Transmitter, receiver, communication system, transmitting method, and receiving method

Abstract

To provide a transmitter capable of achieving wireless communication that uses a communication signal in which carrier signals are multiplexed in an amplitude value direction.SOLUTION: A transmitter includes: an acquisition unit that acquires multiple information series, which are bit series; an encoder that uses an error correcting code to encode each of the multiple information series into a code series, which is a soft-value data series; an amplifier that multiplies each of the multiple code series by a default real number amplitude value; an adder that adds together the multiple code series multiplied by the real number amplitude value to generate a communication signal in which multiple carrier signals are multiplexed in an amplitude value direction; and a transmitting unit that modulates the generated communication signal and transmits the modulated communication signal.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a transmitter, a receiver, a communication system, a transmitting method, and a receiving method. [Background technology]

[0002] In wireless communication, the communication capacity is increasing, so the exhaustion of frequency resources is becoming a problem. It is difficult to increase the communication capacity in a communication system once it has been constructed.

[0003] Patent Document 1 discloses a wireless superimposed transmission method using an error correcting code. The method of Patent Document 1 uses a plurality of first signals and a second signal. An error correcting code is applied to the plurality of first signals, in which one or both ends are superimposed with adjacent signals in the frequency domain. The second signal is further superimposed on one of the superimposed bands, which is a band in which the plurality of first signals are superimposed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-109370 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the method of Patent Document 1, communication capacity is increased by multiplexing signals in the frequency direction. However, in the method of Patent Document 1, there is a limit to signal multiplexing depending on the frequency bandwidth. If signals can be multiplexed in the amplitude value direction, communication capacity can be increased without depending on the frequency bandwidth.

[0006] An object of the present disclosure is to provide a transmitter, a receiver, a communication system, a transmission method, and a reception method that are capable of realizing wireless communication using a communication signal in which a carrier signal is multiplexed in the amplitude value direction. [Means for solving the problem]

[0007] A transmitter according to one embodiment of the present disclosure includes an acquisition unit that acquires a plurality of information sequences, which are bit sequences; an encoder that uses an error correcting code to encode each of the plurality of information sequences into a code sequence, which is a soft-value data sequence; an amplifier that multiplies each of the plurality of code sequences by a predetermined real amplitude value; an adder that adds together the plurality of code sequences multiplied by the real amplitude value to generate a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; and a transmission unit that modulates the generated communication signal and transmits the modulated communication signal.

[0008] A receiver according to one embodiment of the present disclosure includes a receiving unit that receives a communication signal in which multiple carrier signals are multiplexed in the amplitude value direction, a decoder that uses an error correcting code to decode an information sequence, which is a bit sequence, from a code sequence to be decoded, which is a soft-value data sequence derived from the communication signal, a re-encoder that re-encodes the decoded information sequence if the decoded information sequence is not the one to be received, a multiplier that multiplies the re-encoded code sequence by a predetermined real amplitude value to generate a replica signal, a subtractor that updates the code sequence to be decoded by subtracting the replica signal from the code sequence to be decoded, and an output unit that outputs the information sequence to be received if the decoded information sequence is the one to be received.

[0009] In a transmission method according to one aspect of the present disclosure, a plurality of information series, which are bit series, are obtained, and each of the plurality of information series is encoded using an error correcting code into a code series, which is a soft-value data series, and each of the plurality of code series is multiplied by a predetermined real amplitude value, and the plurality of code series multiplied by the real amplitude value are added to each other to generate a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction, the generated communication signal is modulated, and the modulated communication signal is transmitted.

[0010] In a receiving method according to one aspect of the present disclosure, a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction is received, and an information sequence, which is a bit sequence, is decoded using an error correcting code from a code sequence to be decoded, which is a soft-value data sequence derived from the communication signal, and if the decoded information sequence is not the one to be received, the decoded information sequence is re-encoded, the re-encoded code sequence is multiplied by a predetermined real amplitude value to generate a replica signal, the replica signal is subtracted from the code sequence to be decoded to update the code sequence to be decoded, and if the decoded information sequence is the one to be received, the information sequence to be received is output. Effect of the Invention

[0011] According to the present disclosure, it is possible to provide a transmitter, a receiver, a communication system, a transmission method, and a reception method that can realize wireless communication using a communication signal in which a carrier signal is multiplexed in the amplitude value direction. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a conceptual diagram illustrating an example of a configuration of a communication system according to the present disclosure. [Diagram 2] 2 is a block diagram showing an example of a configuration of a transmitter provided in a communication system according to the present disclosure. FIG. [Diagram 3] 2 is a block diagram showing an example of a configuration of a receiver included in a communication system according to the present disclosure. FIG. [Figure 4] FIG. 2 is a conceptual diagram for explaining an example of signal duplication in the present disclosure. [Diagram 5] FIG. 1 is a conceptual diagram for explaining an example of encoding in the present disclosure. [Figure 6] FIG. 13 is a conceptual diagram for explaining an example of decoding in the present disclosure. [Figure 7] FIG. 2 is a conceptual diagram for explaining an example of signal multiplexing in the present disclosure. [Figure 8] 10 is a flowchart for explaining an example of an operation of a transmitter included in a communication system in the present disclosure. [Figure 9]11 is a flowchart for explaining an example of an operation of a receiver included in a communication system in the present disclosure. [Figure 10] 2 is a block diagram showing an example of a configuration of a transmitter according to the present disclosure. FIG. [Figure 11] 10 is a flowchart for explaining an example of an operation of a transmitter in the present disclosure. [Figure 12] 1 is a block diagram showing an example of a configuration of a receiver according to the present disclosure. [Figure 13] 11 is a flowchart for explaining an example of an operation of a receiver in the present disclosure. [Figure 14] FIG. 2 is a block diagram showing an example of a hardware configuration for executing processes according to each embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiment for carrying out the present disclosure will be described with reference to the drawings. In this disclosure, the drawings used in the description of each embodiment relate to one or more embodiments. In addition, the elements included in each drawing may apply to one or more embodiments. The embodiments described below are limited in a technically preferable manner for carrying out the present disclosure, but the scope of the disclosure is not limited to the following. In all the drawings used in the description of the following embodiments, the same reference numerals are used for similar parts unless there is a special reason. In the following embodiments, repeated description of similar configurations and operations may be omitted. The direction of the arrows in the drawings is an example, and does not limit the direction of signals, etc. In the following embodiments, symbols indicating vectors are written in normal alphabets.

[0014] (First embodiment) First, a communication system according to a first embodiment will be described with reference to the drawings. The communication system according to this embodiment multiplexes signals in the amplitude value direction. A transmitting station (transmitter) of the communication system according to this embodiment multiplexes a code sequence encoded with an error correcting code in the amplitude value direction. Noise is added to a code sequence in which a plurality of code sequences are multiplexed in the communication path. A receiving station (receiver) decodes an information sequence to be received from the received code sequence.

[0015] First, the principle of signal multiplexing in this embodiment will be described. In digital wireless communication, an error correction code is used to reduce the error rate of an information sequence caused by noise or the like added in a communication path. In an error correction code, encoding and decoding are paired. An error correction code is a code for decoding an information sequence from a composite signal of a noise sequence added to a code sequence in a communication path. From another perspective, an error correction code is a code for extracting an information sequence from a composite signal that is doubled with a code sequence and a noise sequence. In this embodiment, a line is multiplexed by superimposing a carrier signal in which an information sequence is encoded, instead of a noise signal.

[0016] The decoding error rate of the error correcting code is determined by the power value of the noise. Therefore, even when two carrier signals (code sequences) are superimposed, the decoding performance is determined by the power value of the superimposed carrier signals. If two carrier signals are superimposed and decoded by the error correcting code, the decoding error rate is high in the carrier signal with the smaller power value. When an information sequence decoded by the error correcting code is decoded by a decoder of the same error correcting code, an information sequence in which all errors are corrected or an information sequence containing some errors is obtained. In addition, if the modulation method is known, a replica signal can be generated. Another carrier signal is obtained by subtracting the replica signal from the received carrier signal. Another information sequence can be obtained by decoding this carrier signal. In this way, multiplexing of lines is possible. In this embodiment, lines are multiplexed by multiplexing the code sequence (carrier signal) encoded by error correction in the power direction (amplitude value direction).

