JP2015201679A - Multi-channel simultaneous receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a quadrature error caused by a phase error of a 90° phase shifter.SOLUTION: A multi-channel simultaneous receiver includes: a plurality of local oscillators for generating oscillation signals; a first selecting part for selecting the plurality of oscillation signals to either of outputs; a plurality of phase shift parts for accepting each of the first selecting part outputs, and outputting shifted signals which are 90° shifted inputted signals; a second selecting part for selecting the shifted signal outputs outputted by the plurality of the phase shift parts to either of outputs; a plurality of quadrature demodulation parts for inputting a reception signal, and generating a baseband signal using either one of the plurality of oscillation signals and an oscillation signal selected based on a combination of the first selected signal and the second selected signal; and a combining part for combining each of the baseband signals.

Description

  The present invention relates to a multi-channel simultaneous receiving apparatus that receives a received signal including a plurality of types of signals modulated with different information and demodulates the selected signal.

  Broadcast digitalization has been widely deployed around the world, and broadcast reception by various receivers such as home digital televisions, in-vehicle broadcast receivers, and portable information terminals has become common. Along with the diversification of reception formats, the operation of new broadcasting services that combine the features of both TV broadcasting and radio broadcasting is becoming more serious, and the number of broadcasting channels will increase rapidly in the future. It has been.

  In order to simultaneously receive and demodulate a plurality of types of signals modulated with different information, generally, the same number of tuners as the number of channels desired to be received are required. To increase.

  On the other hand, a method has been considered in which a predetermined rule is assigned at the time of frequency conversion in the analog front end so that a signal of a plurality of channels is received as a single channel signal. More specifically, a technique is disclosed in which, when a plurality of different high frequency band signals are converted into intermediate frequency band signals, the oscillation frequency is adjusted so that signals of a plurality of channels are adjacent in the intermediate frequency band ( For example, Patent Document 1). As a result, it is possible to consider a plurality of intermediate frequency band signals that have undergone frequency conversion as single-channel signals, which can be converted into digital signals by a single analog-digital converter (also referred to as an AD converter). Benefits are gained.

JP 2000-41020 A (page 6-10, FIG. 1)

  However, in the technique such as Patent Document 1, when the local oscillator is independent by two channels and there is an individual phase error due to a manufacturing error of a 90-degree phase shifter included in the local oscillator, an orthogonal error is generated. As a result, this orthogonal error cannot be compensated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a multi-channel simultaneous receiving apparatus that suppresses a quadrature error due to a phase error of a 90 ° phase shifter.

  In the multi-channel simultaneous receiving apparatus according to the present invention, a plurality of local oscillators for generating an oscillation signal, a first selection signal, a switch control unit for controlling the second selection signal, and the first selection signal Based on this, the first switching unit that switches the plurality of oscillation signals to any one of the outputs and the output of the first switching unit are input, and the signal to be shifted is obtained by shifting the phase of the input signal by 90 degrees. A plurality of phase shift units that output a signal, a second switching unit that switches each of the shifted signal outputs output from the plurality of phase shift units to any one output based on the second selection signal, and reception And an oscillation signal switched based on a combination of the first selection signal and the second selection signal among any of the plurality of oscillation signals and the output of the second switching unit. A plurality of quadrature demodulator, respectively to generate a baseband signal using, is characterized in further comprising a combining unit for combining each of the baseband signal.

  According to the present invention, a combination of an oscillation signal from the local oscillation unit and a signal obtained by shifting the phase by the phase shift unit by 90 degrees is supplied to the quadrature demodulation unit by controlling the first selection signal and the second selection signal. This makes it possible to suppress the quadrature error due to the phase error of the 90-degree phase shifter.

1 is a block diagram illustrating a configuration example of a multiple channel simultaneous reception apparatus according to a first exemplary embodiment; It is a figure which shows the relationship between the combination of the oscillation signal supply part 30, and reception quality. FIG. 3 is a block diagram illustrating a configuration example of a multiple channel simultaneous reception apparatus according to a second exemplary embodiment; It is a figure which shows the relationship between the combination of the oscillation signal supply part 31, and reception quality.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a multi-channel simultaneous receiving apparatus according to the present embodiment. Here, in order to simplify the description, the description will be made assuming that two channels are received.

