CN102075487B - Multidimensional constellation mapping based coding and modulating method, demodulating and decoding method and system - Google Patents

Abstract

The invention relates to a multidimensional constellation mapping based coding and modulating method, demodulating and decoding method and system. The coding and modulating method comprises the following steps of: carrying out channel coding and bit interleaving on input information bits to obtain coded interleaved bits; carrying out K-dimensional pulse amplitude modulated constellation mapping on the coded and interleaved bits to obtain a constellation mapping symbol of a K-dimensional real-number vector, wherein K is a positive integer; carrying out constellation rotation on the constellation mapping symbol to obtain a multidimensional rotated constellation mapping symbol of the K-dimensional real-number vector; and carrying out dimension conversion and general real-number interleaving on the multidimensional rotated constellation mapping symbol to obtain a coded and modulated symbol, and outputting the coded and modulated symbol. The method and system in the invention can ensure that the performances of a coding and modulating system and a corresponding demodulating and decoding system approach the channel capacity at medium and low frequency spectrum efficiency under the AWGN (Added White Gaussian Noise) and fading channel conditions and meanwhile, the throughput of the system is taken into consideration.

Description

Code modulating method, demodulating and decoding method and system based on the multi-dimensional constellation mapping

Technical field

The present invention relates to the digital information transmission field, relate in particular to a kind of code modulating method, demodulating and decoding method and system based on the multi-dimensional constellation mapping.

Background technology

The basic task of digital communication system, particularly wireless communication system is to utilize finite bandwidth that the high speed of digital information, efficient errorless transmission are provided.In order to adapt to the transmission demand of digital information under common analog channel, channel coding technology need to be combined with digital modulation technique usually.Coding modulation technique is effective ways and the important means that realizes the wireless communication system basic task.The combination of chnnel coding and modulation consists of code modulation system, and it is the subsystem of digital communication system transmitting terminal, also is one of its nucleus module, and corresponding coding modulation technique also is the core technology of digital communication system.Corresponding with code modulation system, as to separate the mediation channel-decoding demodulating and decoding system in conjunction with the formation receiver, corresponding demodulating and decoding technology also is the core technology of digital communication system.

In general, chnnel coding is for memoryless channel design and optimization, in order to adapt to the channel-decoding of receiving terminal, improve the diversity order (Diversity Order) of code modulation system, modal means are to adopt interleaving technology so that the imformosome of input demodulator and decoder reveals approximate memoryless characteristic.

So-called modulation, expression is carried out conversion process to input data or signal, to obtain being suitable for the signal of transmission, comprises various analog-modulated and digital modulation technique.To typical digital communication system, digital modulation technique mainly comprises constellation mapping technology and subsequent treatment technology, such as multi-carrier modulation technology and molding filtration technology.So-called constellation mapping will be carried " symbol " sequence that finite field " bit " sequence mapping of digital information becomes to be suitable for transmitting exactly.The value space of each symbol can be one dimension real number space, two-dimentional real number space (being complex number space or complex number plane) or the real number space of higher-dimension (for example space corresponding to multiple-antenna MIMO system signal transmission) more.Constellation mapping comprises two key elements, i.e. planisphere and constellation point mapping mode.Planisphere represents the set of all values compositions of constellation mapping output symbol, and wherein, each of planisphere put a kind of value of corresponding output symbol.Constellation point mapping mode represents input bit (group) to the mapped specific relation of constellation point, and perhaps constellation point is to the mapped specific relation of bit (group), and each constellation point is corresponding one by one with the bit group that a bit or a plurality of bit form usually.The planisphere of at present the most common and practical complex number space mainly contains QAM (QuadratureAmplitude Modulation, quadrature amplitude modulation), PSK (Phase Shift Keying, phase shift keying) and APSK (Amplitude-Phase Shift Keying, Amplitude phase shift keying) modulation technique; The planisphere of real number space is mainly PAM (Pulse AmplitudeModulation, pulse amplitude modulation).In the decoding demodulating system of receiving terminal, what constellation was shone upon is the mapping of constellation solution, is called for short and separates mapping.Usually, the constellation solution is shone upon according to planisphere and constellation point mapping mode, obtains the bit soft information of one or more bits of corresponding receiving symbol in conjunction with channel condition information.

A basic index weighing coding modulation technique is: under the condition of given spectrum efficiency and error control target, and the gap of required signal-to-noise ratio threshold distance information public opinion-medium.Spectrum efficiency represents with the effective information bit that every one dimension of planisphere M dimension real number space can transmit usually, for example, and for the traditional 64QAM system that does not add chnnel coding, its spectrum efficiency is 3 bit/symbol/dimension, wherein, every constellation symbol is comprised of the bidimensional real number, portability 6 bit informations.The error control target is usually with bit error rate or code word error rate (claiming again Block Error Rate) expression.The information public opinion-medium represents to reach the required lowest signal-to-noise of errorless transmission usually.According to information theory ABC, for given code modulation system and given channel condition, information public opinion-medium (supposing to represent with signal to noise ratio) is the monotonically increasing function of spectrum efficiency, determines by spectrum efficiency is unique.

The basic theory of coding modulation technique is Shannon information theory, it mainly is point-to-point alone family information theory, its core concept is: from the angle of mutual information maximization, at additive white Gaussian noise (Additive White Gaussian Noise, AWGN) under the channel, when transmit power limited, only have when white Gaussian Profile is satisfied in the output of code modulation system, just can reach channel capacity.Channel coding theorem is pointed out in the simultaneously information theory, as long as the rate of delivering a letter less than channel capacity, then certainly exists the code modulation system of errorless transmission.Yet basic theory only solves code modulated Existence problems, and how constructing a practicable code modulation system that approaches the limit is the target that recent decades, the communications field laid siege to always.

To the equal restricted abominable transmission channel of typical power and bandwidth, transmission channel such as wideband wireless mobile communication and received terrestrial digital broadcasting system, coding modulation technique is the important guarantee of transmission reliability and system spectral efficiency, therefore, the coding modulation technique as the industrial quarters standard of up-to-date wideband wireless mobile communication and received terrestrial digital broadcasting system employing has represented the highest level of the coding modulation technique of current practical application.Europe second generation ground digital television broadcast standard (DVB-T2) has adopted low-density checksum (Low Density Parity Check, LDPC) coding techniques, Bit Interleave technology and high-order QAM modulation technology (comprising constellation rotation technology and IQ interleaving technology); Europe second generation digital video broadcast-satellite standard (DVB-S2) has adopted Bit Interleave technology, LDPC coding techniques and high-order APSK modulation technique; Turbo coding techniques, Bit Interleave technology and high-order QAM modulation technology have been adopted in the LTE V8.1 motion of 3GPP tissue.