[0017] (composition) FIG. 1 is a conceptual diagram showing an example of a configuration of a communication system 1 in the present disclosure. The communication system 1 includes a transmitter 11 and multiple receivers 15-1 to n (n is a natural number). The transmitter 11 is installed in a transmitting station. Each of the multiple receivers 15-1 to n is installed in a receiving station. In the following, when the multiple receivers 15-1 to n are not distinguished from one another, they are referred to as receiver 15. In the communication system 1, communication is performed using an existing communication method. There is no particular limitation on the communication band used by the communication system 1. In FIG. 1, an information sequence is referred to as information, and a code sequence is referred to as code.

[0018] The transmitter 11 has a wireless communication function. As long as the transmitter 11 can wirelessly communicate with the multiple receivers 15-1 to n, there are no particular limitations on the network band or modulation method used by the transmitter 11. The transmitter 11 transmits a communication signal on which multiple carrier signals are superimposed, to the multiple receivers 15-1 to n. The wireless signal includes a carrier signal directed to each of the multiple receivers 15-1 to n.

[0019] The transmitter 11 obtains an information sequence directed to each of the multiple receivers 15-1 to n. The information sequence includes information directed to each of the multiple receivers 15-1 to n. The transmitter 11 encodes the information sequence for each of the multiple receivers 15-1 to n using an error correcting code. The transmitter 11 encodes the information sequence u1 into a code sequence v1 using a first error correcting code. The transmitter 11 encodes the information sequence u2 into a code sequence v2 using a second error correcting code. Furthermore, the transmitter 11 encodes the information sequence u1 into a code sequence v2 using an n-th error correcting code. n Let v be the code sequence. n The first error correcting code, the second error correcting code, . . . , the n-th error correcting code may be different from each other, or at least any of them may be the same.

[0020] The transmitter 11 multiplies a plurality of code sequences coded using an error correction code by a predetermined real amplitude value. The transmitter 11 multiplexes the code sequences (carrier signals) multiplied by the real amplitude value in the power direction (amplitude direction). The real amplitude value may be different for each code sequence, or may be the same for at least one of the code sequences. The transmitter 11 transmits a communication signal composed of the multiplexed carrier signals to a plurality of receivers 15-1 to 15-n.

[0021] The communication signal includes a first carrier signal, a second carrier signal, ..., an n-th carrier signal. The first carrier signal includes a code sequence v1 into which an information sequence u1 is encoded. The information sequence u1 includes information intended for the receiver 15-1. The second carrier signal includes a code sequence v2 into which an information sequence u2 is encoded. The information sequence u2 includes information intended for the receiver 15-2. The n-th carrier signal includes an information sequence u n The encoded code sequence v n Contains the information sequence u n includes information directed to the receiver 15-n. For example, an application example is assumed in which a second carrier signal, ..., n-th carrier signal are superimposed on a first carrier signal used in a backbone communication network. There is no particular limitation on the backbone communication network as long as it is a network using a wireless line. For example, terrestrial digital broadcasting is exemplified as an example of a backbone communication network.

[0022] The multiple receivers 15-1 to n have a wireless communication function. As long as the multiple receivers 15-1 to n can wirelessly communicate with the transmitter 11, there are no particular limitations on the network band or modulation method used by the multiple receivers 15-1 to n. The multiple receivers 15-1 to n receive wireless signals transmitted from the transmitter 11. The wireless signals include carrier signals that are the target of reception by each of the multiple receivers 15-1 to n.

[0023] The multiple receivers 15-1 to n receive a communication signal transmitted from the transmitter 11. The communication signal includes multiple multiplexed carrier signals. In the communication path between the transmitter 11 and the receiver 15, noise is added to the communication signal. Furthermore, in the communication path, the strength (real amplitude value) of each carrier signal fluctuates. Each of the multiple receivers 15-1 to n decodes an information sequence directed to the respective receiver 15. A specific method for decoding the information sequence from the carrier signal will be described later. There are no particular limitations on the output destination or use of the decoded information sequence.

[0024] The receiver 15-1 decodes an information sequence u1XORe1 from a communication signal composed of multiplexed carrier signals (code sequences). The information sequence u1XORe1 includes a decoding error e1. The receiver 15-1 outputs information including the information sequence u1 to be received. For the receiver 15-1, a signal that is decoded into an information sequence other than the information sequence u1 can be regarded as noise.

[0025] The receiver 15-2 decodes an information sequence u1XORe1 from a communication signal composed of multiplexed carrier signals (code sequences). The information sequence u1XORe1 includes a decoding error e1. The receiver 15-2 re-encodes the decoded information sequence u1XORe1 and multiplies it by a predetermined real amplitude value to generate a replica signal. The receiver 15-2 subtracts the generated replica signal from the multiplexed carrier signals (code sequences) to generate a code to be decoded. The receiver 15-2 decodes an information sequence u2XORe2 from the code to be decoded. The information sequence u2XORe2 includes a decoding error e2. The multiple receivers 15-2 output information including the information sequence u2 to be received.

[0026] The receiver 15-n decodes an information sequence u1XORe1 from a communication signal composed of multiplexed carrier signals (code sequences). The information sequence u1XORe1 includes a decoding error e1. The receiver 15-n re-encodes the decoded information sequence u1XORe1 and multiplies it by a predetermined real amplitude value to generate a replica signal. The receiver 15-n subtracts the generated replica signal from the multiplexed carrier signals (code sequences) to generate a code to be decoded. The receiver 15-n decodes an information sequence u2XORe2 from the code to be decoded. The information sequence u2XORe2 includes a decoding error e2. The receiver 15-n decodes the information sequence u n The re-encoding, replica signal generation, subtraction, and decoding are repeated until the information sequence u n Output information including:

[0027] [Transmitter] Next, the transmitter 11 included in the communication system 1 will be described with reference to the drawings. Fig. 2 is a block diagram showing an example of the configuration of the transmitter 11 in the present disclosure. The transmitter 11 has an acquisition unit 111, an encoder 112, an amplifier 113, an adder 115, and a transmission unit 117. Fig. 2 shows the main configuration for performing processing according to this embodiment. Fig. 2 does not show all of the configuration for realizing the transmission function of the transmitter 11.

[0028] The acquisition unit 111 acquires an information sequence u (n is a natural number) transmitted to each of the multiple receivers 15-1 to 15-n. The information sequence u is a bit sequence composed of {0, 1}. In the following, the information sequence transmitted to the receiver 15-i is referred to as u i (i is a natural number between 1 and n). There is no particular limitation on the method of acquiring an information sequence by the acquiring unit 111. For example, the acquiring unit 111 acquires an information sequence u input via an input device (not shown). For example, the acquiring unit 111 acquires an information sequence u including information to be transmitted that is stored in a storage device (not shown).

[0029] The encoder 112 uses an error correcting code φ to convert an information sequence u to be transmitted to each of the multiple receivers 15-1 to 15-n into a code sequence v of sequence length L. The conversion of the information sequence u into a code sequence v using the error correcting code φ is expressed by the following equation 1. [Number 1] φ(u) = v (1) The code sequence v is a soft-value data sequence composed of {-1, 1}. The encoder 112 encodes the information sequence u i Let v be the code sequence. i Convert to.

[0030] The error correction code φ may be the same for each information sequence u, or may be different for each information sequence u. There is no particular limitation on the error correction code used by the encoder 112. For example, a block code, a convolutional code, or a concatenated code can be applied as the error correction code. For example, the block code includes a CRC (Cyclic Redundancy Check) code and a BCH (Bose-Chaudhuri-Hocquenghem) code. In addition, the block code includes a Reed-Solomon code and an LDPC (Low Density Parity Check) code. For example, the convolutional code includes a convolutional coding-Viterbi decoding method and a turbo code.

