CN101515918B - Multi-carrier modulator-demodulator - Google Patents

Abstract

The present invention discloses a multi-carrier modulator-demodulator, wherein the modulator comprises the following components: a multi-carrier data mapping device, a transmission pulse causality discretization device, a sub-carrier modulating device and a wideband data output device. The demodulator comprises the following components: a received wideband data discretization device, a received pulse discretization causality device, a sub-carrier modulating device and a sub-carrier data de-mapping device. The invention simultaneously discloses a quick algorithm for realizing multi-carrier modulation-demodulation. The multi-carrier modulator-demodulator and quick algorithm according to the invention can effectively realize the modulation-demodulation of multi-carrier with a realization complexity approximate to the orthogonal frequency division multiplexing (OFDM) system. The plan of the invention is not only suitable for the multi-carrier system with smaller sub-carrier bandwidth, but also suitable for the multi-carrier system with bigger sub-carrier bandwidth. The modulated multi-carrier bandwidth data have excellent out-of-band spectrum rolling-off characteristic. The system has a lower peak average power ratio (PAPR) when the wide sub-carrier is used for modulating.

Description

Multi-carrier modulation demodulation method and device

Technical field

The present invention relates to a kind of modulation-demodulation technique of multicarrier system, be meant modulation-demodulation technique and Rapid Realization device thereof in the multi-carrier communications systems especially.

Background technology

The multicarrier parallel transmission technology; Especially the orthogonal multiple carrier modulation technique that is the basis with OFDM (OFDM) technology; Obtained develop rapidly over nearly 20 years, from early stage asymmetrical digital subscriber loop technique (ADSL) technology, the digital television broadcasting in Europe finally (DVB) standard; And, all adopted the OFDM technology one after another to the 802.16d/e standard of nearly 2 years International Power Institution of Electronics (IEEE) and the Long Term Evolution (LTE) of third generation partnership projects (3GPP).

The OFDM modulation technique has its a series of advantage as a kind of typical parallel transmission technology; Less usually like subcarrier bandwidth, symbol time is long; Therefore have strong anti-multipath performance, realize modulation, demodulation, can realize the Rapid Realization of hardware easily with fast Fourier transform (FFT) and inverse fast fourier transform (IFFT) conversion; Can do the equilibrium of single tap at frequency domain, solve too complicated problems of traditional broadband CDMA system (CDMA) time domain equalization (RAKE receiver).With all technological the same; Some intrinsic shortcomings and deficiencies that ofdm system also has it, often bigger like the sub-carrier number of wideband OFDM system, as 512/1024/2048 etc.; Subcarrier bandwidth is less; As about 10kHz, this moment, the frequency domain of OFDM was the equal of the system of a threshold sampling, and this multicarrier system that just causes being basis with the OFDM technology is the system of a frequency deviation sensitivity normally.The bigger speed of a motor vehicle, the frequency shift (FS) that Frequency Synchronization deviation etc. is brought tends to make the systematic function of traditional ofdm system sharply to descend, when serious even can not work.Secondly; The more ofdm system of sub-carrier number often causes peak-to-average force ratio (PAPR) very high, the power efficiency of radio frequency (RF) is descended, if use slicing; The selectivity mapping; Methods such as coding solve, and the effect of these methods itself is limited on the one hand, tends to bring extra processing complexity on the other hand or introduces new noise effect.On the other hand; The OFDM technology is because its time domain waveform is the equal of a rectangular window; Therefore correspond to the sinc function at frequency domain response, the sinc function has the frequency domain slow characteristics of roll-offing, and this causes ofdm system not satisfy countries in the world, each department frequency templates (mask) requirement usually at frequency domain.And various windowings or other way can be introduced new processing complexity usually, and or can introduce new interference, or can reduce frequency spectrum imitates rule.Especially, less when the sub-carrier number of OFDM, in the time of the subcarrier broad, the outer scattered power of the band that this wide subcarrier brings is just bigger, and the way that is commonly used to solve the ofdm system out-of-band power of narrower subcarrier this moment often is difficult to prove effective.