In academia, development through decades, coding modulation technique has been obtained tremendous development, the most typically as number G.Ungerboeck proposition Trellis-coded modulation (Trellis CodedModulation, TCM), referring to document G.Ungerboeck. " Channel coding withmultilevel phase signals. " IEEE Trans.Inform.Theory, no.28, pp55-67,1982.), and Bit Interleave coded modulation (the Bit-InterleavedCoded Modulation of E.Zehavi proposition, BICM), referring to document E.Zehavi, " 8PSK trellis codes fora Rayleigh channel, " IEEE Trans.Commun., vol.40, no.5, pp.873-884, May 1992.TCM is by the maximization Euclidean distance, so that its performance performance under awgn channel is excellent, but unsatisfactory under fading channel; BICM is then just opposite, and it is lost than TCM under awgn channel, but under fading channel original performance is arranged.The BICM system of receiving terminal iterative demapping and decoding, be (the BICM withIterative Demapping and Decoding of BICM-ID system, be called for short BICM-ID) independently proposed by people such as the people such as Xiaodong Li and Ten Brink, referring to document X.Li and J.A.Ritcey, " Bit-interleaved coded modulation with iterative decoding using softfeedback; " Electronics Letters, vol.34, no.10, pp.942-943, May 1998. and S.T.Brink, J.Speidel, and R.-H.Yan, " Iterative demapping and decodingfor multilevel modulation, " in Globecom ' 98,1998, the pp.579-584.BICM-ID system feeds back as the prior information of separating mapping by the information of the output of will decoding, and has increased Euclidean distance, thereby has obtained the error performance same good with TCM under awgn channel.But, traditional B ICM-ID has a higher error floor, even this is because the bit information of all feedbacks all is errorless, the error rate of system still by the characteristic of outer code (for linear code, depend primarily on minimum non-zero code weight and number thereof in the code book) conciliate the Harmonic Euclidean distance decision when shining upon, and the number that the minimum distance of traditional code word is less and it is corresponding is very many.

Yet, as a rule the BICM-ID system need to adopt the high-order constellation mapping with better by the iterative demapping transmission of information, so the spectrum efficiency that provides higher is convenient to usually in the BICM-ID system.For so that the BICM-ID system satisfies the demand of low frequency spectrum efficient, a kind of method is to adopt the outer code of low code check (such as the code word that adopts 1/4 code check) in the BICM-ID system, and another kind of method adopts multi-dimensional constellation figure exactly.Simultaneously, the robustness of traditional BICM-ID system is inadequate, namely can not be applicable to multiple transmission condition, and the BICM-ID system outstanding such as performance under awgn channel performs poor under fading channel.Signal space diversity (Signal Space Diversity, SSD) technology is proposed (referring to J.Boutros and E.Biterbo by J.Boutros at first, " Signal space diversity:a power-andbandwidth-efficient diversity technique for the Rayleigh fading channel; " IEEE Trans.Inform.Theory, vol.44, no.4, pp.1453-1467, July 1998.), can be effectively to anti-fading in conjunction with the rotation of suitable planisphere, but wherein optimum spin matrix is a disclosed difficult problem always.The basic operation of SSD technology is: will interweave through each dimension coordinate of signal after the constellation rotation, give rear module after then being reassembled into the signal of required dimension.Interweave (Coordinate Interleaving) by coordinate, SSD can the Effective Raise diversity order in conjunction with the planisphere rotation so that each dimension that originally belongs in the same symbol under the fading channel has experienced independent decline.

Summary of the invention

The purpose of this invention is to provide a kind of code modulating method, demodulating and decoding method and system based on the multi-dimensional constellation mapping, the method and system can be under AWGN and fading channel conditions, so that the performance of demodulating and decoding system code modulation system and corresponding is all approached channel capacity under the medium and low frequency spectrum efficiency, take into account simultaneously the handling capacity of system, can overcome the deficiencies in the prior art.

For achieving the above object, the present invention adopts following technical scheme.

A kind of coded modulation and demodulating and decoding method based on the multi-dimensional constellation mapping provided by the invention, wherein code modulating method comprises step:

S1. input information bits is carried out chnnel coding and Bit Interleave, obtain the code interleaving bit;

The K dimension pulse amplitude modulation constellation mapping of S2. described code interleaving bit having been rotated, or carry out K dimension pulse amplitude modulation constellation mapping and constellation rotation, obtain multidimensional and rotated the constellation mapping symbol, wherein, K is positive integer;

S3. described multidimensional has been rotated that the constellation mapping symbol carries out dimension conversion and general real number interweaves, obtained coded modulation symbol and output;

Wherein demodulating and decoding method comprises step:

S4. utilize the phase information of the channel condition information of outside input, carry out to received signal phasing;

S5. the signal behind the described phasing is carried out dimension conversion and general real solution interweaves, obtain de-interleaved signal, the amplitude information of the channel condition information that the outside is inputted also carries out general real solution and interweaves;

If S6. separate for the first time mapping, then directly described de-interleaved signal is carried out the solution mapping that multidimensional has been rotated constellation, obtain separating the rear soft information of mapping, otherwise, utilize the external information of last channel-decoding output as prior information, carry out the solution mapping that multidimensional has been rotated constellation, obtain separating the rear soft information of mapping;

S7. soft information after the described solution mapping is carried out deinterleaving and channel-decoding;

Set iterations or channel-decoding verification succeeds if S8. reach, delivery channel decoded result then, otherwise the result interweaves again to channel-decoding, obtains the external information of channel-decoding output, and returns step S6.

Wherein, step S2 further comprises:

S2.1 carries out constellation rotation to K dimension pulse amplitude modulation constellation point, the K dimension pulse amplitude modulation constellation point of having been rotated;

The K dimension pulse amplitude modulation constellation mapping that S2.2 has rotated to described code interleaving bit, the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol;

Or comprise:

S2.1 carries out K dimension pulse amplitude modulation constellation mapping to described code interleaving bit, obtains the constellation mapping symbol of K dimension real number vector;

S2.2 carries out constellation rotation to described constellation mapping symbol, and the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol.

Wherein, among the step S2: when K=1, described constellation mapping is the pulse amplitude modulation constellation mapping; When K=2, described constellation mapping is the quadrature amplitude modulation constellation mapping; When K=3, described constellation mapping is three-dimensional pulse amplitude modulation constellation mapping; When K=4, described constellation mapping is four-dimensional pulse amplitude modulation constellation mapping.

Wherein, among the step S2.2, the method for described constellation rotation is for using non-singular matrix that described K dimension real number vector is carried out matrixing.

Wherein, described non-singular matrix is orthogonal matrix.

During K=2, described orthogonal matrix is $R=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right],$ Wherein, $a=1/\sqrt{1+{\mathrm{\λ}}^2},$ $b=\mathrm{\λ}/\sqrt{1+{\mathrm{\λ}}^2},$ λ is real number;

During K=3, described orthogonal matrix is $R=\left[\begin{array}{ccc}a& b& c\\ b& c& a\\ -c& -a& -b\end{array}\right],$ Wherein, a=(1+ λ)/(1+ λ+λ ²), b=(λ+λ ²)/(1+ λ+λ ²), c=-λ/(1+ λ+λ ²), λ is real number;

During K=4, described orthogonal matrix is $R=\left[\begin{array}{cc}{M}_1& -M_2\\ M_2& {\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_1\end{array}\right],$ Wherein, ${\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_1=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right],$ ${\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_2=\left[\begin{array}{cc}c& d\\ -d& c\end{array}\right],$ And $a=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $b=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $c=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $d=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ λ, γ are real number.