[0031] The amplifier 113 amplifies a signal in a frequency band used for communication. The amplifier 113 amplifies the signal in a frequency band used for communication. i The real amplitude value a set for each i Then, the code sequence v i For example, the amplifier 113 amplifies the code sequence v i The amplifier 113 is arranged for each code sequence v i Real amplitude value a for each i With a gain according to i Amplify the real amplitude value a i is the code sequence v i The code sequence v i The number of times may be different for each

[0032] The adder 115 adds the multiple carrier signals (code sequences) amplified by the amplifier 113 to generate a communication signal in which the multiple carrier signals are superimposed in the amplitude value direction. i The amplified code sequence a i v i Adding these, we get the code sequence a i v i The communication signal is generated by superimposing the above in the amplitude value direction.

[0033] The transmitting unit 117 modulates the communication signal generated by the adder 115. The transmitting unit 117 transmits the modulated communication signal. Note that a modulation unit (not shown) may be provided to modulate the communication signal. There is no particular limitation on the modulation method of the communication signal transmitted from the transmitting unit 117. For example, the signal transmitted from the transmitting unit 117 is modulated by a binary phase shift keying (BPSK) method. For example, the signal transmitted from the transmitting unit 117 may be modulated by a quadrature phase shift keying (QPSK) method. For example, the signal transmitted from the transmitting unit 117 may be modulated by a differential phase shift keying (DPSK) method. The communication signal transmitted from the transmitting unit 117 is received by each of the multiple receivers 15-1 to n.

[0034] [Receiver] Next, the receiver 15 included in the communication system 1 will be described with reference to the drawings. Fig. 3 is a block diagram showing an example of the configuration of the transmitter 11 in the present disclosure. The receiver 15 has a receiving unit 151, a decoder 152, a re-encoder 153, a multiplier 155, a subtractor 156, a corrector 157, and an output unit 159. Fig. 3 shows the main configuration for performing processing according to this embodiment. Fig. 3 does not show all of the configuration for realizing the receiving function of the receiver 15.

[0035] The receiver 151 receives a communication signal transmitted from the transmitter 11 via the communication path 13. The received communication signal (code sequence) corresponds to the code sequence to be decoded. i ) is the real amplitude value A i In the following, the real amplitude value A i It is assumed that the rate of change of the amplitude values ​​of the multiple carrier signals included in the communication signal is the same in the communication path. That is, the code sequence v i The real amplitude value A i Code sequence v for i+1 The real amplitude value A i+1 and the code sequence v at the transmitter 11 i The real amplitude value of a i Code sequence v for i+1 The real amplitude value of a i+1 Furthermore, a noise sequence n is added to the code sequence received by the receiver 151.

[0036] The decoder 152 decodes the information sequence from the code sequence to be decoded using the error correcting code. The decoder 152 converts the code sequence v+n to which the noise sequence n is added into an information sequence uXORe using the error correcting code ψ. XOR stands for exclusive OR. The information sequence uXORe includes a decoding error e. The decoding of the information sequence uXORe using the error correcting code ψ is expressed by the following equation 2. [Number 2] ψ(v+n)=uXORe (2) The noise sequence n is a real-valued sequence. + represents the addition of real values.

[0037] In the first decoding, the decoder 152 decodes the code sequence to be decoded with the error correcting code ψ1 to obtain an information sequence u1XORe1 including a decoding error e1. The information sequence u1XORe1 indicates the exclusive OR of the information sequence u1 and the decoding error e1. If the information sequence u1 is to be received, the decoder 152 outputs the decoded information sequence u1XORe1 to the corrector 157. If the information sequence u1 is not to be received, the decoder 152 outputs the decoded information sequence u1XORe1 to the re-encoder 153. In the second or subsequent i-th decoding, the decoder 152 decodes the code sequence to be decoded with the error correcting code ψ i Decoding with,decoding error e i Information sequence u containing i XORe i We obtain the information sequence u i is the object of reception, the decoder 152 receives the decoded information sequence u i XORe i is output to the corrector 157. i If not, the decoder 152 receives the decoded information sequence u i XORe i to the re-encoder 153. The decoder 152 repeats the decoding of the code sequence to be decoded until the information sequence to be received is obtained.

[0038] The re-encoder 153 encodes the information sequence uXORe that was not the target of reception. The re-encoder 153 re-encodes the information sequence uXORe with an error correcting code φ, as shown in the following equation 3. [Number 3] φ(uXORe)=v+N (3) N is the noise sequence generated by the decoding error e. By subtracting Equation 3 from Equation 1, the noise sequence N remains, but the code sequence v can be eliminated.

[0039] Here, if the code sequence v'+n', which is the sum of a code sequence v' obtained by encoding another information sequence u' with an error correcting code φ' and a noise sequence n', is replaced with the noise sequence n, Equation 2 can be expressed as Equation 4 below. [Number 4] ψ(v+v'+n')=uXORe' (4) The following equation 5 represents the re-encoding of the information sequence uXORe′ using the error correcting code φ. [Number 5] φ(uXORe')=v+v'+N' (5) From equations 1 and 5, the relationship shown in equation 6 below can be derived. [Number 6] φ(uXORe')-φ(u)=v'+N' (6) When the code sequence v'+N' on the right-hand side of equation 6 is decoded with the error correcting code ψ', the information sequence uXORe'' is decoded as shown in equation 7 below. [Number 7] ψ(v'+N')=uXORe'' (7) In this way, multiple information sequences are obtained by multiplexing multiple code sequences (carrier signals) encoded with error correcting codes. In other words, lines are multiplexed by multiplexing multiple code sequences encoded with error correcting codes.

[0040] The re-encoder 153 repeatedly re-encodes the information sequence including the decoding error until the decoder 152 obtains the information sequence to be received. In the first re-encoding, the re-encoder 153 encodes the information sequence u1XORe1 including the decoding error e1 into a code sequence v1+n1 using the error correcting code φ1. In the second or subsequent i-th re-encoding, the re-encoder 153 encodes the information sequence u1XORe1 including the decoding error e1 into a code sequence v1+n1 using the error correcting code φ i Using the above, the decoding error e i Information sequence u containing i XORe i Let v be the code sequence. i +n i Encode it as follows.

[0041] The multiplier 155 multiplies the real amplitude value after fluctuations in the communication path by the code sequence output from the re-encoder 153 to generate a replica signal. In the first multiplication, the multiplier 155 multiplies the real amplitude value A1 after fluctuations in the communication path by the code sequence v1+n1 to generate a replica signal A1(v1+n1). In the second or subsequent i-th re-encoding, the multiplier 155 multiplies the real amplitude value A1 after fluctuations in the communication path by the code sequence v1+n1 to generate a replica signal A1(v1+n1). i Let v be the code sequence. i +ni Multiplying by this to get replica signal A i (v i +n i Multiplier 155 repeats the generation of replica signals until decoder 152 obtains the information sequence to be received.

[0042] The subtractor 156 subtracts the replica signal from the code sequence to be decoded, and updates the code sequence to be decoded with the code sequence after the subtraction. In the first subtraction, the subtractor 156 subtracts the replica signal A1(v1+n1) from the received multiplexed code sequence. In the second or subsequent i-th re-encoding, the subtractor 156 subtracts the previous replica signal A1(v1+n1) from the received multiplexed code sequence. 1-1 (v 1-1 +n 1-1 The subtractor 156 subtracts replica signal A1(v1+n1) from the code sequence from which the subtraction of v1(v1+n1) has been performed. The subtractor 156 repeats the subtraction of the replica signal until the decoder 152 obtains the information sequence to be received.

[0043] The corrector 157 corrects the decoding error of the information sequence to be received. i XORe i Decoding error e i By correcting the received information sequence u i We obtain the information sequence u i XORe i Decoding error e i If the corrector 157 is not corrected, the corrector 157 may be omitted.

[0044] The output unit 159 receives the information sequence u i The information sequence u i XORe i Decoding error e i If not corrected, the output unit 159 outputs the decoding error e i Information sequence u containing i XORe i The information sequence u i There is no particular limitation on the output destination of the information sequence u i is the information sequence u iThe output is directed to a system or device that uses the

[0045] [Dualization] Next, the duplication of the line in this disclosure will be described. The multiplexing of the error correcting code is performed by soft decision decoding in order to multiplex the code sequence in the amplitude value direction. In the transmitting station, two types of bit information sequences composed of {0, 1} are converted into two code sequences. The k1-bit information sequence u1 is converted into a code sequence v1 of sequence length L1 by the error correcting code φ1. The k2-bit information sequence u2 is converted into a code sequence v2 of sequence length L2 by the error correcting code φ2. The error correcting code φ1 and the error correcting code φ2 may be the same or different.