  The multiple-channel simultaneous receiving apparatus according to the present embodiment includes a plurality of orthogonal demodulation units 10 and orthogonal demodulation units 11, a combining unit 20, an oscillation signal supply unit 30, an AD conversion unit 40, and a digital demodulation unit 50.

  The multi-channel simultaneous receiving apparatus combines the baseband signals generated by the plurality of orthogonal demodulation units 10 and the orthogonal demodulation unit 11 from the reception signal including a plurality of types of signals modulated with different information by the combining unit 20. At this time, the baseband signals input to the synthesis unit 20 are set to have different bands.

  The signal synthesized by the synthesizer 20 is converted into a digital signal by the AD converter 40, and digital demodulation is performed by the digital demodulator 50, whereby each digital demodulation result is obtained from each baseband signal. The digital demodulation unit 50 extracts the frequency band of the baseband signal to be digitally demodulated from the digital signal, or performs digital demodulation by suppressing the frequency band other than the frequency band of the baseband signal to be digitally demodulated. Each digital demodulation result can be obtained from a signal obtained by combining the baseband signals.

  The plurality of orthogonal demodulation units 10 and the orthogonal demodulation unit 11 input received signals including a plurality of types of signals modulated with different information, and frequency-baseband signals corresponding to the selected channels are set to the baseband frequency. A converted baseband signal is generated. At this time, the input received signal is a high frequency RF (Radio Frequency) band signal, and once converted to an IF (Intermediate Frequency) band (also referred to as an intermediate frequency band), the baseband signal is frequency converted. Do. An oscillation signal for performing this frequency conversion is supplied from the oscillation signal supply unit 30.

  The quadrature demodulator 10 temporarily converts the band component of the channel selected from the received signals input using the mixer 101 and the mixer 102 into an IF band. The mixer 101 and the mixer 102 both receive the received signal, and the oscillation signal supply unit 30 inputs the oscillation signal having the same oscillation frequency. However, the oscillation signal input to the mixer 101 and the oscillation signal input to the mixer 102 are input with an orthogonal relationship whose phase is shifted by 90 °, and the mixer 101 performs first frequency conversion into the IF band. The real component of the IF signal is output, and the imaginary part component of the first IF signal frequency-converted to the IF band is output from the mixer 102.

  The first IF signals output from the mixer 101 and the mixer 102 are input to the band limiting filter 103 and the band limiting filter 104, respectively. The band limiting filter 103 and the band limiting filter 104 pass a band including the IF band of the first IF signal and suppress other unnecessary frequency bands in order to remove unnecessary frequency components of the first IF signal. Has filter characteristics.

  The first IF signal band-limited by the band-limiting filter 103 and the band-limiting filter 104 further performs frequency conversion to the baseband band. The mixer 105 receives a signal including the real part component of the first IF signal whose band is limited, and inputs the oscillation signal from the oscillation signal supply unit 30. Similarly, the mixer 106 receives a signal including an imaginary part component of the first IF signal whose band is limited, and inputs an oscillation signal from the oscillation signal supply unit 30. However, the oscillation signal input to the mixer 105 and the oscillation signal input to the mixer 106 have an orthogonal relationship with a phase shifted by 90 °, and the mixer 105 performs the first frequency conversion to the baseband. The real part component of the first baseband signal is output from the mixer 106, and the imaginary part component of the first baseband signal frequency-converted to the baseband band is output from the mixer 106.

  The first baseband signal output from the mixer 101 and the mixer 102 is combined by the combining unit 107, and the combined first baseband signal is input to the band limiting filter 108. The band limiting filter 108 is a filter characteristic that passes a band including the baseband band of the first baseband signal in order to remove unnecessary frequency components of the first baseband signal and suppresses other unnecessary frequency bands. Have

  In this way, the quadrature demodulator 10 generates a first baseband signal from the input received signal.

  The orthogonal demodulator 11 temporarily converts the band component of the channel selected from the received signals input using the mixer 111 and the mixer 112 into an IF band. Both the mixer 111 and the mixer 112 receive the received signal, and the oscillation signal supply unit 30 inputs the oscillation signal having the same oscillation frequency. However, the oscillation signal input to the mixer 111 and the oscillation signal input to the mixer 112 are input with an orthogonal relationship whose phase is shifted by 90 °, and the mixer 111 performs frequency conversion to the IF band. The real part component of the IF signal is output, and the mixer 112 outputs the imaginary part component of the second IF signal frequency-converted to the IF band.