Wherein, step S3 further comprises:

S31. described multidimensional is rotated the constellation mapping symbol and carried out the dimension conversion, obtained the first one dimension real number symbol;

S32. described the first one dimension real number symbol is carried out general real number and interweave, obtain the second one dimension real number symbol;

S33. described the second one dimension real number symbol is carried out the dimension conversion, obtain the coded modulation symbol, and output.

Wherein, among the step S3, described dimension conversion is with the K of input _InDimension real number vector is converted to K _OutDimension real number vector, its method is, with N _InIndividual K _InAll common N on the every one dimension of dimension real number vector _InK _InIndividual real number symbol is reformulated N _OutIndividual K _OutDimension real number vector, wherein, N _InK _In=N _OutK _Out, K _InAnd K _OutBe positive integer.

The present invention also provides a kind of coded modulation and demodulating and decoding system based on the multi-dimensional constellation mapping, and wherein code modulation system comprises:

The code interleaving module is used for input information bits is carried out chnnel coding and Bit Interleave, obtains the code interleaving bit;

The constellation mapping module, the K that is used for described code interleaving bit has been rotated ties up the pulse amplitude modulation constellation mapping, or carries out K dimension pulse amplitude modulation constellation mapping and constellation rotation, obtains multidimensional and has rotated the constellation mapping symbol, and wherein, K is positive integer;

Dimension conversion and interleaving block, the constellation mapping symbol carries out the dimension conversion and general real number interweaves for described multidimensional has been rotated, obtains coded modulation symbol and output;

Wherein the demodulating and decoding system comprises:

Phase correction module for the phase information of the channel condition information that utilizes outside input, is carried out phasing to received signal;

Dimension inverse conversion and de-interleaving block are used for the signal behind the described phasing is carried out the dimension conversion and general real solution interweaves, and obtain de-interleaved signal, and the amplitude information of the channel condition information that the outside is inputted also carries out general real solution and interweaves;

Separate mapping block, if separate for the first time mapping, then directly described de-interleaved signal is carried out multidimensional and rotated the mapping of constellation solution, obtain separating the rear soft information of mapping, otherwise, utilize the external information of last channel-decoding output as prior information, carry out the solution mapping that multidimensional has been rotated constellation, obtain separating the rear soft information of mapping;

The deinterleaving decoder module is used for soft information after the described solution mapping is carried out deinterleaving and channel-decoding, obtains the channel-decoding result;

Control module is set iterations or channel-decoding verification succeeds if reach, delivery channel decoded result then, otherwise, the external information of channel-decoding output is interweaved again, as prior information, feed back to the solution mapping block.

Method and system of the present invention have greatly improved the diversity order under the fading channel by the constellation rotation technology of using multidimensional pulse amplitude modulation planisphere and the general real number interleaving technology of changing in conjunction with dimension; In conjunction with the receiving terminal demodulating and decoding method, so that channel capacity is approached by the BICM-ID system when the medium and low frequency spectrum efficiency, under the multiple channel condition.

Description of drawings

Fig. 1 is the code modulating method flow chart based on the multi-dimensional constellation mapping according to one embodiment of the present invention;

Fig. 2 is the demodulating and decoding method flow chart based on the multi-dimensional constellation mapping according to one embodiment of the present invention;

Fig. 3 is according to the code modulated planisphere of the 3D-2PAM of one embodiment of the present invention;

Fig. 4 be according to the 3D-2PAM code modulation system of one embodiment of the present invention under the independent Rayleigh fading channel with different λ values under mutual information;

Fig. 5 is the mutual information of code modulation system under independent Rayleigh fading channel based on optimal transform matrix according to one embodiment of the present invention;

Fig. 6 is the BICM-ID transmitting terminal code modulation system block diagram of the employing multi-dimensional constellation figure of embodiment 1;

Fig. 7 is the BICM-ID receiving terminal demodulating and decoding system block diagram of the employing multi-dimensional constellation figure of embodiment 1;

Fig. 8 (a)-Fig. 8 (b) is the coded modulation block diagram that adopts the BICM-ID system transmitting terminal of cascaded channel coding among the embodiment 2;

Fig. 9 is the error performance based on the code modulation system of optimal transform matrix according to one embodiment of the present invention;

Adopt the coded modulation block diagram of the BICM-ID system transmitting terminal of cascaded channel coding among Figure 10 (a)-Figure 10 (b) embodiment 3.

Embodiment

Code modulating method, demodulating and decoding method and system based on the multi-dimensional constellation mapping that the present invention proposes are described as follows in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, the code modulating method based on the multi-dimensional constellation mapping according to one embodiment of the present invention comprises step:

S1. input information bits is carried out chnnel coding and Bit Interleave, obtain the code interleaving bit;

Wherein, channel coding method comprises the combination of checksum coding, CRC coding, BCH block encoding, RS block encoding, convolution code, punctured convolutional code, Turbo coding, LDPC coding, serially concatenated chnnel coding, parallel cascade chnnel coding or above various coded systems.

The K dimension pulse amplitude modulation constellation mapping of S2. the code interleaving bit having been rotated, or carry out K dimension pulse amplitude modulation constellation mapping and constellation rotation, obtain multidimensional and rotated the constellation mapping symbol, wherein, K is positive integer;

Wherein, step S2 further comprises:

S2.1 carries out constellation rotation to K dimension pulse amplitude modulation constellation point, the K dimension pulse amplitude modulation constellation point of having been rotated;

The K dimension pulse amplitude modulation constellation mapping that S2.2 has rotated to the code interleaving bit, the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol;

Or comprise:

S2.1 carries out K dimension pulse amplitude modulation constellation mapping to the code interleaving bit, obtains the constellation mapping symbol of K dimension real number vector;

S2.2 carries out constellation rotation to the constellation mapping symbol, and the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol.

Multidimensional pulse amplitude modulation constellation mapping (being designated as KD-PAM, wherein the K representation dimension) is a kind of constellation mapping that bit or bit group rule is mapped to multidimensional real number space point, and its every one dimension is traditional pulse amplitude modulation constellation mapping (being PAM).When dimension K=1, KD-PAM is conventional P AM; When K=2, KD-PAM is traditional Q AM; When K=3, remember that the 3D-PAM planisphere that every one dimension contains n constellation point is 3D-nPAM; Below the size (being number of constellation points) of constellation set of graphs represents with alphabetical M in the narration, usually M=n ^KA kind of simple and effective multi-dimensional constellation figure building mode is: directly expand the one dimension planisphere to K dimension (K〉1), can obtain K dimension pulse amplitude modulation planisphere (referred to as KD-PAM), wherein can obtain K dimension pulse amplitude modulation planisphere (2D-PAM), i.e. qam constellation figure during K=2.In conjunction with the SSD technology, the multi-dimensional constellation figure that the one dimension constellation extension obtains carries out planisphere rotation (equivalence is called for short constellation rotation for the constellation point rotation) usually, can improve the performance of BICM-ID system under fading channel.

Be used for the bit number m that the bit group of constellation mapping comprises and determined by number of constellation points M, for equiprobability constellation mapping, m=log ₂(M).Special case to M=2 obtains m=1, and namely the bit group only comprises a bit.Each constellation point of K dimension real number space is the K dimension real number vector (being K dimension real number symbol) that K real number forms, with x=[x ₁x ₂X _K] expression, wherein x _i(1≤i≤K) is real number.