Moreover along with the continuous maturation of mobile communication technology, market is increasingly high to the cost requirement at terminal.If directly the OFDM technology directly is used for the up link of multi-carrier communications systems, then traditional ofdm system will inevitably have influence on the power efficiency at terminal owing to the problem of high PAPR, will inevitably directly influence the cost and the performance at terminal.Current LTE has selected for use " discrete fourier transition-expansion OFDM " (DFT-S-OFDM) technological as up technology to this problem; Though change the problem of the high PAPR low power efficiency in terminal of having determined preferably; But the loss with the BER of system is a cost, and the outer too slow problem that descends of band still exists.

Summary of the invention

Main purpose of the present invention is to be to provide a kind of can effectively solve problems such as the outer leakage of band energy is too big in traditional OFDM multicarrier modulation system, PAPR is too high; The present invention not only is suitable for the narrower multicarrier system of the more subcarrier bandwidth of sub-carrier number; And being applicable to the multicarrier system of the less subcarrier bandwidth broad of sub-carrier number, this system can be applicable to the communication of uplink and downlink simultaneously.

Another object of the present invention is to provide the device of the above multi-carrier modulation of the enough fast algorithm implementation of a kind of ability, demodulating process; Make modulation system of the present invention not only outside band with on the PAPR, be superior to traditional ofdm system, implementation complexity is also similar with traditional OFDM.

A purpose more of the present invention is to provide a kind of method that realizes the subcarrier-modulated demodulation, makes the present invention can come to realize effectively the modulation of multicarrier with the implementation complexity near OFDM (OFDM) system.

According to first aspect present invention, the multi-carrier modulation method that is provided may further comprise the steps:

Data map to be sent to a plurality of subcarriers, is formed the parallel duplex subcarrier data;

The processing of discretization cause and effect is carried out in pulse to be sent, obtained discretization cause and effect transmission pulse signal;

Utilize discretization cause and effect transmission pulse that said parallel duplex subcarrier data is carried out the modulation of multidiameter delay subcarrier data, be generated as one tunnel modulated broadband serial data stream thus;

Export described modulated broadband serial data stream.

Wherein, when system design, give the subcarrier of system configuration broad, promptly the bandwidth of said subcarrier is greater than 10kHz;

When uplink, distribute less sub-carrier number to mobile subscriber terminal, can reduce the peak-to-average power ratio of portable terminal effectively, the number of subcarriers that promptly is used for uplink is less than the number of subcarriers that is used for downlink transfer.

According to second aspect present invention, the multi-carrier modulation device that is provided comprises:

The subcarrier data mapping device is used for data map to be sent to a plurality of subcarriers, forms the parallel duplex subcarrier data;

Send the makeup of pulse discretization cause and effect and put, be used for the processing of discretization cause and effect is carried out in pulse to be sent, obtain discretization cause and effect transmission pulse signal;

The subcarrier-modulated device is used for utilizing discretization cause and effect transmission pulse that said parallel duplex subcarrier data is carried out the modulation of multidiameter delay subcarrier data, is generated as one tunnel modulated broadband serial data stream thus;

Output modulated wideband data device is used for exporting described modulated broadband serial data stream.

According to a third aspect of the invention we, the multicarrier rectification device that is provided comprises:

Receive discretization wideband data device, be used for obtaining receiving serial bandwidth carrier data sampling and the discretization processing by the integral multiple of sample rate through the broadband serial data stream behind the channel;

The makeup of received pulse discretization cause and effect is put, and is used for received pulse is carried out the processing of discretization cause and effect, obtains discretization cause and effect received pulse signal;

Subcarrier de system device is used for utilizing discretization cause and effect received pulse signal that said reception serial bandwidth carrier data are carried out data demodulates, obtains the parallel duplex subcarrier data;

Subcarrier data is separated mapping device, is used for said parallel duplex subcarrier data is separated mapping treatment, obtains the corresponding data of each user.