[0046] When an error correcting code ψ1 corresponding to the error correcting code φ1 is used, the code sequence v1+n1 to which the noise sequence n1 is added is decoded in the communication path to obtain an information sequence u1XORe1. The coding rate of the error correcting code φ1 is k1 / L1. When an error correcting code ψ2 corresponding to the error correcting code φ2 is used, the code sequence v2+n2 to which the noise sequence n2 is added is decoded in the communication path to obtain an information sequence u2XORe2. The coding rate of the error correcting code φ2 is k2 / L2. The sum of the code sequence a1v1 obtained by multiplying the code sequence v1 by the real amplitude value a1 and the code sequence a2v2 obtained by multiplying the code sequence v2 by the real amplitude value a2 is the code sequence a1v1+a2v2. However, the real amplitude value a1 is greater than the real amplitude value a2. The transmitter 11 transmits a communication signal including the code sequence a1v1+a2v2 to the communication path.

[0047] A noise sequence n is added to the communication signal (code sequence a1v1+a2v2) transmitted from the transmitter 11 (transmitting station) in the communication path. The receiver 15 (receiving station) receives the code sequence expressed by the following equation 8. [Number 8] A1v1+A2v2+n···(8) A1 corresponds to a real amplitude value a1 that is increased or attenuated in the communication path. A2 corresponds to a real amplitude value a2 that is increased or attenuated in the communication path. A1 and A2 are assumed to satisfy the relationship of the following formula 9. [Number 9] A2 / A1=a2 / a1 (9) The code sequence A1v1+A2v2+n shown in Equation 8 can be regarded as a composite signal in which the noise sequence A2v2+n is added to the code sequence A1v1. Decoding of the code sequence A1v1+A2v2+n by the error correcting code ψ1 is expressed by the following Equation 10. [Number 10] ψ1(A1v1+A2v2+n)=u1XORe1···(10) e1 is a decoding error.

[0048] When the right side of Equation 10 is re-encoded using the error correcting code φ1, it is expressed as Equation 11 below. [Number 11] φ1(u1XORe1)=v1+n1 (11) If A1 is known, the code sequence shown on the right side of the following equation 12 can be obtained by subtracting the right side of equation 11 multiplied by the real amplitude value A1 from the code sequence A1v1+A2v2+n expressed in equation 8. [Number 12] A1v1+A2v2+n-A1(v1+n1)=A2v2+n-A1n1...(12) The code sequence A2v2+n-A1n1 on the right-hand side of Equation 12 can be regarded as the code sequence A2v2 encoded with the error correcting code φ2 to which a noise sequence n-A1n1 has been added.

[0049] Decoding of the code sequence A2v2+n-A1n1 using the error correcting code ψ2 is expressed by the following equation 13. [Number 13] ψ2(A2v2+n-A1n1)=u2XORe2···(13) As described above, the information sequence u1 including the decoding error e1 can be obtained from equation 10. Moreover, the information sequence u2 including the decoding error e2 can be obtained from equation 13. That is, according to the technique of this embodiment, different information can be transmitted from a single transmitter 11 (transmitting station) to two receivers 15 (receiving stations) by using the same communication signal.

[0050] FIG. 4 is a conceptual diagram showing an example of a line duplicated by the technique of the present disclosure. The transmitter 11 transmits a code sequence (communication signal) in which a code sequence (code 1) and a code sequence (code 2) are superimposed in the amplitude value direction. The code sequence (code 1) is a first carrier signal in which an information sequence (information 1) is encoded. The information sequence (information 1) includes information addressed to the receiver 15-1. The code sequence (code 2) is a second carrier signal in which an information sequence (information 2) is encoded. The information sequence (information 2) includes information addressed to the receiver 15-2. The communication signal is a signal in which a second carrier signal is superimposed in the amplitude value direction on a first carrier signal.

[0051] Receiver 15-1 receives a communication signal (code sequence) transmitted from transmitter 11. Receiver 15-1 decodes an information sequence (information 1) from the received communication signal (code sequence). For receiver 15-1, the decoded information sequence (information 1) is the object of reception. In this way, receiver 15-1 decodes the communication signal (code sequence) transmitted from transmitter 11 into the information sequence (information 1) to be received.

[0052] The receiver 15-2 receives a communication signal (code sequence) transmitted from the transmitter 11. The receiver 15-2 decodes an information sequence (information 1) from the received communication signal (code sequence). For the receiver 15-2, the decoded information sequence (information 1) is not the reception target. The receiver 15-2 re-encodes the decoded information sequence (information 1). The receiver 15-2 multiplies the real amplitude value of the code sequence (code 1) at the time of reception by the re-encoded code sequence to generate a replica signal. The receiver 15-2 subtracts the replica signal from the received code sequence to calculate the code sequence to be decoded. The receiver 15-2 decodes an information sequence (information 2) from the code sequence to be decoded. For the receiver 15-2, the decoded information sequence (information 2) is the reception target. With this procedure, the receiver 15-2 decodes the information sequence (information 2) to be received from the communication signal (code sequence) transmitted from the transmitter 11.

[0053] [Multiplexing] Next, line multiplexing in the present disclosure will be described. Fig. 5 and Fig. 6 are conceptual diagrams for explaining line multiplexing in the present disclosure. Fig. 5 is a conceptual diagram for explaining encoding in the transmitter 11. Fig. 6 is a conceptual diagram for explaining decoding in the receiver 15. An example of n-fold line multiplexing (n is a natural number) will be described below. In Fig. 5 and Fig. 6, subscripts such as i and j are added to distinguish individual signals (i and j are natural numbers between 1 and n).

[0054] In FIG. 5, the acquisition unit 111 acquires an information sequence u i The encoder 112 obtains the obtained information sequence u by using the error correction code φ1. i The sequence length L i The code sequence v i Convert to the error correcting code φ i is the information sequence u i It may be the same for each information sequence u i The amplifiers 113 (ξ1 to ξ n ) is the real amplitude value a i With the amplification factor of , the code sequence v i Let a be the code sequence a i v i The adder 115 amplifies the code sequence v1 to the code sequence v n Regarding the amplified code sequence a i v i The transmitter 117 sends out a communication signal (code sequence) represented by the sum of the code sequences expressed by the following equation 14 to the communication path 13. [Number 14] TIFF2025024817000002.tif9150 The communication signal (code sequence) expressed by Equation 14 is a signal in which a plurality of carrier signals (code sequences) are multiplexed in the amplitude value direction.

[0055] 6, a receiving unit 151 receives a communication signal (code sequence) transmitted from a transmitter 11 via a communication path 13. The receiving unit 151 receives a communication signal (code sequence) expressed by the following equation 15. [Number 15] TIFF2025024817000003.tif9150 The code sequence of the above equation 15 corresponds to the code sequence to be decoded.

[0056] The receiver 151 receives a real amplitude value a i is the real amplitude value A i The receiver 15 receives the code sequence v i The real amplitude value A i Code sequence v for i+1 The real amplitude value A i+1 and the code sequence v at the transmitter 11 i The real amplitude value of a i Code sequence v for i+1 The real amplitude value of a i+1 The ratio is assumed to satisfy the following equation 16. [Number 16] In the following TIFF2025024817000004.tif10150, the real amplitude value A i Assume that is known.

[0057] The code sequence to be decoded of the above equation 15 can be transformed into a code sequence to be decoded expressed by the following equation 17. [Number 17] TIFF2025024817000005.tif9150 As shown in the following equation 18, the decoder 152 decodes the information sequence from the code sequence to be decoded in the above equation 17 by using the error correcting code ψ1. [Number 18] TIFF2025024817000006.tif9150 In equation 18, e1 is a decoding error.