S3. the constellation mapping symbol that step S2 is obtained carries out constellation rotation, and the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol;

The method of constellation rotation obtains new K dimension real number vector β, namely for using transformation matrix (being the constellation rotation matrix) R that K dimension real number vector α is carried out matrixing

β=αR，?

α=[α wherein ₁α ₂α _k] be the K dimension real number vector before the constellation rotation, β=[β ₁β ₂β _k] be the K dimension real number vector after the constellation rotation.Through every one dimension of vector after the constellation rotation, i.e. β _i, obtain through the linearity combination by the K dimension component of vectorial α before the constellation rotation, so constellation rotation can improve the diversity order of whole system effectively.Transformation matrix R is non-singular matrix, and consistent for the average energy that guarantees symbol before and after the constellation rotation and space structure characteristic, capable or K is listed as the K of transformation matrix R for the preferred orthogonal matrix of transformation matrix R, K orthogonal vectors for example can selecting one group of orthogonal basis in the K dimension real number space.Not carrying out constellation rotation is a special case of constellation rotation, and at this moment, transformation matrix is unit matrix.

When K=2, orthogonal matrix is preferably $R=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right]$

Wherein, $a=1/\sqrt{1+{\mathrm{\&lambda;}}^2},$ $b=\mathrm{\&lambda;}/\sqrt{1+{\mathrm{\&lambda;}}^2},$ λ is real number;

When K=3, orthogonal matrix is preferably $R=\left[\begin{array}{ccc}a& b& c\\ b& c& a\\ -c& -a& -b\end{array}\right]$

Wherein, a=(1+ λ)/(1+ λ+λ ²), b=(λ+λ ²)/(1+ λ+λ ²), c=-λ/(1+ λ+λ ²), λ is real number;

When K=4, orthogonal matrix is preferably $R=\left[\begin{array}{cc}{M}_1& -M_2\\ M_2& {\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_1\end{array}\right]$

Wherein, ${\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_1=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right],$ ${\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_2=\left[\begin{array}{cc}c& d\\ -d& c\end{array}\right],$ And $a=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $b=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $c=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $d=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ λ, γ are real number.

S3. the multidimensional that step S2 is obtained has rotated that the constellation mapping symbol carries out dimension conversion and general real number interweaves, and obtains coded modulation symbol and output.

The dimension conversion is with the K of input _InDimension real number vector is converted to K _OutDimension real number vector, its method is, with N _InIndividual K _InAll common N on the every one dimension of dimension real number vector _InK _InIndividual real number symbol is reformulated N _OutIndividual K _OutDimension real number vector, wherein, N _InK _In=N _OutK _Out, K _InAnd K _OutBe positive integer.

Definition spectrum efficiency r is the information bit of each dimension transmission of average each symbol, and unit is " the every dimension of the every symbol of bit (bits/sym/dim) ".Be the chnnel coding of rate and K that M is ordered dimension equiprobability constellation mapping to code check, spectrum efficiency is

r=rate*m/K?(bits/sym/dim)

Complex signal of actual usually each transmission, it is two-dimentional real number signal, therefore each dimension spectrum efficiency is that r means that the entrained information bit of each transmission is 2r, i.e. 2r bits/channel use, and corresponding code modulation system spectrum efficiency is 2r bits/s/Hz usually.For different spectrum efficiency demands, usually select M=2 ^mIndividual constellation point, wherein m is positive integer.

Wherein, step S1 can further comprise:

S11. input information bits is carried out the first component code coding or the first component code group coding, obtain the first coded-bit;

S12. input information bits is carried out Bit Interleave, carry out again second component code or second component code character coding, obtain the second coded-bit;

S13. merge the first coded-bit and the second coded-bit, obtain the code interleaving bit.

Step S1 also can further comprise:

S11 '. input information bits is carried out the first component code or the first component code group coding, obtain the first coded-bit;

S12 '. the first coded-bit is carried out Bit Interleave, obtain interleaving bits;

S13 '. interleaving bits is carried out second component code or second component code character coding, obtain the code interleaving bit.

In addition, step S3 further comprises:

S31. multidimensional is rotated the constellation mapping symbol and carried out the dimension conversion, obtained the first one dimension real number symbol;

S32. the first one dimension real number symbol is carried out general real number and interweave, obtain the second one dimension real number symbol;

S32. the second one dimension real number symbol is carried out the dimension conversion, obtain coded modulation symbol and output.

As shown in Figure 2, demodulating and decoding method corresponding to code modulating method based on the multi-dimensional constellation mapping according to one embodiment of the present invention comprises step:

S4. utilize the phase information of the channel condition information of outside input, carry out to received signal phasing;

S5. the signal behind the described phasing is carried out dimension conversion and general real solution interweaves, obtain de-interleaved signal, also carry out general real solution behind the amplitude information of the channel condition information of outside input and interweave, so that follow-up constellation solution is shone upon;

If S6. for the first time solution mapping is then directly carried out multidimensional to de-interleaved signal and rotated the mapping of constellation solution, obtain separating the rear soft information of mapping, otherwise, utilize the external information of last channel-decoding output as prior information, carry out the solution mapping that multidimensional has been rotated constellation, obtain separating the rear soft information of mapping;

S7. soft information after separating mapping is carried out deinterleaving and channel-decoding;

Set iterations or channel-decoding verification succeeds if S8. reach, delivery channel decoded result then, otherwise the result interweaves again to channel-decoding, obtains the external information of channel-decoding output, and returns step S6.

The present invention also provides the code modulation system based on the multi-dimensional constellation mapping of the above-mentioned code modulating method of a kind of correspondence, and this system comprises: the code interleaving module, be used for input information bits is carried out chnnel coding and Bit Interleave, and obtain the code interleaving bit; The constellation mapping module, the K that is used for described code interleaving bit has been rotated ties up the pulse amplitude modulation constellation mapping, or carries out K dimension pulse amplitude modulation constellation mapping and constellation rotation, obtains multidimensional and has rotated the constellation mapping symbol, and wherein, K is positive integer; Dimension conversion and interleaving block, the constellation mapping symbol carries out the dimension conversion and general real number interweaves for described multidimensional has been rotated, obtains coded modulation symbol and output.

Wherein, the constellation mapping module also can further comprise: the constellation rotation unit is used for K dimension pulse amplitude modulation constellation point is carried out constellation rotation the K dimension pulse amplitude modulation constellation point of having been rotated; The constellation mapping unit, the K that is used for coded-bit has been rotated ties up the pulse amplitude modulation constellation mapping, and the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol;

Or comprise: the constellation mapping unit, be used for coded-bit is carried out K dimension pulse amplitude modulation constellation mapping, obtain the constellation mapping symbol of K dimension real number vector; The constellation rotation unit is used for the constellation mapping symbol is carried out constellation rotation, and the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol.

Dimension conversion and interleaving block can further comprise: the first dimension converting unit, be used for the constellation rotation symbol is carried out the dimension conversion, and obtain the first one dimension real number symbol; General real number interleave unit is used for that the first one dimension real number symbol is carried out general real number and interweaves, and obtains the second one dimension real number symbol, and obviously, its input and output are one dimension real number symbol; The second dimension converting unit is used for described the second one dimension real number symbol is carried out the dimension conversion, obtains the coded modulation symbol, and output.Wherein, the dimension conversion is with the K of input _InDimension real number symbol transition is the K of output _OutDimension real number symbol, K _InAnd K _OutBe positive integer, value is determined by external control signal.