  The second IF signals output from the mixer 111 and the mixer 112 are input to the band limiting filter 113 and the band limiting filter 114, respectively. The band limiting filter 113 and the band limiting filter 114 pass the band including the IF band of the second IF signal in order to remove unnecessary frequency components of the second IF signal, and suppress other unnecessary frequency bands. Has filter characteristics.

  The second IF signal band-limited by the band-limiting filter 113 and the band-limiting filter 114 further performs frequency conversion to the baseband band. The mixer 115 receives a signal including a real part component of the second IF signal whose band is limited, and inputs an oscillation signal from the oscillation signal supply unit 30. Similarly, the mixer 116 receives a signal including an imaginary part component of the second IF signal whose band is limited, and inputs an oscillation signal from the oscillation signal supply unit 30. However, the oscillation signal input to the mixer 115 and the oscillation signal input to the mixer 116 have an orthogonal relationship with a phase shifted by 90 °, and the mixer 115 performs frequency conversion to the baseband band. The real part component of the baseband signal is output, and the imaginary part component of the second baseband signal frequency-converted to the baseband band is output from the mixer 116.

  The second baseband signal output from the mixer 111 and the mixer 112 is combined by the combining unit 117, and the combined second baseband signal is input to the band limiting filter 118. The band limiting filter 118 passes through a band including the baseband band of the second baseband signal to remove unnecessary frequency components of the second baseband signal, and suppresses other unnecessary frequency bands. Have

  In this way, the quadrature demodulator 11 generates a second baseband signal from the input received signal.

  The synthesizer 20 synthesizes the first baseband signal generated from the quadrature demodulator 10 and the second baseband signal generated from the quadrature demodulator 11.

  The AD conversion unit 40 receives the signal synthesized by the synthesis unit 20 and converts it into a digital signal.

  The digital demodulator 50 includes a digital filter that separates signals for two channels, and a signal component applied to the first baseband signal and a signal component applied to the second baseband signal from the digital signal from the AD converter 40. And digital demodulation separately for each channel.

  Next, the oscillation signal supply unit 30 will be described in detail. The oscillation signal supply unit 30 includes four local oscillators 301, 302, 303, and 304. In the quadrature demodulator 10, an oscillation signal (hereinafter also referred to as a first shifted signal) obtained by shifting the phase of the first oscillation signal and the first oscillation signal for frequency conversion from the RF band to the IF band by 90 ° , It is necessary to input a second oscillation signal for frequency conversion from the IF band to the baseband band and an oscillation signal obtained by shifting the phase of the second oscillation signal by 90 ° (hereinafter also referred to as a second shifted signal). There is.

  In FIG. 1, since the output signal of the local oscillator 301 is connected to the mixer 101, the first oscillator signal is generated and output by the local oscillator 301 in FIG. Similarly, since the output signal of the local oscillator 302 is connected to the mixer 105, the second oscillation signal is generated and output by the local oscillator 302 in FIG.

  Similarly, in the quadrature demodulator 11, the third oscillation signal for frequency conversion from the RF band to the IF band and the oscillation signal obtained by shifting the phase of the third oscillation signal by 90 ° (hereinafter also referred to as a third shifted signal). And a fourth oscillation signal for frequency conversion from the IF band to the baseband band and an oscillation signal obtained by shifting the phase of the fourth oscillation signal by 90 ° (hereinafter also referred to as a fourth shifted signal). Must be entered.

  Since the output signal of the local oscillator 303 is connected to the mixer 111 in FIG. 1, the third oscillation signal is generated and output by the local oscillator 303 in FIG. Similarly, since the output signal of the local oscillator 304 is connected to the mixer 115, the fourth oscillation signal is generated and output by the local oscillator 304 in FIG.

  The oscillation signal supply unit 30 switches the output signals of the four local oscillators 301, 302, 303, and 304 to any one of the four 90-degree phase shifters 321, 322, 323, and 324, and outputs the first signals. A switching unit 310 is included. The first switching unit 310 switches based on the first selection signal from the switch control unit 340. Here, it is assumed that four selection results are exclusively switched for four inputs.

  The 90-degree phase shifters 321, 322, 323, and 324 respectively shift the phase of the input oscillation signal by 90 ° and output it.