[0058] As shown in the following equation 19, the re-encoder 153 re-encodes the information sequence u1XORe1 on the right-hand side of equation 18 with the error correcting code φ1. [Number 19] TIFF2025024817000007.tif6150The code sequence v1+n1 on the right-hand side of the above equation 19 contains a noise sequence n1.

[0059] The multiplier 155 multiplies the real amplitude value A by the code sequence v1+n1 on the right side of the above equation 19. i to generate a replica signal A1(v1+n1).

[0060] The subtractor 156 subtracts the replica signal A1(v1+n1) from the code sequence of the equation 17. As a result, the code sequence to be decoded of the following equation 20 is obtained. [Number 20] TIFF2025024817000008.tif9150The above formula 20 corresponds to the code sequence to be decoded.

[0061] The decoder 152 decodes the code sequence to be decoded, expressed by the above equation 20, with the error correcting code ψ2. As a result, an information sequence u2XORe2 is obtained.

[0062] The re-encoder 153 re-encodes the information sequence u2XORe2 using the error-correcting code φ2, converting it into a code sequence v2+n2. The multiplier 155 multiplies the real amplitude value A2 by the code sequence v2+n2 to generate a replica signal A2(v2+n2). When the same calculation is repeated, when i=j, the code sequence becomes the following formula 21, and the information sequence u i XORe i is obtained. [Number 21] TIFF2025024817000009.tif11150 Receiver 15 (receiving station) further repeats the calculation to obtain u n XORe n It is possible to obtain n information sequences up to

[0063] The corrector 157 corrects the information sequence u n XORe n By correcting the error, the received information sequence u k (k is a natural number between 1 and n).

[0064] FIG. 7 is a conceptual diagram showing an example of a line multiplexed (triple) by the method of the present disclosure. The transmitter 11 transmits a code sequence (communication signal) in which a code sequence (code 1), a code sequence (code 2), and a code sequence (code 3) are superimposed in the amplitude value direction. The code sequence (code 1) is a first carrier signal in which an information sequence (information 1) is encoded. The information sequence (information 1) includes information for the receiver 15-1. The code sequence (code 2) is a second carrier signal in which an information sequence (information 2) is encoded. The information sequence (information 2) includes information for the receiver 15-2. The code sequence (code 3) is a third carrier signal in which an information sequence (information 3) is encoded. The information sequence (information 3) includes information for the receiver 15-3.

[0065] Receiver 15-1 receives a communication signal (code sequence) transmitted from transmitter 11. Receiver 15-1 decodes an information sequence (information 1) from the received communication signal (code sequence). For receiver 15-1, the decoded information sequence (information 1) is the target of reception. In this way, receiver 15-1 decodes the communication signal (code sequence) transmitted from transmitter 11 into the information sequence (information 1) to be received.

[0066] The receiver 15-2 receives a communication signal (code sequence) transmitted from the transmitter 11. The receiver 15-2 decodes an information sequence (information 1) from the received communication signal (code sequence). For the receiver 15-2, the decoded information sequence (information 1) is not the target of reception. The receiver 15-2 re-encodes the decoded information sequence (information 1). The receiver 15-2 multiplies the real amplitude value of the code sequence (code 1) at the time of reception by the re-encoded code sequence to generate a replica signal. The receiver 15-2 subtracts the replica signal from the received code sequence to calculate the code sequence to be decoded. The receiver 15-2 decodes the information sequence (information 2) to be received from the code sequence to be decoded. For the receiver 15-2, the decoded information sequence (information 2) is the target of reception. In this manner, the receiver 15-2 decodes the information sequence (information 2) to be received from the communication signal (code sequence) transmitted from the transmitter 11.

[0067] The receiver 15-3 receives a communication signal (code sequence) transmitted from the transmitter 11. The receiver 15-3 decodes an information sequence (information 1) from the received communication signal (code sequence). The receiver 15-3 does not want to receive the decoded information sequence (information 1). The receiver 15-3 re-encodes the decoded information sequence (information 1). The receiver 15-3 multiplies the real amplitude value of the code sequence (code 1) at the time of reception by the re-encoded code sequence to generate a replica signal. The receiver 15-3 subtracts the replica signal from the received code sequence to calculate the code sequence to be decoded. The receiver 15-3 decodes an information sequence (information 2) to be received from the code sequence to be decoded. The receiver 15-3 does not want to receive the decoded information sequence (information 2). The receiver 15-3 re-encodes the decoded information sequence (information 2). The receiver 15-3 multiplies the re-encoded code sequence by the real amplitude value of the code sequence (code 2) at the time of reception. The receiver 15-3 subtracts a replica signal from the code sequence to be decoded at that time to calculate a new code sequence to be decoded. The receiver 15-3 decodes an information sequence (information 3) from the code sequence to be decoded. For the receiver 15-3, the decoded information sequence (information 3) is the object to be received. With this procedure, the receiver 15-3 decodes the information sequence (information 3) to be received from the communication signal (code sequence) transmitted from the transmitter 11.

[0068] (operation) Next, the operation of the communication system 1 in this embodiment will be described with reference to the drawings. In the following, the operations of the transmitter 11 and the receiver 15 included in the communication system 1 will be described individually.

[0069] [Transmitter] Fig. 8 is a flowchart showing an example of the operation of the transmitter 11 in the present disclosure. In the description of the process according to the flowchart in Fig. 8, the components of the transmitter 11 are the subject of the operation. The subject of the process according to the flowchart in Fig. 8 may be the transmitter 11.

[0070] 8, first, acquiring unit 111 acquires a plurality of information sequences to be transmitted (step S111). Each of the plurality of information sequences includes information directed to each of multiple receivers 15-1 to 15-n.

[0071] Next, the encoder 112 uses an error correction code to encode each of the acquired information sequences into a code sequence having a sequence length for each of the receivers 15-1 to 15-n (step S112).

[0072] Next, amplifier 113 multiplies each of the multiple code sequences by a predetermined real amplitude value (step S113).

[0073] Next, the adder 115 adds together the multiple code sequences multiplied by the real amplitude values ​​(step S114). The added code sequence is a code sequence (communication signal) in which carrier signals (code sequences) for each of the multiple receivers 15 are multiplexed in the amplitude value direction.

[0074] Next, the transmitting unit 117 modulates the code sequence (communication signal) in which the code sequences for the multiple receivers 15 are multiplexed in the amplitude value direction, and transmits the modulated communication signal (step S115). In the communication path, the real amplitude value of the communication signal (code sequence) transmitted from the transmitting unit 117 changes. In addition, in the communication path, a noise sequence is added to the communication signal (code sequence) transmitted from the transmitting unit 117.

[0075] [Receiver] Fig. 9 is a flowchart showing an example of the operation of the receiver 15 in the present disclosure. In the description of the process according to the flowchart in Fig. 9, the components of the receiver 15 are the subject of the operation. The subject of the process according to the flowchart in Fig. 9 may be the receiver 15.

[0076] 9, first, the receiver 151 receives a communication signal (code sequence) (step S151). The received communication signal (code sequence) is a signal in which carrier signals (code sequences) directed to a plurality of transmitters 11 are superimposed.

[0077] Next, the decoder 152 decodes the information sequence from the code sequence to be decoded using the error correction code (step S152). In the first decoding, the carrier signal (code sequence) corresponds to the code sequence to be decoded. In the second and subsequent decoding, the decoder 152 decodes the information sequence from the updated code sequence to be decoded.

[0078] If the decoded information sequence is not the one to be received (No in step S153), the re-encoder 153 re-encodes the decoded information sequence (step S154). In the i-th re-encoding, the re-encoder 153 re-encodes the information sequence under the i-th encoding condition. Under the i-th encoding condition, the information sequence u i On the other hand, if the decoded information sequence is the one to be received (Yes in step S153), the process proceeds to step S157.

[0079] After step S154, the multiplier 155 multiplies the re-encoded code sequence by a predetermined real amplitude value to generate a replica signal (step S155). In the i-th multiplication, the multiplier 155 multiplies the re-encoded code sequence by the real amplitude value under the i-th multiplication condition. Under the i-th multiplication condition, the real amplitude value of the i-th carrier signal at the time of receiving the communication signal is used.