The present invention corresponding to a kind of and above-mentioned demodulating and decoding method also provides at the demodulating and decoding system based on the multi-dimensional constellation mapping, this system comprises: phase correction module, be used for utilizing the phase information of the outside channel condition information of inputting, carry out to received signal phasing; Dimension inverse conversion and de-interleaving block are used for the signal behind the phasing is carried out the dimension conversion and general real solution interweaves, and obtain de-interleaved signal, and the amplitude information of the channel condition information that the outside is inputted also carries out general real solution and interweaves; Separate mapping block, if separate for the first time mapping, then directly described de-interleaved signal is carried out multidimensional and rotated the mapping of constellation solution, obtain separating the rear soft information of mapping, otherwise, utilize the external information of last channel-decoding output as prior information, carry out multidimensional and rotated the mapping of constellation solution, obtain separating the rear soft information of mapping; The deinterleaving decoder module is used for soft information after separating mapping is carried out deinterleaving and channel-decoding, obtains the channel-decoding result; Control module, if reach set iterations or the channel-decoding result correct, delivery channel decoded result then, otherwise, the external information of channel-decoding output is interweaved again, as prior information, feed back to the solution mapping block.

In addition, in the present invention, adopt the maximum mutual information criterion to choose optimal transform matrix: to suppose that signal is through the flatness decline, after interweaving through dimension conversion and general real number, the input signal constellation signal of separating mapping block in the receiving terminal demodulating and decoding system can be modeled as Y=HX+N, and wherein X represents that multidimensional rotated the signal output of constellation mapping, H represents the channel gain of each dimension of this constellation symbol, N represents the multidimensional noise, and expression is multiplied each other by element, and Y is the multidimensional signal of receiving.Rotating under the multi-dimensional constellation figure restrictive condition, and the known CSI(Channel State of receiving terminal Information channel condition information) situation under, mutual information may be calculated:

$I(X;Y|H)={\mathrm{<figure-callout\; id="2"\; label="log"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">log</figure-callout>}}_2\left|\mathrm{\&chi;}\right|-E_{x,y,h}\left[{\log }_2\frac{{\mathrm{\&Sigma;}}_{\tilde{x}\&Element;\mathrm{\&chi;}}p\left(y\right|\tilde{x},h)}{p\left(y\right|x,h)}\right]---\left(1\right)$

Wherein, the constellation point set that χ represents to have rotated, | χ | the size of expression constellation point set, for example the 3D-2PAM planisphere contains 8 points, and as shown in Figure 3,3D-2PAM constellation point set sizes is 8 so.To identical constellation mapping, different constellation rotation matrixes obtain different χ, thereby affect the mutual information shown in the following formula.The present invention selects the criterion of optimal transform matrix to be so that above-mentioned mutual information reaches maximum.

For two-dimentional planisphere, the orthogonal transform matrix among the present invention has following form:

$R=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right]$

Wherein, $a=1/\sqrt{1+{\mathrm{\&lambda;}}^2},$ $b=\mathrm{\&lambda;}/\sqrt{1+{\mathrm{\&lambda;}}^2},$ λ is real number.For 2D-PAM signal, code check (code check≤3/4) commonly used and independent Rayleigh channel, λ=± 1 is optimal solution.

For three-dimensional planisphere, the orthogonal transform matrix among the present invention can be expressed as:

$R=\left[\begin{array}{ccc}a& b& c\\ b& c& a\\ -c& -a& -b\end{array}\right]$

Wherein, a=(1+ λ)/(1+ λ+λ ²), b=(λ+λ ²)/(1+ λ+λ ²), c=-λ/(1+ λ+λ ²), λ is real number.The transformation matrix R that different λ is corresponding different, for different channel conditions or different encoder bit rates, optimal transform matrix is (with R ^*Expression) difference.Consider in the present invention for independent Rayleigh fading channel, only consider code check (code check≤3/4) commonly used, especially pay close attention to 1/2 code check.For 3D-2PAM, because it contains 8 various constellations points, therefore each constellation symbol can be carried 3bit information in coded system not, and when adopting 1/2 code check, portable useful information bit is the every symbols of 1.5 bits, is equivalent to the every dimension of 0.5 bit.Therefore, setting signal to noise ratio (Signal to Noise Ratio, SNR) is 1.5dB, so under 3D-2PAM and the independent Rayleigh fading channel, so that mutual information is approximately the every symbol of 1.5 bits shown in (1) formula.In the situation that planisphere, fading channel and signal to noise ratio are given, the mutual information shown in (1) formula is the function of λ, can be written as I (λ).According to the symmetry of 3D-2PAM planisphere, and respectively tie up the symmetry that decline presents, be not difficult to obtain I (1/ λ)=I (λ), and I (1-λ)=I (λ).I (λ) value under the different λ value conditions is not difficult to find out from figure as shown in Figure 3, is locally optimal solution in the λ span shown in the figure of λ=1 or λ=-0.5.And according to above-mentioned character, can judge that λ=1 ,-0.5 or-2 is globally optimal solution.Above-mentioned optimal solution is preferred solution for other three-dimensional orthogonal planispheres such as 3D-4PAM, 3D-8PAM etc.Same method also can be applied to other scene, such as other planispheres, other channels and other code checks.

For four-dimensional planisphere, the orthogonal transform matrix among the present invention has following form:

$R=\left[\begin{array}{cc}{M}_1& -M_2\\ M_2& {\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_1\end{array}\right]$

Wherein, ${\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_1=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right],$ ${\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_2=\left[\begin{array}{cc}c& d\\ -d& c\end{array}\right],$ And $a=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $b=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $c=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $d=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ λ, γ are real number.

Obviously, for given channel condition, given signal to noise ratio and the given four-dimensional planisphere of not rotation, the mutual information shown in (1) formula can be written as the function I (γ, λ) of γ and λ.For the 4D-nPAM planisphere, can obtain equally following character: I (γ, λ)=I (λ, γ), I (1/ γ, λ)=I (γ, λ)=I (γ, λ) and I (γ, 1/ λ)=I (γ ,-λ)=I (γ, λ).Only need to be set in delta-shaped region 0≤γ≤1,0≤λ≤γ to the span of γ and λ when so, seeking optimal transform matrix gets final product.For 4D-2PAM, under independent Rayleigh channel and the 1/2 code check condition, when λ=γ=1, be optimal solution.Thereby the R matrix that obtains is an elementary row rank transformation of normalization Hadamard matrix.So the present invention proposes, for 4D-2PAM, independent Rayleigh channel and code check commonly used (≤3/4), 4 * 4 Hadamard matrix and elementary row rank transformation thereof all can be thought optimal transform matrix.This optimal transform matrix is all effective such as 4D-4PAM, 4D-8PAM etc. for other four-dimensional quadrature planispheres.