The method of the multi-carrier modulation that is provided according to a forth aspect of the invention, may further comprise the steps:

A1) to symbolic variable and the variable that adds up certainly carry out initialization operation;

B1) from the multidiameter delay subcarrier data that the subcarrier mapping device generates, read as data to be modulated;

C1) to the IFFT Fast transforms of the multidiameter delay subcarrier data that reads;

D1) to many doubling times continuation of the data after the quick change of IFFT, the degree of the data of continuation is a filter corresponding sampling points number;

E1) from the pulse after the discretization cause and effect, read in the sampling number certificate of sending pulse, then normalization is carried out in the transmission pulse of sampled point and handled, the normalized factor is an evolution of the cycle of each wideband data symbol going up the corresponding sampling points number;

F1) data behind the periodic extension are carried out windowing operation, promptly multiply each other with the corresponding sampling point that disperses of data after the filter after the normalization and the continuation, then with the accumulator of storing in data correspondingly add up mutually;

G1) data in the accumulator are carried out the shift left operation of the sample value length on the symbol period length of broadband;

H1) initialized cyclic variable is carried out 1 add up certainly, judges whether the modulation operations of symbol on all subcarriers having been carried out then, if output modulation done state sign then, otherwise just jump to step D1) repeat above operating process.

The method of the multicarrier demodulation that is provided according to a fifth aspect of the invention, may further comprise the steps:

A2) symbolic variable is carried out adding up certainly, and will grow the register zero setting of ordering for K;

B2) from the discretization device of broadband, read sampling point data after the discretization, once reading current location is the data of filter point to the length of back location;

C2) put the sample value that reads receiving filter into and carry out normalization from received pulse discretization cause and effect makeup, the normalized factor is the evolution of the number of samples on the symbol lengths;

D2) receiving filter after the normalization that obtains being carried out corresponding sampling point with the broadband sampling point data of reading filter length into multiplies each other;

E2) data after the windowing of the filter length point that obtains are counted by subcarrier carry out segmentation, each segment data that will be divided into then adds up;

F2) data after will adding up are carried out FFT and are calculated fast, generate the data on the parallel demodulated subcarrier of multichannel;

G2) export the multidiameter delay subcarrier data of demodulation;

H2) will add up variable certainly from adding 1, judge then whether demodulation finishes, if finish then export demodulation done state sign; Do not finish if; Then turn back to step D2, repeat above process, till the broadband sampling point data that all are received are carried out whole demodulation.

Above-mentioned first to the 5th aspect also has following technical characterictic:

Described pulse to be sent or received pulse are received and dispatched the mutual ambiguity function A of pulse below satisfying _{G, γ}(P, Q) select in the impulse function of condition:

$A_{g,\mathrm{\γ}}(P,Q)=\left\{\begin{array}{cc}1,& (P,Q)=\left(\mathrm{0,0}\right)\\ 0,& (P,Q)\∉\left(\mathrm{0,0}\right)\end{array}\right.$

Wherein, P is through the symbol shift value behind the channel; Q is through the subcarrier shift value behind the channel.

The processing of described discretization cause and effect comprises processing of pulse discretization and the processing of pulse cause and effect, and wherein said pulse discretization is handled and is: use inverse/one of sample rate to carry out discretization for basic chronomere to sending pulse.

The processing of said pulse cause and effect is: be the even number of samples point if pulse is long, then for half the sampled point that pulse is moved right, if pulse is the odd number sampled point, then subtract the half the sampled point after 1 for pulse length that pulse is moved right.

The present invention can effectively solve problems such as the outer leakage of band energy is too big in traditional OFDM multicarrier modulation system, PAPR is too high; The present invention not only is suitable for the narrower multicarrier system of the more subcarrier bandwidth of sub-carrier number; And being applicable to the multicarrier system of the less subcarrier bandwidth broad of sub-carrier number, this system can be applicable to the communication of uplink and downlink simultaneously.