  The oscillation signal supply unit 30 is configured to input the mixer 102 (first shifted signal) and the mixer 106 (second shifted signal) with respect to the output signals of the four 90 degree phase shifters 321, 322, 323, and 324. Signal), an input of the mixer 112 (third shifted signal), and an input of the mixer 116 (fourth shifted signal), and a second switching unit 330 that switches and outputs the signal. The second switching unit 330 performs switching based on the second selection signal from the switch control unit 340. Here, it is assumed that four selection results are exclusively switched for four inputs.

  The switch control unit 340 generates a first selection signal and a second selection signal, supplies the first selection signal to the first switching unit 310, and supplies the second selection signal to the second switching unit 330. Supply.

  FIG. 2 is a diagram illustrating a relationship between a combination of the first selection signal and the second selection signal controlled by the switch control unit 340 and the orthogonal error.

  The 10-side combination is a combination on the quadrature demodulation unit 10 side, where 102 input indicates which 90-degree phase shifter is used for the input of the mixer 102 (first shifted signal), and 106 input is the mixer 106. Indicates which 90-degree phase shifter is used as the input (second shifted signal).

  The 11-side combination is a combination on the quadrature demodulation unit 11 side, where 112 input indicates which 90-degree phase shifter is used for the input (third shifted signal) of the mixer 112, and 116 input is the mixer 116. Indicates which 90-degree phase shifter is used as the input (fourth shifted signal).

  For example, if the input 102 is 321, it indicates that the 90-degree phase shifter 321 is used as the input (first shifted signal) of the mixer 102. That is, the output of the local oscillator 301 is input to the 90-degree phase shifter 321, and the output of the 90-degree phase shifter 321 is input to the mixer 102 as the first shifted signal. Further, if 106 inputs are 90 degree phase shifters 322, the remaining 112 inputs are 323 or 324 as 90 degree phase shifters, and if 112 inputs are 90 degree phase shifters 323, 116 inputs are 324, If 112 inputs are 90 degree phase shifter 324, 116 inputs will be 323.

  That is, there are 12 combinations of the first selection signal and the second selection signal controlled by the switch control unit 340.

  The 10-side quadrature error is a quadrature error associated with the combination of the input of the mixer 102 (first shifted signal) and the input of the mixer 106 (second shifted signal). This is because the quadrature error caused by the first oscillated signal and the first shifted signal and the quadrature error caused by the second oscillated signal and the second shifted signal are combined to determine how many quadratures in the quadrature demodulator 10 Indicates whether an error has occurred. For example, the orthogonal error when 102 inputs are 321 and 106 inputs are 322 is shown as DEG10_1.

  The 11-side quadrature error is a quadrature error associated with the combination of the input of the mixer 112 (third shifted signal) and the input of the mixer 116 (fourth shifted signal). This is because the quadrature error caused by the third oscillating signal and the third shifted signal and the quadrature error caused by the fourth oscillated signal and the fourth shifted signal are combined to determine how many quadratures the quadrature demodulator 11 has. Indicates whether an error has occurred. For example, the orthogonal error when 112 inputs are 323 and 116 inputs are 324 is shown as DEG11_1.

  The 10-side reception quality is the reception quality associated with the combination of the input of the mixer 102 (first shifted signal) and the input of the mixer 106 (second shifted signal). For example, the reception quality when the 102 input is 321 and the 106 input is 322 is indicated as ERR10_1.

  The 11-side reception quality is the reception quality associated with the combination of the input of the mixer 112 (third shifted signal) and the input of the mixer 116 (fourth shifted signal). For example, the reception quality when 112 inputs are 323 and 116 inputs are 324 is indicated as ERR10_1.

  Here, the reception quality indicates the signal quality of the reception signal of each selected channel. For example, information indicating a CN ratio, information indicating a MER (modulation error ratio), information indicating a packet error rate, information indicating a bit error rate, or the like is obtained from the digital demodulator 50.

  The CN ratio represents a ratio between a carrier and noise, and for example, a frequency spectrum is obtained and a level of a corresponding band of a broadcast wave is compared with a level of a surrounding band. is there. The CN ratio information obtained in this way can be used as signal quality.

  MER (modulation error ratio) represents how much the constellation at the time of digital demodulation deviates from the ideal point. For example, the distance between the ideal point of the constellation pattern and the received signal point is obtained from the digitally demodulated signal, and is obtained by averaging for a certain period or moving average. The MER thus obtained can correspond to a value proportional to the CN ratio, and can be signal quality.