In order to reflect that better optimal constellation is rotated in the lower gain that can bring of Rayleigh fading channel, the present invention proposes and has chosen optimum transformation matrix, and to have provided 2D-2PAM(be QPSK)/the mutual information value shown in lower (1) formula of 3D-2PAM/4D-2PAM restriction is along with the variation tendency of signal to noise ratio, as shown in Figure 4.Enumerate channel capacity that understand to reconcile Rayleigh channel under the known CSI condition of code system among the figure, and 2D-2PAM(is QPSK in not rotation of the planisphere situation)/mutual information value under the 3D-2PAM/4D-2PAM planisphere restrictive condition is as a reference; Three middle curves are under above-mentioned three kinds of planisphere restrictive conditions, choose the resulting mutual information value of suitable transformation matrix.As can be seen from the figure, select optimum transformation matrix to bring obvious gain under fading channel, and dimension is higher, mutual information more approaches the channel capacity of fading channel.

Embodiment 1-adopts the BICM-ID system of multi-dimensional constellation figure

The present embodiment has proposed the BICM-ID system of a kind of employing multi-dimensional constellation figure according to one embodiment of the present invention.For so that the BICM-ID system under the medium and low frequency spectrum efficiency, the performance of approaching shannon limit can be provided under AWGN and fading channel simultaneously, the present embodiment proposes to adopt the multi-dimensional constellation figure of constellation rotation in the BICM-ID code modulation system, simultaneously in conjunction with the SSD technology.

Be illustrated in figure 6 as code modulation system and the method schematic diagram of this BICM-ID system transmitting terminal:

S101. input information bits is carried out chnnel coding and Bit Interleave, obtain the code interleaving bit;

S102. the code interleaving bit is carried out the constellation mapping of K dimension pulse amplitude modulation, obtain the constellation mapping symbol of K dimension real number vector, wherein, K is positive integer;

S103. the constellation mapping symbol is carried out constellation rotation, the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol;

S104. multidimensional having been rotated the constellation mapping symbol carries out dimension and is converted to the first one dimension real number symbol;

S105. the first one dimension real number symbol is carried out general real number and interweave, obtain the second one dimension real number symbol;

S106. the second one dimension real number symbol is carried out the dimension conversion, obtain coded modulation symbol and output.

Wherein, the chnnel coding among the step S101 can be convolution code, block code, LDPC code, Turbo code, serially concatenated chnnel coding or parallel cascade chnnel coding;

Figure 6 shows that and adopt multi-dimensional constellation figure to carry out constellation mapping and in conjunction with the code modulation system block diagram of the BICM-ID transmitting terminal of SSD technology.Information to be transmitted is carried out after chnnel coding and the Bit Interleave through the code interleaving module first, carry out the multi-dimensional constellation mapping in the constellation mapping module, then carry out constellation rotation in the constellation rotation module, carry out subsequently dimension conversion 1 so that the multidimensional real number signal is converted to the one dimension real number signal, carrying out afterwards general real number interweaves, signal after interweaving will carry out obtaining the signal (normally two-dimentional real number signal) of required dimension after the dimension conversion 2, and give the transmitting terminal subsequent module.

This code modulation system is characterised in that:

1. the chnnel coding among the step S101 includes but not limited to Turbo code, serial concatenation of codes, parallel cascade codes, LDPC code, convolution code etc.;

2. the Bit Interleave among the step S101 can be cancelled under special circumstances, and such as chnnel coding code length long enough, perhaps chnnel coding is the inner concatenated coding that Bit Interleave is arranged;

3. the constellation rotation among multi-dimensional constellation mapping and the step S103 can unite two into one among the step S102, only need to finish for the multi-dimensional constellation mapping of rotating constellation (be called for short multidimensional and rotated constellation mapping, receiving terminal has correspondingly rotated the mapping of constellation solution referred to as multidimensional) and get final product.

Be illustrated in figure 7 as and adopt the higher-dimension planisphere and in conjunction with the demodulating and decoding system block diagram of the BICM-ID system receiving terminal of SSD technology.At receiving terminal, usually the signal that receives is converted to the one dimension real number signal through the dimension converting unit 2 ' (changing 2 corresponding with the transmitting terminal dimension) that phase correction module is given the dimension modular converter after carrying out phasing at step S202 first at step S201, carry out that general real solution interweaves and finish dimension conversion 1 ' (changing 1 corresponding with the transmitting terminal dimension) at step S204 afterwards that to recover multidimensional signal, the amplitude information of CSI is too through giving the solution mapping block after deinterleaving and the dimension conversion simultaneously at step S203.Auxiliary lower at the amplitude information of CSI, carry out the mapping of constellation solution at step S205-step S207 according to having rotated the multidimensional signal of constellation after to deinterleaving, operation afterwards is consistent with traditional B ICM-ID receiving terminal.

This receiving terminal demodulating and decoding system is characterised in that:

1. receive signal at the auxiliary lower completing steps S201 phasing of the phase information of CSI.

2. only the amplitude information of CSI is carried out that the general real solution of step S203 interweaves and step S204 dimension conversion 1 ', give afterwards and separate mapping block and rotated the mapping of constellation solution with the auxiliary multidimensional of finishing.

3. step S205 constellation solution mapping and step S206 channel-decoding are by step S206 deinterleaving and the step S208 loop of formation that interweaves again, and iteration is carried out.

Embodiment 2

In order further to show employing multi-dimensional constellation figure that the present invention proposes and in conjunction with the performance advantage of the BICM-ID system of optimal transform matrix, the present embodiment provides a BICM-ID system with every design parameter that adopts 3D-nPAM, and provides the error performance of this system.

The code modulating method of this system comprises step:

S301. input bit is carried out chnnel coding and Bit Interleave, obtain the code interleaving bit;

This system adopts the cascaded channel coding techniques, comprises two kinds of technology of parallel cascade and serially concatenated.Such as Fig. 8 (a) with 8(b), parallel cascade and the BICM of serially concatenated chnnel coding and the coded modulation block diagram of BICM-ID system transmitting terminal are adopted in expression respectively.Wherein, the representative instance of parallel cascade chnnel coding is with the parallel cascade Turbo code of convolution code as component code, and the representative instance of serially concatenated chnnel coding is with the serially concatenated Turbo code of convolution code as component code.The coded modulation block diagram has adopted two interleave unit, comprise the interleave unit of cascaded channel coding inside and the Bit Interleave unit between cascaded channel coding and the constellation mapping, increased the complexity of coded modulation and demodulating and decoding, second interleave unit can have been removed under certain conditions.The concrete steps of chnnel coding and Bit Interleave are as follows:

S301.a carries out the first component code coding to information bit, obtains the first coded-bit;

S301.b carries out carrying out second component code coding behind the Bit Interleave to information bit, obtains the second coded-bit;

S301.c obtains coded-bit with the first coded-bit and the merging of the second coded-bit;

Perhaps, the concrete steps of this chnnel coding and Bit Interleave are as follows:

S301.d carries out the first component code coding to information bit, obtains the first coded-bit;

S301.e carries out Bit Interleave to the first coded-bit, obtains interleaving bits;

S301.f carries out second component code coding to interleaving bits, obtains the second coded-bit, and the second coded-bit is exactly the code interleaving bit;

S302. coded-bit is carried out the constellation mapping of three-dimensional pulse amplitude modulation, obtain the constellation mapping symbol of three-dimensional real number vector;

Multidimensional pulse amplitude modulation constellation mapping is a kind of constellation mapping that bit or bit group rule is mapped to multidimensional real number space point.When dimension K=3, K dimension real number space degenerates into three dimensions, is 3D-nPAM, and wherein n represents the number of constellation points of every one-dimensional space, obviously number of constellation points M=n ³

For different spectrum efficiency demands, usually select M=2 ^mIndividual constellation point, wherein m is positive integer.