Below in conjunction with accompanying drawing principle of the present invention, structure and operation principle are elaborated.

Description of drawings

Fig. 1 is multi-carrier modulation, demodulating equipment block diagram;

Fig. 2 is a multi-carrier modulation Rapid Realization installation drawing;

Fig. 3 is a multi-carrier modulation Rapid Realization installation drawing.

Embodiment

At first principles of modulation and demodulation of the present invention is elaborated.

The continuous complex baseband signal of the multicarrier of transmission of the present invention can be expressed as:

$s\left(t\right)=\underset{l=-\∞}{\overset{\∞}{\mathrm{\Σ}}}\underset{k=0}{\overset{K-1}{\mathrm{\Σ}}}{a}_k\left(l\right)g(t-\mathrm{lT})e^{j2\mathrm{\πkF}(t-\mathrm{lT})}=\underset{l=-\∞}{\overset{\∞}{\mathrm{\Σ}}}\underset{k=0}{\overset{K-1}{\mathrm{\Σ}}}{a}_k\left(l\right)g_{l,k}\left(t\right)---\left(1\right)$

Wherein, K is the number of subcarrier, a _k(l) be expressed as transmission data on l the symbol on the k number of sub-carrier, g (t) transmitting filter, F is the interval of each subcarrier.g _{L, k}(t)=g (t-lT) e ^{J2 π kF (t-lT)}The time-frequency displacement of expression transmitting filter.

The demodulation of l symbol is output as on the receiving terminal k number of sub-carrier:

$b_k\left(l\right)={\∫}_{t}r\left(t\right){\mathrm{\γ}}_{l,k}^{*}\left(t\right)\mathrm{dt}---\left(2\right)$

Here r (t) is the continuous baseband complex signal that receives, and γ (t) is a received pulse, and the frequency displacement position is γ at that time _{L, k}(t)=γ (t-lT) e ^{J2 π kF (t-lT)}, T is a symbol period.

The demodulation expression-form that receives signal is:

$b_l\left(k\right)=\underset{t}{\∫}r\left(t\right)\·{\mathrm{\γ}}^{*}(t-\mathrm{lT})e^{-j2\mathrm{\πkF}(t-\mathrm{lT})}\mathrm{dt}=\underset{l^{\′}=-\∞}{\overset{+\∞}{\mathrm{\Σ}}}\underset{k^{\′}=0}{\overset{M-1}{\mathrm{\Σ}}}{a}_{l^{\′}}\left(k^{\′}\right)e^{j2\mathrm{\πFT}(l-l^{\′})k}{A}_{g,\mathrm{\γ}}(l^{\′}-l,k-k^{\′})---\left(3\right)$

Wherein $A_{g,\mathrm{\γ}}(P,Q)=\underset{t}{\∫}g\left(t\right){\mathrm{\γ}}^{*}(t+\mathrm{PT})e^{-j2\mathrm{\π\; QFt}}\mathrm{Dt},$ Mutual ambiguity function for the transmitting-receiving pulse.

When transmitting-receiving, pulse are satisfied

$A_{g,\mathrm{\γ}}(P,Q)=\left\{\begin{array}{cc}1,& (P,Q)=\left(\mathrm{0,0}\right)\\ 0,& (P,Q)\∉\left(\mathrm{0,0}\right)\end{array}\right.---\left(4\right)$

B is arranged _l(k)=a _l(k), can realize the modulation and demodulation of complete ground, the transmitting-receiving pulse of claim to satisfy condition (4) is the pulse of normalization biorthogonal.(4) are the pulse that we need as long as the transmitting-receiving pulse satisfies condition.The pulse of satisfying this condition has: root raised cosine pulse, raised cosine pulse, sinc pulse etc.

