communication system used for a broadband communication system. <P>SOLUTION: An occupied band is divided into a plurality of carriers and a guard band including a frequency bandwidth similar to a carrier frequency bandwidth is inserted between the carriers. Or a configuration using double side band is adopted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wireless communication system that operates from an RF band to a millimeter wave band, and more particularly to a communication system that realizes high-speed and large-capacity communication.

  In recent years, the amount of information consumed by individuals continues to increase year by year as information technology develops. In the information communication field, the situation is the same in the wireless communication field, and the increase in the amount of information used by individuals in digital data communication is significant. To cope with this increasing communication traffic, the communication speed of the communication system used is increased. The demand is very large. In the field of wireless communication, a plurality of mobile communication systems represented by cellular telephones and wireless local area networks (LANs) have been developed and serviced, and data communication speeds there have been studied. For example, second-generation cellular telephones such as GSM (Global System for Mobile Communications), one of the mobile communication systems, has a data communication speed of about 14.4 kbps, and the third-generation mobile communication developed as a successor system. In the system (IMT200: International Mobile Telecommunication 2000), a 2Mbps communication speed was included as a specification to achieve a communication speed of about 50 times. Furthermore, in a wireless communication system that is desired in the future, it is considered that a communication line of 1 Gbps or more equivalent to wired communication is required.

  Since the communication speed is generally proportional to the occupied communication bandwidth, it is necessary to widen the communication band in order to realize high-speed communication. Although it depends on the signal modulation multiplicity of the configured communication system, the current standard communication system requires a frequency band of 1 GHz to 2 GHz to realize a communication capacity of 1 GBps. On the other hand, in heterodyne communication that converts a communication band into a high-frequency carrier wave, the ratio of the signal bandwidth to the carrier frequency is defined as a ratio band. When using normal circuit technology, this is because of the ease of realizing high-frequency components. The specific bandwidth is preferably about 10% or less. In order to realize higher-speed communication than these, it is necessary to consider the trade-off relationship between the bandwidth and the specific bandwidth rather than simply taking a wide bandwidth. For example, in order to realize a communication system with a communication speed exceeding 2 Gbps, a communication bandwidth of about 2 GHz is required. From consideration of the corresponding bandwidth, microwaves with a carrier frequency of 20 GHz or higher are required. It is necessary to set the band to the millimeter wave band.

  Conversely, if a high-frequency circuit with a narrow band characteristic with a practical bandwidth ratio of less than a few percent is used, and a communication bandwidth of about 10% is secured, the communication bandwidth is defined as multiple subcarriers. It is effective to divide the channels into different narrow-band channels and form one wide communication band as a whole. This is called a multicarrier system.

  With respect to a communication system in which a plurality of users represented by mobile communication is connected, several communication methods are used depending on the communication channel configuration method and the dynamic assignment method of communication paths to users. Typical examples are frequency division multiple access (FDMA), time division multiple access (TDMA), and code division multiple access (CDMA). Among these, frequency division multiplexing (FDD), which divides the occupied band into multiple frequency bands, bundles channels with different frequencies called subcarriers into a single carrier (carrier). The so-called subcarrier multiplex (SCM) system is known. This is an example of a practical multi-carrier scheme.

Conventionally, regarding the handling of subcarriers in such an SCM system, each subcarrier is frequency-converted into a carrier frequency band and power is combined as one carrier (Patent Document 1), and the carrier is a low frequency fundamental frequency (base A method (Patent Document 2) that decomposes into subcarriers after frequency conversion into a band signal) has been shown. When the frequency is converted to a baseband signal and then decomposed into subcarriers or signal processing is performed, the analog signal is converted into a digital signal in addition to the analog signal processing, and the signal processing is performed on the digital signal processing circuit. There was something to do (Patent Document 2, Patent Document 3).
International Publication No. 96/18249 Pamphlet Japanese Patent Laid-Open No. 11-17644 JP 2002-57595 A

  The demand for increased communication capacity can be addressed by expanding the occupied bandwidth and further multiplexing. However, a high-frequency component or a high-frequency circuit that can operate in a specific band of 10% or more (having so-called broadband characteristics) has a problem that the configuration becomes complicated and expensive. In general, the requirement for communication quality against noise and interference becomes stricter as multiplexing progresses, and there is a problem that the probability of transmission error increases even in an environment where the same level of noise and interference occurs. Becomes more prominent in a communication system having broadband characteristics.