S303. the constellation mapping symbol that step S302 is obtained carries out constellation rotation, obtains the constellation rotation symbol of three-dimensional real number vector;

Wherein, the three-dimensional real number vector (being three-dimensional real number symbol) that constellation rotation will be inputted carries out matrixing, the three-dimensional real number vector (being three-dimensional real number symbol) that obtains exporting, and wherein transformation matrix is preferably orthogonal matrix; Further, transformation matrix can be chosen as unit matrix (namely not rotating), can also select the optimal transform matrix of describing among the embodiment 2:

$R=\left[\begin{array}{ccc}a& b& c\\ b& c& a\\ -c& -a& -b\end{array}\right]$

A=(1+ λ)/(1+ λ+λ wherein ²), b=(λ+λ ²)/(1+ λ+λ ²), c=-λ/(1+ λ+λ ²), λ is real number, and preferred λ=1 ,-0.5 or-2;

S304. the constellation rotation symbol that step S303 is obtained carries out the dimension conversion and general real number interweaves, and obtains coded modulation symbol and output.

For the three-dimensional real number vector with constellation rotation output carries out interface, be provided with the first dimension switch process; For the two-dimentional real number vector that need to export with code modulation system carries out interface, be provided with the second dimension switch process.The three-dimensional real number vector that the dimension conversion will be inputted is converted to two-dimentional real number vector, and it is operating as, with N ₁All real number symbols on the every one dimension of individual three-dimensional real number vector (are total to 3N ₁Individual) reformulation N ₂Individual two-dimentional real number vector, wherein, 3N ₁=2N ₂, N ₁, N ₂Be positive integer.

In order to show the performance of system proposed by the invention, provide a specific coding modulating system that adopts the 3D-2PAM planisphere in the present embodiment, provide its every detail parameters: comprise outer code, Doping code word, constellation mapping mode, code length etc.In given iterations situation, provided in detail its error performance, as shown in Figure 9.The design parameter of this system is as follows:

● outer code: code check is 1/2 [7,5] ₈Nonsystematic convolutional code;

● Bit Interleave: pseudo random interleaving;

● the Doping code word: code check is 12 status system convolution codes, and Doping leads and is made as 100, and namely per the 100th information bit replaced by check bit;

● code length: 192,000 bits;

● iterations: 100;

● constellation rotation parameter: λ=1;

● mapping mode: the order not 3D-2PAM constellation set of rotation is { x ₀=(1 ,-1 ,-1), x ₁=(1 ,-1 ,+1), x ₂=(1 ,+1 ,-1) ..., x ₇=(+1 ,+1 ,+1) }, mapping mode is 0 → x ₇, 1 → x ₁, 2 → x ₀, 3 → x ₆, 4 → x ₄, 5 → x ₂, 6 → x ₃And 7 → x ₅

Embodiment 3

In order further to show employing multi-dimensional constellation figure that the present invention proposes and in conjunction with the performance advantage of the BICM-ID system of optimum spin matrix, the present embodiment provides a BICM-ID system with every design parameter that adopts 4D-nPAM.

The code modulating method of this system's transmitting terminal comprises step:

S401. input bit is carried out chnnel coding and Bit Interleave, obtain the code interleaving bit;

Such as Figure 10 (a) and 10(b), represent respectively two kinds of BICM-ID system transmitting terminal coded modulation block diagrams that the present embodiment proposes, the component code character that employing has Concurrent Feature replaces traditional single component code, wherein, the system block diagram of parallel cascade chnnel coding is adopted in Figure 10 (a) expression, and the system block diagram of serially concatenated chnnel coding is adopted in Figure 10 (b) expression.The concrete steps of described chnnel coding and Bit Interleave are as follows:

S401.a carries out the coding of the first component code or the first component code character to information bit, obtain the first coded-bit;

S401.b carries out Bit Interleave to the first coded-bit, obtains interleaving bits;

S401.c carries out the coding of second component code or second component code character to interleaving bits, obtain the second coded-bit, and the second coded-bit is exactly the code interleaving bit;

Perhaps, the concrete steps of described chnnel coding and Bit Interleave are as follows:

S401.d carries out the first component code or the first component code group coding to information bit, obtains the first coded-bit;

S401.e carries out carrying out second component code or second component code character coding behind the Bit Interleave to information bit, obtains the second coded-bit;

S401.f obtains the code interleaving bit with the first coded-bit and the merging of the second coded-bit;

Wherein, component code can be convolution code or block code; The component code character forms by a plurality of component codes are parallel, and each component code of component code character can be convolution code or block code.

S402. the code interleaving bit is carried out the constellation mapping of four-dimensional pulse amplitude modulation, obtain the constellation mapping symbol of four-dimensional real number vector;

S403. described constellation mapping symbol is carried out constellation rotation, obtain the constellation rotation symbol of four-dimensional real number vector;

Wherein, the four-dimensional real number vector (being four-dimensional real number symbol) that constellation rotation will be inputted carries out matrixing, the four-dimensional real number vector (being four-dimensional real number symbol) that obtains exporting, and wherein transformation matrix is preferably orthogonal matrix; Further, transformation matrix can be chosen as unit matrix (namely not rotating), can also select the optimal transform matrix of describing among the embodiment 2:

$R=\left[\begin{array}{cc}{M}_1& -M_2\\ M_2& {\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_1\end{array}\right]$

Wherein ${\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_1=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right],$ ${\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="H2009102377694E00031.png"\; state="\{\{state\}\}">M</figure-callout>}}_2=\left[\begin{array}{cc}c& d\\ -d& c\end{array}\right],$ And $a=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $b=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $c=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $d=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ γ and λ are real number, and preferred γ=λ=1.

S404. described constellation rotation symbol is carried out dimension conversion and general real number interweaves, obtain the coded modulation symbol and export.

For the four-dimensional real number vector with constellation rotation output carries out interface, be provided with the first dimension switch process; For the two-dimentional real number vector that need to export with code modulation system carries out interface, be provided with the second dimension switch process.The four-dimensional real number vector that the dimension conversion will be inputted is converted to two-dimentional real number vector, and it is operating as, with N ₁All real number symbols on the every one dimension of individual four-dimensional real number vector (are total to 4N ₁Individual) reformulation N ₂Individual 2 dimension real number vectors, wherein, 4N ₁=2N ₂, N ₁, N ₂Be positive integer.

Above execution mode only is used for explanation the present invention; and be not limitation of the present invention; the those of ordinary skill in relevant technologies field; in the situation that do not break away from the spirit and scope of the present invention; can also make a variety of changes and modification; therefore all technical schemes that are equal to also belong to category of the present invention, and scope of patent protection of the present invention should be defined by the claims.