[0080] Next, the subtractor 156 subtracts the replica signal from the code sequence to be decoded to update the code sequence to be decoded (step S156). After step S156, the process returns to step S152. In the first subtraction, the subtractor 156 subtracts the replica signal from the received code sequence (the code sequence to be decoded) and updates the code sequence to be decoded with the code sequence after the subtraction. In the second or subsequent i-th subtraction, the subtractor 156 subtracts the i-th replica signal from the code sequence to be decoded updated in the previous subtraction and updates the code sequence to be decoded with the code sequence after the subtraction.

[0081] In step S153, if the decoded information sequence is to be received (Yes in step S153), the corrector 157 corrects the decoding error of the information sequence to be received (step S157). If the decoding error of the information sequence is not to be corrected in the receiver 15, step S157 is omitted.

[0082] Next, the output unit 159 outputs the information sequence in which the decoding error has been corrected (step S158). If the decoding error of the information sequence is not corrected in the receiver 15, the output unit 159 outputs the information sequence including the decoding error.

[0083] As described above, the communication system of the present embodiment includes a transmitter and a receiver. The communication system of the present embodiment includes a plurality of receivers. The transmitter includes an acquisition unit, an encoder, an amplifier, an adder, and a transmission unit. The acquisition unit acquires a plurality of information sequences, which are bit sequences. Next, the encoder uses an error correction code to encode each of the plurality of information sequences into a code sequence, which is a soft-value data sequence. The amplifier multiplies each of the plurality of code sequences by a predetermined real amplitude value. The adder adds the plurality of code sequences multiplied by the real amplitude value to each other to generate a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction. The transmission unit modulates the generated communication signal and transmits the modulated communication signal. The receiver includes a reception unit, a decoder, a re-encoder, a multiplier, a subtractor, and an output unit. The reception unit receives a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction. The decoder uses an error correction code to decode an information sequence, which is a bit sequence, from a code sequence to be decoded, which is a soft-value data sequence derived from the communication signal. If the decoded information sequence is not the one to be received, the re-encoder re-encodes the decoded information sequence. The multiplier multiplies the re-encoded code sequence by a predetermined real amplitude value to generate a replica signal. The subtractor subtracts the replica signal from the code sequence to be decoded to update the code sequence to be decoded. If the decoded information sequence is the one to be received, the output unit outputs the information sequence to be received.

[0084] The transmitter of this embodiment encodes each of the multiple information sequences with an error correction code. The transmitter of this embodiment adds multiple code sequences encoded with a correction code to generate a communication signal in which multiple carrier signals are multiplexed in the amplitude value direction. The receiver of this embodiment uses an error correction code to decode an information sequence, with a communication signal in which multiple carrier signals are multiplexed in the amplitude value direction as a code sequence to be decoded. When an information sequence that is not to be received is decoded, the receiver of this embodiment re-encodes the information sequence and multiplies it by a predetermined real amplitude value to generate a replica signal. The receiver of this embodiment subtracts the replica signal from the code sequence to be decoded to update the code sequence to be decoded. The receiver of this embodiment decodes the information sequence from the updated code sequence to be decoded using the error correction code. The receiver of this embodiment repeats these processes until the information sequence to be received is decoded. In this way, the receiver of this embodiment decodes the information sequence to be received from the communication signal in which multiple carrier signals are superimposed, using the error correction code. Therefore, according to the communication system of this embodiment, wireless communication using a communication signal in which carrier signals are multiplexed in the amplitude value direction can be realized.

[0085] In a transmitter according to an aspect of the present embodiment, the multiple information sequences include a first information sequence and a second information sequence. The encoder encodes the first information sequence into a first code sequence using a first error correcting code. The encoder encodes the second information sequence into a second code sequence using a second error correcting code. The amplifier amplifies the first code sequence with a first real amplitude value. The amplifier amplifies the second code sequence with a second real amplitude value. For example, the first real amplitude value is greater than the second real amplitude value. The adder adds a first carrier signal including the first code sequence amplified with the first real amplitude value and a second carrier signal including the second code sequence amplified with the second real amplitude value to generate a communication signal in which the second carrier signal is superimposed on the first carrier signal. According to this aspect, a communication signal in which the carrier signal is doubled in the amplitude value direction can be transmitted.

[0086] The receiver according to one aspect of the present embodiment includes a corrector that corrects a decoding error contained in a decoded information sequence. According to this aspect, an information sequence in which the decoding error has been corrected is obtained.

[0087] In one aspect of this embodiment, the decoder decodes a first information sequence from the carrier signal using a first error correcting code. If the first information sequence is to be received, the output unit outputs the decoded first information sequence. If the first information sequence is not to be received, the re-encoder re-encodes the decoded first information sequence into a first code sequence. The multiplier multiplies the re-encoded first code sequence by a first real amplitude value to generate a first replica signal. The subtractor subtracts the first replica signal from the code sequence to be decoded to update the code sequence to be decoded. The decoder decodes a second information sequence from the updated code sequence to be decoded using a second error correcting code. The output unit outputs the decoded second information sequence. According to this aspect, the information sequence to be received can be decoded from a communication signal in which the carrier signal is duplicated in the amplitude value direction.

[0088] In the receiver according to one aspect of the present embodiment, the re-encoder, the multiplier, the subtractor, and the decoder repeat the process until the information sequence to be received is obtained. According to this aspect, the information sequence to be received can be decoded from the communication signal in which the carrier signal is multiplexed in the amplitude value direction.

[0089] Second embodiment Next, a transmitter according to a second embodiment will be described with reference to the drawings. The transmitter according to this embodiment has a simplified configuration of the transmitter included in the communication system according to the first embodiment.

[0090] (composition) 10 is a block diagram showing an example of a configuration of the transmitter 21 in the present disclosure. The transmitter 21 includes an acquisition unit 211, an encoder 212, an amplifier 213, an adder 215, and a transmission unit 217.

[0091] The acquiring unit 211 acquires a plurality of information sequences, which are bit sequences. The encoder 212 uses an error correcting code to encode each of the plurality of information sequences into a code sequence, which is a soft-value data sequence. The amplifier 213 multiplies each of the plurality of code sequences by a predetermined real amplitude value. The adder 215 adds the plurality of code sequences multiplied by the real amplitude value to each other to generate a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction. The transmitter 217 modulates the generated communication signal and transmits the modulated communication signal.

[0092] (operation) Fig. 11 is a flowchart showing an example of the operation (transmission method) of the transmitter 21 in the present disclosure. In the description of the process according to the flowchart of Fig. 11, the components of the transmitter 21 are the subject of the operation. The subject of the operation of the process according to the flowchart of Fig. 11 may be the transmitter 21.

[0093] In FIG. 11, first, the acquiring unit 211 acquires a plurality of information sequences, which are bit sequences (step S211).

[0094] Next, the encoder 212 uses an error correcting code to encode each of the multiple information sequences into a code sequence that is a soft-value data sequence (step S212).

[0095] Next, the amplifier 213 multiplies each of the multiple code sequences by a predetermined real amplitude value (step S213).

[0096] Next, adder 215 adds together the multiple code sequences multiplied by the real amplitude values ​​to generate a communication signal in which multiple carrier signals are multiplexed in the amplitude value direction (step S214).

[0097] Next, the transmitting unit 217 modulates the generated communication signal and transmits the modulated communication signal (step S215).

[0098] The transmitter of this embodiment encodes each of the multiple information sequences with an error correcting code. The transmitter of this embodiment adds the multiple code sequences encoded with the error correcting codes to generate a communication signal in which multiple carrier signals are multiplexed in the amplitude value direction. Therefore, the transmitter of this embodiment can realize wireless communication using a communication signal in which carrier signals are multiplexed in the amplitude value direction.

[0099] Third embodiment Next, a receiver according to a third embodiment will be described with reference to the drawings. The receiver according to this embodiment has a simplified configuration of the receiver included in the communication system according to the first embodiment.

[0100] (composition) 12 is a block diagram showing an example of a configuration of the receiver 35 in the present disclosure. The receiver 35 includes a receiving unit 351, a decoder 352, a re-encoder 353, a multiplier 355, a subtractor 356, and an output unit 359.