  On the other hand, in the current wireless communication system, a plurality of modulation methods are used, and the methods differ depending on regions. There is a lack of device compatibility between different systems, and communication devices corresponding to each communication system must be developed. Further, even on the side where the communication device is used, there is a problem that when using a plurality of communication systems, it is necessary to have a communication device corresponding to each method. In particular, this problem becomes conspicuous when a high-frequency circuit is configured by an analog system, and there is a problem that a high-frequency analog circuit corresponding to each system must be used.

  For the problems as described above, the present invention can secure a relatively wide communication bandwidth while taking a specific bandwidth of 10% or less for high-speed and large-capacity communication, and a system using different modulation / demodulation methods. It is an object of the present invention to provide a communication device that can cope with a simple high-frequency circuit configuration. Another object is to supply this apparatus at a low cost.

  According to the present invention, in a subcarrier multiplex high-frequency communication apparatus that includes a plurality of signal carriers in an occupied band and uses a frequency of 80 MHz or more as a carrier wave, a single sideband signal is used for each signal carrier, A system in which a plurality of carriers are arranged with a frequency interval equal to or greater than the frequency bandwidth of the signal carrier between each signal carrier. Or it is set as the communication system which uses a double-sideband for a carrier.

  In addition, the band is limited so that the ratio band of the occupied band transmitted and received by wireless communication to the carrier frequency is 10% or less.

  Further, the occupied bandwidth of a plurality of subcarriers included in the occupied band is 20 MHz or less. Alternatively, the carrier is configured to be 80 GHz or more.

  According to the present invention, in a subcarrier multiplex communication system using one sideband, a frequency interval equal to or greater than the frequency bandwidth of a signal carrier is taken between a plurality of carriers in an occupied band (a guard band is inserted). Thus, when frequency conversion is performed to extract the baseband signal, it is possible to prevent the signal after conversion of another carrier from overlapping the signal band, and a guard band having the same frequency bandwidth as the carrier signal is provided. Therefore, a sufficient modulation system can be ensured even if the characteristics of a filter for removing an image from a high-frequency signal and a low-pass filter for extracting a baseband signal are relaxed. Further, when extracting a plurality of carriers from the multicarrier, the baseband signal circuit can be shared by changing the local oscillation frequency according to each carrier.

  On the other hand, by limiting the band ratio of the occupied band transmitted and received by wireless communication to the carrier frequency to 10% or less, it becomes easy to manufacture each element used in the analog high frequency circuit. In addition, by making the occupied bandwidth of multiple subcarriers included in the occupied band 20 MHz or less, various high-frequency devices that are already in practical use can be used for baseband circuits or intermediate frequency band circuits, resulting in low cost. A communication system can be configured. Further, by setting the carrier wave to 80 GHz or higher, a communication system can be constructed without affecting the communication system currently used at 80 GHz or lower.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment)
FIG. 1 is a circuit block diagram showing a communication apparatus used in the present invention. On the transmission side, a transmission signal processing circuit 12 having the same configuration is used for a plurality of transmission data 11, and the transmission signal is modulated by digital signal processing. Transmission data 11 represents analog data such as audio and video. The transmission signal processing circuit 12 converts an analog / digital converter (ADC), a digital signal processing circuit (DSP) that performs signal processing on the digital signal output of the ADC, and a digital signal output of the DSP into a transmission signal. It consists of a digital-to-analog converter (DAC). Here, in the digital signal processing performed by the DSP, in addition to the modulation processing according to each communication method, a compensation effect for distortion generated in a transmission amplifier circuit or a transmission path, that is, a spatial propagation path in the case of a wireless communication system is incorporated. Signal processing may also be performed. Thereafter, the output of each transmission signal processing circuit is arranged in each channel in the transmission signal by the power combining circuit 13, and one wide band transmission signal is combined as a whole. As a synthesis method at this time, frequency conversion by frequency conversion or the like is used. Furthermore, the transmission signal is amplified by the driver amplifier (DRV) in a lump, and after the power level is made sufficient, unnecessary spurious is removed by the band-pass filter (BPF), and then the heterodyne method by the non-linear circuit (MIX) is used. The frequency is converted to the carrier frequency. Furthermore, spurious generated by the frequency conversion is removed by BPF, and transmission is performed by transmitting this carrier wave from an antenna (ANT). At this time, the local oscillation power used for frequency conversion is obtained by multiplying the output of the voltage controlled oscillator (VCO) by an integer multiple by a frequency multiplex and selecting the desired frequency in the output by BPF. .