Claims (9)

1. coded modulation and demodulating and decoding method based on a multi-dimensional constellation mapping, wherein code modulating method comprises step:

S1. input information bits is carried out chnnel coding and Bit Interleave, obtain the code interleaving bit;

The K dimension pulse amplitude modulation constellation mapping of S2. described code interleaving bit having been rotated, or carry out K dimension pulse amplitude modulation constellation mapping and constellation rotation, obtain multidimensional and rotated the constellation mapping symbol, wherein, K is positive integer;

S3. described multidimensional has been rotated that the constellation mapping symbol carries out dimension conversion and general real number interweaves, obtained coded modulation symbol and output;

Wherein demodulating and decoding method comprises step:

S4. utilize the phase information of the channel condition information of outside input, carry out to received signal phasing;

S5. the signal behind the described phasing is carried out dimension conversion and general real solution interweaves, obtain de-interleaved signal, the amplitude information of the channel condition information that the outside is inputted also carries out general real solution and interweaves;

If S6. separate for the first time mapping, then directly described de-interleaved signal is carried out the solution mapping that multidimensional has been rotated constellation, obtain separating the rear soft information of mapping, otherwise, utilize the external information of last channel-decoding output as prior information, carry out the solution mapping that multidimensional has been rotated constellation, obtain separating the rear soft information of mapping;

S7. soft information after the described solution mapping is carried out deinterleaving and channel-decoding;

Set iterations or channel-decoding verification succeeds if S8. reach, delivery channel decoded result then, otherwise the result interweaves again to channel-decoding, obtains the external information of channel-decoding output, and returns step S6.

2. coded modulation and demodulating and decoding method based on the multi-dimensional constellation mapping as claimed in claim 1 is characterized in that, step S2 further comprises:

S2.1 carries out constellation rotation to K dimension pulse amplitude modulation constellation point, the K dimension pulse amplitude modulation constellation point of having been rotated;

The K dimension pulse amplitude modulation constellation mapping that S2.2 has rotated to described code interleaving bit, the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol;

Or comprise:

S2.1 carries out K dimension pulse amplitude modulation constellation mapping to described code interleaving bit, obtains the constellation mapping symbol of K dimension real number vector;

S2.2 carries out constellation rotation to described constellation mapping symbol, and the multidimensional that obtains K dimension real number vector has been rotated the constellation mapping symbol.

3. coded modulation and demodulating and decoding method based on the multi-dimensional constellation mapping as claimed in claim 2 is characterized in that, among the step S2:

When K=1, described constellation mapping is the pulse amplitude modulation constellation mapping;

When K=2, described constellation mapping is the quadrature amplitude modulation constellation mapping;

When K=3, described constellation mapping is three-dimensional pulse amplitude modulation constellation mapping;

When K=4, described constellation mapping is four-dimensional pulse amplitude modulation constellation mapping.

4. coded modulation and demodulating and decoding method based on the multi-dimensional constellation mapping as claimed in claim 2 is characterized in that, among the step S2.2, the method for described constellation rotation is for using non-singular matrix that described K dimension real number vector is carried out matrixing.

5. coded modulation and demodulating and decoding method based on the multi-dimensional constellation mapping as claimed in claim 4 is characterized in that, described non-singular matrix is orthogonal matrix.

6. such as claim 3-5 each described coded modulation and demodulating and decoding method based on the multi-dimensional constellation mapping, it is characterized in that,

During K=2, described orthogonal matrix is $R=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right],$ Wherein, $a=1/\sqrt{1+{\mathrm{\&lambda;}}^2},$ $b=\mathrm{\&lambda;}/\sqrt{1+{\mathrm{\&lambda;}}^2},$ λ is real number;

During K=3, described orthogonal matrix is $R=\left[\begin{array}{ccc}a& b& c\\ b& c& a\\ -c& -a& -b\end{array}\right],$ Wherein, a=(1+ λ)/(1+ λ+λ ²), b=(λ+λ ²)/(1+ λ+λ ²), c=-λ/(1+ λ+λ ²), λ is real number;

During K=4, described orthogonal matrix is $R=\left[\begin{array}{cc}{M}_1& -M_2\\ M_2& M_1\end{array}\right],$ Wherein, $M_1=\left[\begin{array}{cc}a& b\\ -b& a\end{array}\right],$ $M_2=\left[\begin{array}{cc}c& d\\ -d& c\end{array}\right],$ And $a=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $b=\frac{1}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $c=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{1}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ $d=\frac{\mathrm{\&gamma;}}{\sqrt{1+{\mathrm{\&gamma;}}^2}}\&CenterDot;\frac{\mathrm{\&lambda;}}{\sqrt{1+{\mathrm{\&lambda;}}^2}},$ λ, γ are real number.

7. coded modulation and demodulating and decoding method based on the multi-dimensional constellation mapping as claimed in claim 1 is characterized in that, step S3 further comprises:

S31. described multidimensional is rotated the constellation mapping symbol and carried out the dimension conversion, obtained the first one dimension real number symbol;

S32. described the first one dimension real number symbol is carried out general real number and interweave, obtain the second one dimension real number symbol;

S33. described the second one dimension real number symbol is carried out the dimension conversion, obtain the coded modulation symbol, and output.

8. such as claim 2 or 7 described coded modulation and demodulating and decoding methods based on the multi-dimensional constellation mapping, it is characterized in that, among the step S3, described dimension conversion is with the K of input _InDimension real number vector is converted to K _OutDimension real number vector, its method is, with N _InIndividual K _InAll common N on the every one dimension of dimension real number vector _InK _InIndividual real number symbol is reformulated N _OutIndividual K _OutDimension real number vector, wherein, N _InK _In=N _OutK _Out, K _InAnd K _OutBe positive integer.

9. coded modulation and demodulating and decoding system based on a multi-dimensional constellation mapping, wherein code modulation system comprises:

The code interleaving module is used for input information bits is carried out chnnel coding and Bit Interleave, obtains the code interleaving bit;

The constellation mapping module, the K that is used for described code interleaving bit has been rotated ties up the pulse amplitude modulation constellation mapping, or carries out K dimension pulse amplitude modulation constellation mapping and constellation rotation, obtains multidimensional and has rotated the constellation mapping symbol, and wherein, K is positive integer;

Dimension conversion and interleaving block, the constellation mapping symbol carries out the dimension conversion and general real number interweaves for described multidimensional has been rotated, obtains coded modulation symbol and output;

Wherein the demodulating and decoding system comprises:

Phase correction module for the phase information of the channel condition information that utilizes outside input, is carried out phasing to received signal;

Dimension inverse conversion and de-interleaving block are used for the signal behind the described phasing is carried out the dimension conversion and general real solution interweaves, and obtain de-interleaved signal, and the amplitude information of the channel condition information that the outside is inputted also carries out general real solution and interweaves;

Separate mapping block, if separate for the first time mapping, then directly described de-interleaved signal is carried out multidimensional and rotated the mapping of constellation solution, obtain separating the rear soft information of mapping, otherwise, utilize the external information of last channel-decoding output as prior information, carry out the solution mapping that multidimensional has been rotated constellation, obtain separating the rear soft information of mapping;

The deinterleaving decoder module is used for soft information after the described solution mapping is carried out deinterleaving and channel-decoding, obtains the channel-decoding result;

Control module is set iterations or channel-decoding verification succeeds if reach, delivery channel decoded result then, otherwise, the external information of channel-decoding output is interweaved again, as prior information, feed back to the solution mapping block.

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