  The packet error rate indicates how much error correction could not be performed among the transmitted packets. For example, when a received signal is digitally modulated and a block code such as a Reed-Solomon code is used, the number of packets corrected when the signal is decoded by the error correction circuit of the digital demodulation unit can be obtained. The error rate can be calculated. The packet error rate information obtained in this way can be used as signal quality.

  The bit error rate indicates how many error bits are transmitted among the transmitted bits. When the code convolved during signal modulation is Viterbi-decoded by the error correction circuit of the digital demodulator, the Viterbi decoding method is a method of selecting plausible data, so it is not certain whether the error has been corrected. Therefore, the Viterbi-decoded data is re-encoded as correct, and the re-encoded data is compared with the data before and after Viterbi decoding, whereby the bit error rate can be easily obtained. The bit error rate information obtained in this way can be used as signal quality.

  The switch control unit 340 first selects the first combination of the first selection signal and the second selection signal to determine an appropriate combination by looking at which combination results in a good reception quality. The combination of the signal and the second selection signal is determined, and the first selection signal and the second selection signal that are the combination are set.

  As a procedure for determining an appropriate combination, for each of the combinations of the first selection signal and the second selection signal, the respective reception qualities when set one by one are acquired, stored in association with the combination, all When the acquisition of the respective reception qualities for the combinations is completed, an appropriate combination is determined from all the combinations.

  At this time, for example, if there is a difference in required reception quality between the channel selected by the orthogonal demodulation unit 10 and the channel selected by the orthogonal demodulation unit 11, the reception quality on the channel side that is required to have good reception quality. The combination may be determined giving priority to the good one. For example, when the channel selected by the quadrature demodulator 10 is related to the viewing provision of the user, such as terrestrial television broadcasting, when the demodulated data is decoded into the video signal, the viewing noise such as block noise is adversely affected. If the reception quality is not so high, and the result demodulated by the quadrature demodulator 11 is not as good as the reception quality of the terrestrial television broadcast, the combination having the best reception quality of the quadrature demodulator 10 is selected first. Then, the combination having the best reception quality may be selected from the remaining combinations on the orthogonal demodulation unit 11 side.

  Thus, by controlling the combination of the oscillation signal from the local oscillation unit and the signal obtained by shifting the phase by the phase shift unit by 90 degrees and supplying it to the quadrature demodulation unit, a 90 degree phase shifter It is possible to control to a combination that suppresses the quadrature error due to the phase error.

  In addition, with regard to control for determining an appropriate combination among all combinations of the first selection signal and the second selection signal, for example, when the user is not viewing, the user's viewing is prioritized. Thus, an appropriate combination for the selected channel can be determined. When the user is not viewing, channel selection is performed for all receivable channels such as channel search, and an appropriate combination of receivable channels is determined and stored. In this way, when the user selects a desired channel, it can be set to an appropriate combination that has been previously determined for the desired channel, and can be received in a more optimal state. There is an effect that it becomes possible.

Embodiment 2. FIG.
In the first embodiment, as the two-channel simultaneous receiving apparatus, the orthogonal demodulation unit 10 and the orthogonal demodulation unit 11 use the oscillation frequency of the oscillation signal used when performing frequency conversion from the RF band to the IF band, and the IF band. The oscillation frequency of the oscillation signal used for frequency conversion to the baseband band is set independently. In the present embodiment, a mode is shown in which the oscillation frequency of an oscillation signal used when performing frequency conversion from the IF band to the baseband band is made common.

  FIG. 3 is a configuration diagram of the multiple-channel simultaneous receiving apparatus according to the present embodiment. Here, in order to simplify the description, the description will be made assuming that two channels are received. The components having the same reference numerals as those in the first embodiment are the same as those described in the first embodiment, and thus the description thereof is omitted.

  The oscillation signal supply unit 31 includes three local oscillators 301, 302, and 303. Further, the first switching unit 311 performs switching based on the first selection signal from the switch control unit 341. Here, it is assumed that three selection results are exclusively switched for three inputs. The second switching unit 331 performs switching based on the second selection signal from the switch control unit 341. Here, it is assumed that three selection results are exclusively switched for three inputs.