  On the other hand, on the receiving side, the carrier frequency received by the antenna (ANT) is frequency-converted to a low frequency by a heterodyne method, further amplified by an amplifier (AMP), and then each channel is input to the received signal processing circuit 15 by the power distribution circuit 16. Separate to become a signal. The local oscillation power used for the frequency conversion of the carrier wave is generated by multiplying the output of the voltage controlled oscillator (VCO) by the frequency of the multiplier. For removing spurious, BPF is appropriately used as in the transmission side. Furthermore, power distribution also uses down-conversion by frequency conversion, and each channel is converted to the same frequency band so that it can be processed by an intermediate frequency circuit or baseband circuit having a common configuration. Next, the signal of each channel is sampled by the ADC having the same configuration and demodulated by the DSP. The demodulated signal is output as a received signal after each data is reconstructed by a subsequent DAC.

  The present invention relates to a configuration of a broadband signal using a plurality of signal channels. Details of the configuration of the wideband signal will be described with reference to signal carrier arrangement on the frequency axis with reference to FIGS. 4, 5, and 6. FIG. 4 schematically shows the frequency relationship on the receiving side in the first invention. A carrier signal 1 corresponding to a wideband signal is composed of a set of a plurality of subcarriers 2 and is transmitted over a space on a carrier wave. The carrier signal 1 received by the antenna is frequency-converted to an intermediate frequency signal 3 and then separated into subcarrier signals (first data 4, second data 5, and 1024 data 6). This is performed by the power distributor 16 in FIG. 3 to be described later.

  FIG. 5 shows a frequency arrangement showing the first aspect of the present invention, and the carrier uses a single sideband system. Each carrier is arranged with a frequency interval equal to or greater than that of the carrier, and a plurality of carriers are used to realize wideband characteristics. The carrier structure frequency-converted to the intermediate frequency by this arrangement is shown by IF / RF on the right side of FIG. This conceptual diagram is the same for the intermediate frequency band and the carrier band. When an arbitrary carrier CHn is converted to a low frequency from this carrier and extracted, the local oscillation frequency indicated by LOn and the signal are input to the frequency mixer, and the output is a low frequency band having a cut-off frequency corresponding to the frequency band. This is achieved by passing a pass filter (LPF). For example, when the high frequency signal (CHn) 34 is taken out in FIG. 5, the local oscillation power (LOn) corresponding to the low frequency side of the high frequency signal (CHn) 34 and the carrier signal are input to the frequency mixer, thereby obtaining the baseband. A signal (CHn) 31 is obtained. At this time, the high-frequency signal (CHn-1) located on both sides of the high-frequency signal (CHn) and the return signal after frequency conversion of the high-frequency signal (CHn + 1) are the high-frequency side ((CHn-1) + (CHn-1) of the baseband signal. +1)) 32, it will not interfere with the baseband signal (CHn) 31. The same is true for other signals, so signal interference is reduced in this system.

  On the other hand, FIG. 6 shows a frequency arrangement showing the second aspect of the invention, and the carrier uses a double sideband communication system. A guard band of 4% or more with respect to the carrier bandwidth is inserted between the carriers, and a plurality of carriers are used in order to realize broadband characteristics as a whole. The carrier configuration converted to the intermediate frequency by this arrangement is shown by IF / RF on the right side of FIG. This conceptual diagram is the same for the intermediate frequency band and the carrier band. When CHn is converted to a low frequency from this carrier, the local oscillation frequency indicated by LOn and the signal are input to the frequency mixer, and the output is a low-pass filter having a cutoff frequency corresponding to the frequency band. Realized by passing (LPF). When the high frequency signal (CHn) 45 is extracted, the baseband signal (CHn) 41 is obtained by inputting the local oscillation power (LOn) corresponding to the center frequency of the high frequency signal (CHn) 45 and the carrier signal to the frequency mixer. obtain. At this time, the high-frequency signal (CHn-1) located on both sides of the high-frequency signal (CHn) and the return signal after frequency conversion of the high-frequency signal (CHn + 1) are the high-frequency side ((CHn-1) + (CHn-1) of the baseband signal. +1)) 42, the baseband signal (CHn) 41 is not interfered. The same is true for other signals, so signal interference is also reduced in this system.