The transmission signal of formula (1) has after with the sample rate discretization:

$s\left(n\right)=\underset{l=-\∞}{\overset{\∞}{\mathrm{\Σ}}}\underset{k=0}{\overset{K-1}{\mathrm{\Σ}}}{a}_k\left(l\right)g(n-\mathrm{lN})e^{j2\mathrm{\π}\frac{k}{K}(n-\mathrm{lN})}---\left(5\right)$

Here N=T/F _s, F _sSample rate for system.

If pulse is a non-causalization, after carry out cause and effectization, paired pulses has:

$s\left(n\right)=\underset{l=0}{\overset{\∞}{\mathrm{\Σ}}}{s}_l(n-\mathrm{lN})---\left(6\right)$

$s_l\left(n\right)=s_l(p-L/2)=g(p-L/2)\underset{k=0}{\overset{K-1}{\mathrm{\Σ}}}{a}_k^{\′}\left(l\right)e^{j2\mathrm{\π}\frac{k}{K}p}---\left(7\right)$

Wherein L is the length of filter, more than for the length of filter is the situation of even number, when the length of filter has during for odd number:

$s_l\left(n\right)=s_l(p-(L-1)/2)=g(p-(L-1)/2)\underset{k=0}{\overset{K-1}{\mathrm{\Σ}}}{a}_k^{\′}\left(l\right)e^{j2\mathrm{\π}\frac{k}{K}p}---\left(7a\right)$

More than operation require filter length L/2 (when the even number) or (L-1)/2 (for odd number time) be the integral multiple of sub-carrier number K.

The signal generative process of following formula (6) (7) can be used fast algorithm implementation.

Likewise to the reception signal of formula (2), with having after the sample rate discretization:

$b_k\left(l\right)=\underset{m=-L/2}{\overset{L/2-1}{\mathrm{\Σ}}}r(m+\mathrm{lN}){\mathrm{\γ}}^{*}\left(m\right)e^{-j2\mathrm{\π}\frac{k}{K}m}---\left(8\right)$

When L is even number.

$b_k\left(l\right)=\underset{m=-(L-1)/2}{\overset{(L-1)/2}{\mathrm{\Σ}}}r(m+\mathrm{lN}){\mathrm{\γ}}^{*}\left(m\right)e^{-j2\mathrm{\π}\frac{k}{K}m}---\left(8a\right)$

When L is odd number.

Corresponding when pulse is even number:

$b_k\left(l\right)=\underset{p=0}{\overset{L-1}{\mathrm{\Σ}}}r(p+\mathrm{lN}-L/2){\mathrm{\γ}}^{*}(p-L/2)e^{-j2\mathrm{\π}\frac{k}{K}p}---\left(9\right)$

Corresponding when pulse is odd number:

$b_k\left(l\right)=\underset{p=0}{\overset{L-1}{\mathrm{\Σ}}}r(p+\mathrm{lN}-(L-1)/2){\mathrm{\γ}}^{*}(p-(L-1)/2)e^{-j2\mathrm{\π}\frac{k}{K}p}---\left(9a\right)$

The signal demodulating process of following formula (9) can be used fast algorithm implementation.

Below in conjunction with accompanying drawing the details of the present invention and the course of work are elaborated.