  In this embodiment, the mixer 105 and the mixer 115 are commonly connected to the output signal of the local oscillator 302. Further, the mixer 106 and the mixer 116 are connected to the output of the fourth switching unit 331 that is shared. That is, the second oscillation signal and the fourth oscillation signal are the same signal. Similarly, the second shifted signal and the fourth shifted signal indicate the same signal.

  FIG. 4 is a diagram illustrating a relationship between the orthogonal error and the combination of the first selection signal and the second selection signal controlled by the switch control unit 341 of the oscillation signal supply unit 31 according to the present embodiment. The difference between the combination of the first selection signal and the second selection signal in Embodiment 1 shown in FIG. 2 and the diagram showing the relationship between the orthogonal errors is that the input to the mixer 106 and the input to the mixer 116 are different. It is common.

  In this way, by sharing the oscillation frequency of the oscillation signal used when performing frequency conversion from the IF band to the baseband band, the number of local oscillators can be reduced, and the number of switching units can be reduced. There is a new effect.

10, 11 Quadrature demodulation unit 301, 302, 303, 304 Local oscillator 310 First switching unit 321, 322, 323, 324 Phase shifter 330 Second switching unit 340 Switch control unit 20 Synthesis unit

Claims (7)

A plurality of local oscillators for generating an oscillation signal;
A switch control unit for controlling the first selection signal and the second selection signal;
A first switching unit configured to switch the plurality of oscillation signals to any one output based on the first selection signal;
A plurality of phase shift units that input each of the outputs of the first switching unit and output a shifted signal obtained by shifting the phase of the input signal by 90 degrees;
A second switching unit that switches each of the shifted signal outputs output by the plurality of phase shift units to any one output based on the second selection signal;
A reception signal is input, and one of the plurality of oscillation signals and an oscillation signal switched based on a combination of the first selection signal and the second selection signal among the outputs of the second switching unit. A plurality of orthogonal demodulation units each generating a baseband signal using,
A multi-channel simultaneous receiving apparatus comprising: a combining unit that combines the baseband signals. An AD converter that converts the signal combined by the combiner into a digital signal;
A digital demodulation unit that digitally demodulates the digital signal and outputs reception quality information indicating reception quality related to each of the baseband signals;
2. The multi-channel simultaneous receiving apparatus according to claim 1, wherein the switch control unit controls the first selection signal and the second selection signal based on the reception quality information. Each of the plurality of orthogonal demodulation units includes a first frequency conversion unit that performs frequency conversion from a high frequency band to an intermediate frequency band, and a second frequency conversion unit that performs frequency conversion from the intermediate frequency band to a baseband frequency band. ,
3. The multi-channel simultaneous receiving apparatus according to claim 1, wherein the oscillation signal and the shifted signal input to each of the second frequency converters are the same. 4. The reception quality is information based on the CN ratio of the received signal,
A CN ratio calculation unit for obtaining a CN ratio from a demodulation result of the digital demodulation unit;
3. The switch control unit according to claim 2, wherein the switch control unit detects and sets a combination in which the CN ratio is optimal among all combinations of the first selection signal and the second selection signal. 4. A multi-channel simultaneous receiving apparatus according to item 3. The received quality is information based on a modulation error ratio of the received signal,
A modulation error ratio calculation unit for obtaining a modulation error ratio from a demodulation result of the digital demodulation unit;
3. The switch control unit according to claim 2, wherein the switch control unit detects and sets a combination in which the modulation error ratio is optimal among all combinations of the first selection signal and the second selection signal. Item 4. The multi-channel simultaneous receiving device according to Item 3. The reception quality is information based on a packet error rate of the received signal,
A packet error rate calculation unit for obtaining a packet error rate from the demodulation result of the digital demodulation unit;
3. The switch control unit according to claim 2, wherein the switch control unit detects and sets a combination in which the packet error rate is optimal among all combinations of the first selection signal and the second selection signal. Item 4. The multi-channel simultaneous receiving device according to Item 3. The reception quality is information based on the bit error rate of the received signal,
A bit error rate calculation unit for obtaining a bit error rate from a demodulation result of the digital demodulation unit;
3. The switch control unit according to claim 2, wherein the switch control unit detects and sets a combination in which the bit error rate is optimal among all combinations of the first selection signal and the second selection signal. Item 4. The multi-channel simultaneous receiving device according to Item 3.

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