  FIG. 1 is a block diagram particularly when the carrier wave is 80 GHz or higher, and does not include a transmission amplifier on the transmission side and a low noise amplifier on the reception side. This is because it is difficult to obtain an amplifier having sufficient capability at a low cost in a frequency band of 80 GHz or higher, and a circuit that does not use an amplifier when realizing broadband communication at a carrier frequency of 80 GHz or higher as in the present invention. This is because the configuration was desired. The local oscillation source used for frequency conversion uses a voltage controlled oscillator (VCO) and a frequency multiplier. This is also because it is difficult to obtain a sufficient output in the VCO in the frequency band of 80 GHz or higher, and the double output of the VCO is used as the local oscillation power as a practical circuit configuration. Furthermore, at 80 GHz or higher, the wavelength of the carrier wave becomes shorter, so the antenna can be made smaller. That is, even if a plurality of antennas are used, the apparatus does not become large. Therefore, in the present invention, the transmitting and receiving antennas are independent.

  FIG. 2 illustrates the power combining circuit 13 on the transmission side shown in FIG. 1 in more detail. Each signal is appropriately arranged in the transmission channel by the upmixer 17 by frequency conversion using oscillation sources (OSC1, OSC2, OSC3,...) Having different frequencies as local oscillation power. After the frequency conversion, a BPF is inserted in order to remove spurious, and a transmission signal 21 is formed by combining the power as one transmission band after power combining. This power combining is configured by a filter-configured multiplexer, Wilkinson type power combiner, branch line type coupler, and directional coupler. A low-pass filter (LPF) is inserted before the ADC of the data input unit and after the DAC in order to reduce aliasing distortion.

  On the other hand, FIG. 3 is a block diagram illustrating in detail the power distribution circuit 16 on the receiving side shown in FIG. Power distribution is performed by a power distribution unit 20 configured by a coupler, a Wilkinson type power distributor, and the like, and after channel separation by a downmixer 19, the power is input to a reception signal processing circuit. At this time, in power distribution using a coupler or a Wilkinson type power divider, a wide band received signal is input to each received signal processing circuit. In the figure, OSC1, OSC2, and OSC3 are sources of local oscillation power for the frequency conversion circuit. In addition, by configuring the power distribution unit 20 with a demultiplexer having a filter configuration, the separated signal can be a single narrowband signal. Furthermore, the function of the power distribution unit 20 may be realized by frequency conversion using a mixer. The signal processing unit has a dual configuration as shown in Fig. 2 and removes aliasing distortion at the time of frequency conversion by LPF, digitization of the signal by ADC, signal processing by DSP, digital / analog conversion by DAC, and DAC processing by LPF The aliasing distortion is removed.

(Experimental example 1)
An experimental example for the first invention will be described. The subcarrier frequency band is 20 MHz in total including the 19 MHz signal part and the upper and lower 0.5 MHz guard bands. The subcarrier frequency band ranges from 2 to a maximum of 1024, and a total width of about 40 MHz to 20.48 GHz. The configuration is such that it can be taken. The ADC and DAC used in the transmission signal processing circuit and the reception signal processing circuit both have 16-bit resolution, and the sampling frequency is 200 MHz. A low-pass filter having a cut-off frequency of 20 MHz was used for band limitation on the input side of the ADC and the output side of the DAC.

  On the transmission side, the QPSK modulation is performed by the DSP in the transmission signal processing circuit, and the frequency dependency and power dependency of the amplitude, and the frequency dependency and power dependency of the phase are considered so as to compensate for the nonlinearity of the transmission path. The compensation process was performed. After this signal was converted to an analog signal by DAC, a 20 MHz wide carrier and a 20 MHz guard band were alternately arranged by frequency conversion to form a channel. Here, since the heterodyne method is adopted, the power at intervals of 40 MHz generated by the synthesizer is used as the local oscillation power. The total number of channels was 512, and the total bandwidth as a communication system was 20.48 GHz. This was once converted into an intermediate frequency by 40 GHz local oscillation power, and other than the upper sideband was removed by a filter. Furthermore, a carrier signal of 292 GHz to 312.48 GHz was formed by using the local oscillation power of 252 GHz, up-converting by a heterodyne method, and taking the upper sideband. This signal was sent from the radiator by the waveguide horn to the space. The local oscillation power of 252 GHz is obtained by multiplying the 14 GHz signal by 18.