Fig. 1 is multi-carrier modulation, demodulation implement device block diagram.As shown in Figure 1, the data on each number of sub-carrier that at first will be to be modulated are mapped to K by device 100 ₀On the number of sub-carrier.Here K ₀Be the subcarrier number that is used, the sub-carrier number of use can be whole available sub-carrier number K _a, also can be whole available sub-carrier number K _aIn a part, the concrete method of salary distribution is operated by the sub-carrier number of the actual use of system, K counts for DFT altogether, fills out symbol 0 above the subcarrier that can not be used.The makeup of transmission pulse discretization cause and effect is put 101 and is used for the transmission impulse function of conitnuous forms is realized discretization, if pulse is a non-causal then, then again with the non-causal pulse cause and effectization after the discretization.Use g ₀(t) expression continuous impulse, discretization is the sample frequency F with system _sTo the continuous impulse g that samples ₀(n)=g ₀(n/F _s), n=0 ..., L-1, L are the length of filter, its numerical values recited need combine the moulding factor of concrete pulse to confirm that through analysis and emulation sending pulse here is a part that realizes modulation, and cause and effectization is meant the non-causal pulse, g when L is even number (n)=g ₀(n-L/2), g (n)=g when L is odd number ₀(n-(L-1)/2).Device 102 is passed in transmission pulse after the discretization cause and effectization that produces on data of distributing on each number of sub-carrier in the device 100 and the device 101 in the lump, then in the modulation of 102 li realizations of subcarrier-modulated module to each subcarrier data.The transmission impulse function here can be a kind of in the qualified moulding pulse; Like root raised cosine filter (SRRC); Gaussian pulse (Gauss); Han Mite pulse (Hermite) etc., will there be the molding parameter of different adjustment impulse waveforms in the different pulse function, and the size of parameter needs the subcarrier spacing of coupling system design and the mask of three dB bandwidth and out of band spectrum decay to confirm jointly.The process of modulation is the process that the data-modulated on each K number of sub-carrier of separating is formed broadband signal in 102 devices, and its Rapid Realization algorithm will further be introduced in the back.In device 103, be output as modulated broadband serial data stream after modulation is accomplished, the data flow time corresponding is spaced apart sample rate F _s

Further, the multicarrier serial data stream after ovennodulation becomes analog signal (these modules are not shown) after through analog-to-digital conversion and frequency up-conversion operation, sends at the corresponding original device of the open close mistake of emission then.Simulated and the process of transmitting of whole baseband signal can be regarded the process of baseband signal through signal equivalently as.The concrete form of channel is relevant with the media that signal post adopts; If wire communication then channel be concrete medium; The channel response corresponding like media such as telephone wire, optical fiber, twisted-pair feeders; If transmitting the media of signal is the radio in eating dishes without rice or wine, then channel is aerial pairing concrete communication environment.No matter be through which kind of media, channel strip can illustrate with device 104.

Device 105 is to be used for receiving discretization wideband data device, and this part mainly is that the broadband analog signal that receives is carried out the discretization operation, samples like AD etc.Sample rate then is the sample rate F of system design less _sInteger speed (can be 1 times), following explanation all is to be single baseband sampling rate F doubly by sample rate _sDescribe.Device 106 is put for the makeup of received pulse discretization cause and effect, and the effect of this device and transmitter installation 101 are identical, are that received pulse is operated just here.Same, use γ ₀(t) continuous function of expression received pulse, discretization is the sample frequency F with system _sTo the continuous impulse γ that samples ₀(n)=γ ₀(n/F _s), n=0 ..., L-1, L are the length of filter, and its numerical values recited need combine to send pulse to be confirmed, and then the length scale with the transmission pulse is identical simultaneously with sending pulsion phase when received pulse.And cause and effectization is to the non-causal pulse, γ when L is even number (n)=γ ₀(n-L/2), γ (n)=γ when L is odd number ₀(n-(L-1)/2).Received pulse normally with meet and send off the pulse that pulse has photograph album character, received pulse is confirmed by following expression formula: ∫ g (t) γ (t-lT) e ^{-j2 π kF (t-lT)}Dt=δ _lδ _k, g (t) is the continuous function that sends pulse here, and r (t) is the continuous function of received pulse, and F is a subcarrier spacing, and T is a symbol period, δ is the unit impact response function.107 is the subcarrier demodulation device, in order to realize the rectification of broadband signal to sub-carrier signal, is the inverse process of device 102, and it can use fast algorithm implementation, and the Rapid Realization device will combine Fig. 3 further to introduce in the back.The 108th, subcarrier data is separated mapping device, and it is the inverse process of device 100, obtains the corresponding data of each user in order to realization from the data on each number of sub-carrier that demodulates, and separates the process of mapping and is undertaken by the anti-process of subcarrier data mapping mode.