[0101] The receiver 351 receives a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction. The decoder 352 uses an error correcting code to decode a code sequence to be decoded, which is a soft data sequence derived from the communication signal, into an information sequence, which is a bit sequence. If the decoded information sequence is not the one to be received, the decoder re-encodes the decoded information sequence. The multiplier 355 multiplies the re-encoded code sequence by a predetermined real amplitude value to generate a replica signal. The subtractor 356 subtracts the replica signal from the code sequence to be decoded to update the code sequence to be decoded. If the decoded information sequence is the one to be received, the decoder outputs the information sequence to be received.

[0102] (operation) Fig. 13 is a flowchart showing an example of the operation (reception method) of the receiver 35 in the present disclosure. In the description of the process according to the flowchart in Fig. 13, the components of the receiver 35 are the subject of the operation. The subject of the operation of the process according to the flowchart in Fig. 13 may be the receiver 35.

[0103] In FIG. 13, first, the receiving unit 351 receives a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction (step S351).

[0104] Next, the decoder 352 decodes, by using an error correcting code, the code sequence to be decoded, which is a soft-value data sequence derived from the communication signal, into an information sequence, which is a bit sequence (step S352).

[0105] If the decoded information sequence is not the one to be received (No in step S353), the decoded information sequence is re-encoded (step S354). On the other hand, if the decoded information sequence is the one to be received (Yes in step S353), the output unit 359 outputs the information sequence to be received (step S357).

[0106] After step S354, the multiplier 355 multiplies the re-encoded code sequence by a predetermined real amplitude value to generate a replica signal (step S355).

[0107] Next, the subtractor 356 subtracts the replica signal from the code sequence to be decoded to update the code sequence to be decoded (step S356). After step S356, the process returns to step S352.

[0108] The receiver of this embodiment uses an error correcting code to decode an information sequence, using a communication signal in which multiple carrier signals are multiplexed in the amplitude value direction. When an information sequence that is not to be received is decoded, the receiver of this embodiment re-encodes the information sequence and multiplies it by a predetermined real amplitude value to generate a replica signal. The receiver of this embodiment subtracts the replica signal from the code sequence to be decoded to update the code sequence to be decoded. The receiver of this embodiment uses an error correcting code to decode an information sequence from the updated code sequence to be decoded. The receiver of this embodiment repeats these processes until the information sequence to be received is decoded. In this way, the receiver of this embodiment uses an error correcting code to decode an information sequence to be received from a communication signal in which multiple carrier signals are superimposed. Therefore, the receiver of this embodiment can realize wireless communication using a communication signal in which carrier signals are multiplexed in the amplitude value direction.

[0109] (Hardware) Next, a hardware configuration for executing the processes in the present disclosure will be described with reference to the drawings. Here, an information processing device 90 (computer) in Fig. 14 is given as an example of such a hardware configuration. The information processing device 90 in Fig. 14 is an example of a configuration for executing the processes in the present disclosure, and does not limit the scope of the present disclosure.

[0110] As shown in Fig. 14, an information processing device 90 includes a processor 91, a main storage device 92, an auxiliary storage device 93, an input / output interface 95, and a communication interface 96. In Fig. 14, the interface is abbreviated as I / F (Interface). The processor 91, the main storage device 92, the auxiliary storage device 93, the input / output interface 95, and the communication interface 96 are connected to each other via a bus 98 so as to be able to communicate data with each other. In addition, the processor 91, the main storage device 92, the auxiliary storage device 93, and the input / output interface 95 are connected to a network such as the Internet or an intranet via the communication interface 96.

[0111] The processor 91 loads a program (instructions) stored in the auxiliary storage device 93 or the like into the main storage device 92. For example, the program is a software program for executing the processes in the present disclosure. The processor 91 executes the program loaded into the main storage device 92. The processor 91 executes the processes in the present disclosure by executing the program.

[0112] The main memory device 92 has an area in which a program is loaded. The processor 91 loads a program stored in the auxiliary memory device 93 or the like in the main memory device 92. The main memory device 92 is realized by a volatile memory such as a dynamic random access memory (DRAM). Furthermore, a non-volatile memory such as a magneto resistive random access memory (MRAM) may be configured / added to the main memory device 92.

[0113] The auxiliary storage device 93 stores various data such as programs. The auxiliary storage device 93 is realized by a local disk such as a hard disk or a flash memory. Note that it is also possible to configure the main storage device 92 to store various data and omit the auxiliary storage device 93.

[0114] The input / output interface 95 is an interface for connecting the information processing device 90 to peripheral devices based on standards and specifications. The communication interface 96 is an interface for connecting to an external system or device through a network such as the Internet or an intranet based on standards and specifications. The input / output interface 95 and the communication interface 96 may be a common interface for connecting to an external device.

[0115] Input devices such as a keyboard, a mouse, and a touch panel may be connected to the information processing device 90 as necessary. These input devices are used to input information and settings. When a touch panel is used as the input device, a screen having the function of the touch panel becomes the interface. The processor 91 and the input devices are connected via an input / output interface 95.

[0116] The information processing device 90 may be equipped with a display device for displaying information. When the display device is equipped, the information processing device 90 is equipped with a display control device (not shown) for controlling the display of the display device. The information processing device 90 and the display device are connected via an input / output interface 95.

[0117] The information processing device 90 may be provided with a drive device. The drive device mediates between the processor 91 and a recording medium (program recording medium) in reading data and programs stored in the recording medium and writing the processing results of the information processing device 90 to the recording medium. The information processing device 90 and the drive device are connected via an input / output interface 95.

[0118] The above is an example of a hardware configuration for enabling the processing in the present disclosure. The hardware configuration in FIG. 14 is an example of a hardware configuration for executing the processing in the present disclosure, and does not limit the scope of the present disclosure. A program for causing a computer to execute the processing in the present disclosure is also included in the scope of the present disclosure.

[0119] A program recording medium on which a program for executing the processing in this embodiment is recorded is also included in the scope of the present invention. For example, the program recording medium is a computer-readable non-transient recording medium. The recording medium can be realized by an optical recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc). The recording medium may be realized by a semiconductor recording medium such as a USB (Universal Serial Bus) memory or an SD (Secure Digital) card. The recording medium may also be realized by a magnetic recording medium such as a flexible disk or other recording medium.

[0120] The components in the present disclosure may be combined in any manner. The components in the present disclosure may be realized by software. The components in the present disclosure may be realized by a circuit.

[0121] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-mentioned embodiments. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, each embodiment can be appropriately combined with other embodiments.