  On the receiving side, it is also received by a radiator using a waveguide horn, down-converted to an intermediate frequency with a local oscillation power of 252 GHz, further down-converted with a local oscillation power of 40 GHz, and then each local oscillation power at intervals of 40 MHz. The channel signal was extracted. Thereafter, the original signal was reproduced by passing through a reception signal processing circuit using ADC, DSP, and DAC.

  Actually, 18 MHz is used for 4 carriers and 80 MHz band including guard band, 1 channel is used for transmission of audio signal and various additional information data, and the remaining 3 channels are used for video signal transmission. In addition to QPSK, ASK, FSK, QAM, etc. can be digitally modulated by changing DSP software in addition to QPSK, and π / 4 shift QPSK modulation used in domestic mobile phone systems and overseas mobile phones GMSK modulation used in the system and 3 / 8π offset 8PSK modulation used in the EDGE system were also possible.

  When the input baseband signal is a digital signal, the ADC in the transmission side signal processing circuit can be omitted, and similarly, the DAC in the reception side signal processing circuit can be omitted. Further, if the channel configuration is determined, it is possible to separate the digital signal input / output path and the analog signal input / output path to make the signal processing circuit configuration different.

(Experimental example 2)
FIG. 7 is a block diagram showing a second experimental example of the present invention. A carrier wave of 5.2 GHz was used, a transmission amplifier 23 was arranged on the transmission side, and a low noise amplifier 24 was arranged on the reception side. The frequency band of the subcarrier is 5 MHz, and the configuration is such that an effective signal band of 2 to a maximum of 64 subcarriers and a maximum of 320 MHz as a whole can be obtained. The ADC and DAC used in the transmission signal processing circuit and the reception signal processing circuit had a resolution of 14 bits and a sampling frequency of 120 MHz. A low-pass filter with a cutoff frequency of 5 MHz was used for band limitation on the input side of the ADC and the output side of the DAC.

  On the transmission side, 16QAM modulation is performed by a DSP in the transmission signal processing circuit, and the frequency dependence of amplitude and power dependence, and the frequency dependence of phase so as to compensate for nonlinearity of the transmission path, particularly distortion of the transmission amplifier. And compensation processing considering power dependence was performed. After this signal was converted to an analog signal by DAC, a guard band having a width of 5 MHz was arranged by frequency conversion to form a channel. In this experimental example, the total number of channels was 8, and the total bandwidth was 80 MHz. This was up-converted by a heterodyne method using a local oscillation power of 5.2 GHz, and a carrier signal of 5.2 GHz to 5.28 GHz was formed by taking an upper side band. This signal was sent to the space from the helical antenna.

  On the receiving side, the signal was similarly received by a helical antenna, amplified by a low noise amplifier 24, and then down-converted to a baseband signal having a band of 80 MHz with a local oscillation power of 5.2 GHz. From there, the signal was distributed by a power distribution circuit using a Wilkinson power distributor and input to each received signal processing circuit. In each received signal processing circuit, after sampling by ADC, signals corresponding to channels at intervals of 5 MHz are extracted from the signals in the 80 MHz band by digital filter processing, and the demodulation operation is similarly performed by digital processing.

(Experimental example 3)
A third experimental example will be described using a block diagram similar to FIG. 2.4 GHz was used as a carrier wave of the carrier, a transmission amplifier 23 was arranged on the transmission side, and a low noise amplifier 24 was arranged on the reception side. The frequency band of the subcarrier is 2 MHz, and the configuration is such that an effective signal band of 2 to a maximum of 64 subcarriers and a maximum of 128 MHz as a whole can be obtained. The ADC and DAC used in the transmission signal processing circuit and the reception signal processing circuit have a resolution of 12 bits and a sampling frequency of 100 MHz. A low-pass filter with a cutoff frequency of 2 MHz was used for band limitation on the input side of the ADC and the output side of the DAC.

  On the transmission side, in the transmission signal processing circuit, two-phase PSK modulation is performed by the DSP, and the frequency dependence and power of the amplitude are adjusted so as to compensate for nonlinearity of the transmission path, particularly distortion of the transmission amplifier and fading characteristics in the propagation path. Compensation processing was performed in consideration of the dependence, frequency dependence of the phase, and power dependence. This signal was converted to an analog signal by a DAC and then placed in a channel at 2 MHz intervals by frequency conversion. At this time, each channel is arranged using frequency conversion by a mixer, and is arranged directly in the 2.4 GHz band without using an intermediate frequency to form a transmission carrier. At this time, double-sided waves are used. That is, the bandwidth after frequency conversion was 4 MHz. In this experimental example, the total number of channels was 8, and the total bandwidth was 32 MHz. This signal was sent to the space from the helical antenna.