Introduce the Rapid Realization device of modulation below in conjunction with Fig. 2.Fig. 2 is the flow chart of multi-carrier modulation Rapid Realization device, also is the Rapid Realization device of the device of 102 among Fig. 1.200 is apparatus for initializing, i.e. l=0, s _l(n)=0, n ∈ [0, L-1], l is a corresponding symbol sequence number on the subcarrier here.201 for reading the data symbol a on the subcarrier _k(l) device, the data here pass over from 100 modules, also are the last l of subcarrier k data symbol to be modulated.Deliver to device 202 from 201 data and be the IFFT that K orders and obtain b (n), that is: calculate b (n)=KIFFT (a _k(l)), 0≤n≤K-1 wherein, 0≤k≤K-1.The b that calculates (n) is delivered to device 203 does periodic extension, promptly c (n)=[b (n), b (n) ... .], 0≤n≤L-1 obtains c (n).Device 204 obtains modulating pulse from 101, needs simultaneously normalization is carried out in pulse, promptly $p\left(n\right)=g\left(n\right)/\sqrt{N},$ N ∈ [0, L-1], N is F for symbol period T carries out sample rate here _sSampling after the sampling number that obtains.205 for the windowing adding up device, is about to the data that device 203 obtains and carries out windowing and overlap-add operation, that is: s _l(n)=s _l(n)+and c (n) p (n), n ∈ [0, L-1].In device 206, export s then _l(n) preceding N point data s (m)=s (n+lN)=s _l(n), n ∈ [0, N-1], m ∈ [lN, lN+N-1] is the N point wideband data that l moment baseband transmit signals is exported this moment.Further, in device 207, realizing moves to left upgrades operation, with s _l(n) move to left N point and upgrade, that is: $s_l\left(n\right)=\left\{\begin{array}{cc}{s}_l(n+N),& n\∈[0,L-N-1]\\ 0,& n\∈[L-N,L-1]\end{array}\right..$ In the device 208 variable l is added up 1 certainly, promptly l=l+1 judges then whether modulation finishes; If finish then forward submodule 209 to, output modulation end mark, otherwise; Then turn back to device 202 and repeat above process, all symbols on subcarrier are all realized modulation.

Fig. 3 is for realizing the device for carrying out said figure of wideband data rectification.Device 300 is realized initialization operations, i.e. l=0, r _Sum(n)=0,0≤n≤K.Device 301 is from installing 105 reading of data, be the wideband data that reads after the discretization, r _l(n)=and r (n+lN), n ∈ [0, L-1], the discretization wideband data of r (n) for obtaining in the device 105.Device 302 reads the reception modulating pulse and implements the normalization operation from installing 106, promptly $p\left(n\right)={\mathrm{\γ}}^{*}(n-L/2)/\sqrt{N},$ N ∈ [0, L-1].Device 303 realizes carrying out windowing from installing 301 data obtained with device 302, i.e. c (n)=p (n) r _l(n), n ∈ [0, L-1].Device 304 is realized the segmentations operation that adds up, promptly $r_{\mathrm{Sum}}\left(n\right)=\underset{i=0}{\overset{M-1}{\mathrm{\Σ}}}c(n+\mathrm{IK}),$ N ∈ [0, K-1], M=floor (L/K), floor () are downward round numbers function r _Sum(n)=r _Sum(n)+and c (n), n ∈ [KM, L-1].Device 305 is realized the FFT Fast transforms, promptly $b_l\left(k\right)=\underset{n=0}{\overset{K-1}{\mathrm{\Σ}}}{r}_{\mathrm{Sum}}\left(n\right)e^{-j2\mathrm{\π}\frac{k}{K}n},$ K ∈ [0, K-1].Device 306 is exported demodulation subcarrier data, promptly exports the data b of K parallel subcarrier _l(k).In device 307, upgrade cyclic variable further, promptly l=l+1 judges then whether demodulation finishes; If finish then forward submodule 308 to, output demodulation end mark, otherwise; Then turn back to device 303 and repeat above process, up to the modulated symbols that demodulates on all subcarriers.