[0122] A part or all of the above-described embodiments can be described as, but is not limited to, the following supplementary notes. (Appendix 1) an acquisition unit for acquiring a plurality of information sequences, each of which is a bit sequence; an encoder that encodes each of the plurality of information sequences into a code sequence that is a soft-value data sequence using an error correcting code; an amplifier for multiplying each of the plurality of code sequences by a predetermined real amplitude value; an adder that adds together the plurality of code sequences multiplied by the real amplitude values ​​to generate a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; a transmitter section for modulating the generated communication signal and transmitting the modulated communication signal. (Appendix 2) The plurality of information sequences include a first information sequence and a second information sequence; The encoder comprises: encoding the first information sequence into a first code sequence using a first error correcting code; encoding the second information sequence into a second code sequence using a second error correcting code; The amplifier comprises: amplifying the first code sequence by a first real amplitude value; amplifying the second code sequence with a second real amplitude value; The adder is 2. The transmitter of claim 1, which generates the communication signal in which the second carrier signal is superimposed on the first carrier signal by adding a first carrier signal including the first code sequence amplified by the first real amplitude value and a second carrier signal including the second code sequence amplified by the second real amplitude value. (Appendix 3) 3. The transmitter of claim 2, wherein the first real amplitude value is greater than the second real amplitude value. (Appendix 4) a receiving unit for receiving a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; a decoder for decoding, by using an error correcting code, a code sequence to be decoded, which is a soft-value data sequence derived from the communication signal, into an information sequence, which is a bit sequence; a re-encoder for re-encoding the decoded information sequence if the decoded information sequence is not a sequence to be received; a multiplier for multiplying the re-encoded code sequence by a predetermined real amplitude value to generate a replica signal; a subtractor that subtracts the replica signal from the code sequence to be decoded to update the code sequence to be decoded; and an output unit that outputs the information sequence to be received if the decoded information sequence is the information sequence to be received. (Appendix 5) 5. The receiver of claim 4, comprising a corrector for correcting decoding errors contained in the decoded information sequence. (Appendix 6) The decoder comprises: decoding a first information sequence from the carrier signal using a first error correcting code; The output unit is If the first information sequence is to be received, outputting the decoded first information sequence; The re-encoder If the first information sequence is not a reception target, re-encoding the decoded first information sequence into a first code sequence; The multiplier comprises: multiplying the re-encoded first code sequence by a first real amplitude value to generate a first replica signal; The subtractor comprises: updating the code sequence to be decoded by subtracting the first replica signal from the code sequence to be decoded; The decoder comprises: Decoding a second information sequence from the updated code sequence to be decoded by using a second error correcting code; The output unit is 5. The receiver of claim 4, which outputs the decoded second information sequence. (Appendix 7) 7. The receiver of claim 6, wherein the re-encoder, the multiplier, the subtractor, and the decoder repeat the process until the information sequence to be received is obtained. (Appendix 8) A transmitter according to any one of Supplementary Notes 1 to 3; A communication system comprising: a receiver according to any one of appendixes 4 to 7. (Appendix 9) Obtaining a plurality of information sequences which are bit sequences; encoding each of the plurality of information sequences into a code sequence that is a soft-value data sequence using an error correcting code; multiplying each of a plurality of said code sequences by a predetermined real amplitude value; adding the code sequences multiplied by the real amplitude values ​​to each other to generate a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; modulating the generated communication signal; A method of transmitting said modulated communication signal. (Appendix 10) The plurality of information sequences include a first information sequence and a second information sequence; In the encoding, encoding the first information sequence into a first code sequence using a first error correcting code; encoding the second information sequence into a second code sequence using a second error correcting code; In the amplification, amplifying the first code sequence by a first real amplitude value; amplifying the second code sequence with a second real amplitude value; In the addition, 10. The transmitter of claim 9, further comprising: a first carrier signal including the first code sequence amplified by the first real amplitude value and a second carrier signal including the second code sequence amplified by the second real amplitude value, and generating the communication signal in which the second carrier signal is superimposed on the first carrier signal. (Appendix 11) 11. The transmitter of claim 10, wherein the first real amplitude value is greater than the second real amplitude value. (Appendix 12) receiving a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; using an error correcting code to decode a code sequence which is a soft-value data sequence derived from the communication signal into an information sequence which is a bit sequence; re-encoding the decoded information sequence if the decoded information sequence was not intended for reception; Multiplying the recoded code sequence by a predetermined real amplitude value to generate a replica signal; updating the code sequence to be decoded by subtracting the replica signal from the code sequence to be decoded; If the decoded information sequence is the information sequence to be received, the information sequence to be received is output. (Appendix 13) 13. The receiver of claim 12, wherein the receiver corrects decoding errors contained in the decoded information sequence. (Appendix 14) In the decoding, decoding a first information sequence from the carrier signal using a first error correcting code; In the output, If the first information sequence is to be received, outputting the decoded first information sequence; In the re-encoding, If the first information sequence is not a reception target, re-encoding the decoded first information sequence into a first code sequence; In the multiplication, multiplying the re-encoded first code sequence by a first real amplitude value to generate a first replica signal; In the subtraction, updating the code sequence to be decoded by subtracting the first replica signal from the code sequence to be decoded; In the decoding, Decoding a second information sequence from the updated code sequence to be decoded by using a second error correcting code; In the output, 13. The receiver of claim 12, which outputs the decoded second information sequence. (Appendix 15) 15. The receiver of claim 14, wherein the re-encoding, multiplication, subtraction, and decoding are repeated until the information sequence to be received is obtained. [Explanation of symbols]

[0123] 1. Communication Systems 11, 21 Transmitter 15, 35 Receiver 111, 211 Acquisition Department 112, 212 encoder 113, 213 Amplifier 115, 215 adder 117, 217 Transmitter 151, 351 Receiver 152, 352 Decoder 153, 353 reencoder 155, 355 multiplier 156, 356 subtractor 157 Corrector 159, 359 Output section

Claims

1. an acquisition unit for acquiring a plurality of information sequences, each of which is a bit sequence; an encoder that encodes each of the plurality of information sequences into a code sequence that is a soft-value data sequence using an error correcting code; an amplifier for multiplying each of the plurality of code sequences by a predetermined real amplitude value; an adder that adds together the plurality of code sequences multiplied by the real amplitude values ​​to generate a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; a transmitter section for modulating the generated communication signal and transmitting the modulated communication signal.

2. The plurality of information sequences include a first information sequence and a second information sequence; The encoder comprises: encoding the first information sequence into a first code sequence using a first error correcting code; encoding the second information sequence into a second code sequence using a second error correcting code; The amplifier comprises: amplifying the first code sequence with a first real amplitude value; amplifying the second code sequence with a second real amplitude value; The adder is 2. The transmitter according to claim 1, further comprising: a first carrier signal including the first code sequence amplified by the first real amplitude value and a second carrier signal including the second code sequence amplified by the second real amplitude value, the first carrier signal being superimposed on the second carrier signal to generate the communication signal.

3. 3. The transmitter of claim 2, wherein said first real amplitude value is greater than said second real amplitude value.

4. a receiving unit for receiving a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; a decoder for decoding, by using an error correcting code, a code sequence to be decoded, which is a soft-value data sequence derived from the communication signal, into an information sequence, which is a bit sequence; a re-encoder for re-encoding the decoded information sequence if the decoded information sequence is not a sequence to be received; a multiplier for multiplying the re-encoded code sequence by a predetermined real amplitude value to generate a replica signal; a subtractor that subtracts the replica signal from the code sequence to be decoded to update the code sequence to be decoded; and an output unit that outputs the information sequence to be received if the decoded information sequence is the information sequence to be received.

5. 5. The receiver according to claim 4, further comprising a corrector for correcting a decoding error contained in the decoded information sequence.

6. The decoder comprises: decoding a first information sequence from the carrier signal using a first error correcting code; The output unit is If the first information sequence is to be received, outputting the decoded first information sequence; The re-encoder If the first information sequence is not a reception target, re-encoding the decoded first information sequence into a first code sequence; The multiplier comprises: multiplying the re-encoded first code sequence by a first real amplitude value to generate a first replica signal; The subtractor comprises: updating the code sequence to be decoded by subtracting the first replica signal from the code sequence to be decoded; The decoder comprises: Decoding a second information sequence from the updated code sequence to be decoded using a second error correcting code; The output unit is 5. The receiver according to claim 4, which outputs the decoded second information sequence.

7. 7. The receiver of claim 6, wherein the re-encoder, the multiplier, the subtractor, and the decoder repeat the process until the information sequence to be received is obtained.

8. A transmitter according to any one of claims 1 to 3; A communication system comprising a receiver according to any one of claims 4 to 7.

9. Obtaining a plurality of information sequences which are bit sequences; encoding each of the plurality of information sequences into a code sequence that is a soft-value data sequence using an error correcting code; multiplying each of a plurality of said code sequences by a predetermined real amplitude value; adding the code sequences multiplied by the real amplitude values ​​to each other to generate a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; modulating the generated communication signal; A method of transmitting said modulated communication signal.

10. receiving a communication signal in which a plurality of carrier signals are multiplexed in the amplitude value direction; using an error correcting code to decode a code sequence which is a soft-value data sequence derived from the communication signal into an information sequence which is a bit sequence; re-encoding the decoded information sequence if the decoded information sequence was not intended for reception; Multiplying the recoded code sequence by a predetermined real amplitude value to generate a replica signal; updating the code sequence to be decoded by subtracting the replica signal from the code sequence to be decoded; If the decoded information sequence is the information sequence to be received, the information sequence to be received is output.

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