  Similarly, the signal was received by the helical antenna on the receiving side, amplified by the low noise amplifier 24 and input to the power distributor 16. In the power distribution unit 16, each channel is converted to a baseband signal by frequency conversion and input to each received signal processing circuit. In each received signal processing circuit, after sampling by ADC, demodulation operation is performed by digital filter processing, and the original signal is reproduced.

  Although the input signal is not particularly described in the above description, it may be an audio signal, an analog video signal, or a signal modulated by another communication system. However, the frequency band must be within the bandwidth that can be taken by the subcarrier of the high-frequency communication device of the present invention.

  The present invention is useful for a high-speed and large-capacity communication system in the RF frequency band to the millimeter wave band. In particular, since a plurality of modulation schemes can be transmitted and received by the same device, it is compatible with communication systems already in practical use and useful for large-capacity communication.

Circuit block diagram of high-frequency communication apparatus showing the present invention 1 is a block diagram showing a transmission side signal processing circuit and a power combiner in the circuit block of the high-frequency communication apparatus of FIG. FIG. 1 is a block diagram showing a reception side signal processing circuit and a power distribution unit in the communication system block of FIG. Conceptual diagram showing the arrangement of carrier signals on the frequency axis The figure which shows the frequency arrangement | positioning method of the subcarrier using the single sideband which shows this 1st invention The figure which shows the frequency arrangement | positioning method of the subcarrier using the double sideband wave which this 2nd invention shows Circuit block diagram showing a second example of the present invention

Explanation of symbols

1 carrier signal 2 subcarrier 3 intermediate frequency signal 4 first data 5 second data 6 1024 data 11 transmission data 12 transmission signal processing circuit 13 power combining circuit 14 reception data 15 reception signal processing circuit 16 power distribution circuit 17 upmixer 18 Power combiner 19 Downmixer 20 Power distributor 21 Transmit signal 22 Receive signal 23 Transmit amplifier 24 Low noise amplifier 25 Transmit / receive selector switch 31 Baseband signal (CHn)
32 Conversion signal (CHn-1 + CHn + 1)
33 Low-pass filter 34 High-frequency signal (CHn)
35 High-frequency signal (CHn-1)
36 High-frequency signal (CHn + 1)
37 Local signal (LOn)
38 Local signal (LOn-1)
39 Local signal (LOn + 1)
41 Baseband signal (LSB + USB)
42 Conversion signal (CHn-1 + CHn + 1)
43 High-frequency signal (CHn)
44 High-frequency signal (CHn-1)
45 Low sideband (LSB)
46 High frequency band (USB)
47 Local signal (LOn)
48 Local signal (LOn-1)
49 Carrier spacing

Claims (5)

In a high-frequency communication system that uses a frequency division multicarrier method including a plurality of signal carriers in an occupied band and performs wireless communication with a carrier frequency of 80 MHz or more,
Use one sideband signal for each said signal carrier,
Furthermore, in the arrangement | positioning in the said occupation band of the said signal carrier, the frequency interval more than the frequency bandwidth which the said signal carrier occupies is taken between each said signal carriers, The high frequency communication system characterized by the above-mentioned. In a high-frequency communication system that uses a frequency division multicarrier method including a plurality of signal carriers in an occupied band and performs wireless communication with a carrier frequency of 80 MHz or more,
A high-frequency communication system using a double-sideband signal for each of the signal carriers. The ratio band of the occupied band used by the high-frequency communication system to the carrier frequency is 10% or less,
The high-frequency communication system according to claim 1 or 2, wherein a plurality of signal carriers are included in the occupied band and radio communication is performed at a carrier frequency of 80 MHz or more. The high-frequency communication system according to claim 1 or 2, wherein a plurality of signal carriers are included in an occupied band, the occupied bandwidth of the signal carrier is 20 MHz or less, and wireless communication is performed with a carrier frequency of 80 MHz or more. . The high-frequency communication system according to claim 1 or 2, wherein a plurality of signal carriers are included in an occupied band and radio communication is performed at a carrier frequency of 80 GHz or more.

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