The above is merely preferred embodiment of the present invention, is not to be used to limit protection scope of the present invention.

Claims (8)

1. multi-carrier modulation method may further comprise the steps:

Data map to be sent to a plurality of subcarriers, is formed the parallel duplex subcarrier data;

The pulse discretization is carried out in pulse to be sent handle and the processing of pulse cause and effect, obtain discretization cause and effect transmission pulse signal;

Utilize discretization cause and effect transmission pulse that said parallel duplex subcarrier data is carried out the modulation of multidiameter delay subcarrier data, be generated as one tunnel modulated broadband serial data stream thus;

Export described modulated broadband serial data stream;

Wherein, said pulse discretization is handled and is: the sample frequency with system is sampled to continuous impulse;

Wherein, the processing of said pulse cause and effect is: be the even number of samples point if pulse is long, then for half the sampled point that pulse is moved right, if pulse is the odd number sampled point, then subtract the half the sampled point after 1 for pulse length that pulse is moved right; And

Wherein, said pulse to be sent is received and dispatched the mutual ambiguity function A of pulse below satisfying _{G, γ}(P, Q) select in the impulse function of condition:

$A_{g,\mathrm{\γ}}(P,Q)=\left\{\begin{array}{cc}1,& (P,Q)=\left(\mathrm{0,0}\right)\\ 0,& (P,Q)\∉\left(\mathrm{0,0}\right)\end{array}\right.$

Wherein, P is through the symbol shift value behind the channel; Q is through the subcarrier shift value behind the channel.

2. multi-carrier modulation method according to claim 1, wherein:

The bandwidth of said subcarrier is greater than 10kHz; And

The number of subcarriers that is used for uplink is less than the number of subcarriers that is used for downlink transfer.

3. multi-carrier modulation device comprises:

The subcarrier data mapping device is used for data map to be sent to a plurality of subcarriers, forms the parallel duplex subcarrier data;

Send the makeup of pulse discretization cause and effect and put, be used for that the pulse discretization is carried out in pulse to be sent and handle and the processing of pulse cause and effect, obtain discretization cause and effect transmission pulse signal;

The subcarrier-modulated device is used for utilizing discretization cause and effect transmission pulse that said parallel duplex subcarrier data is carried out the modulation of multidiameter delay subcarrier data, is generated as one tunnel modulated broadband serial data stream thus;

Output modulated wideband data device is used for exporting described modulated broadband serial data stream;

Wherein, pulse discretization is handled: the sample frequency with system is sampled to continuous impulse;

Wherein, the processing of pulse cause and effect is: be the even number of samples point if pulse is long, then for half the sampled point that pulse is moved right, if pulse is the odd number sampled point, then subtract the half the sampled point after 1 for pulse length that pulse is moved right;

Wherein, said pulse to be sent is received and dispatched the mutual ambiguity function A of pulse below satisfying _{G, γ}(P, Q) select in the impulse function of condition:

$A_{g,\mathrm{\γ}}(P,Q)=\left\{\begin{array}{cc}1,& (P,Q)=\left(\mathrm{0,0}\right)\\ 0,& (P,Q)\∉\left(\mathrm{0,0}\right)\end{array}\right.$

Wherein, P is through the symbol shift value behind the channel; Q is through the subcarrier shift value behind the channel.

4. multi-carrier modulation device according to claim 3, wherein, said pulse discretization is handled and is: use inverse/one of sample rate for basic chronomere received pulse to be carried out discretization.

5. realize may further comprise the steps the method for subcarrier-modulated by the described multi-carrier modulation device of claim 3 for one kind:

A1) to symbolic variable and the variable that adds up certainly carry out initialization operation;

B1) from the multidiameter delay subcarrier data that the subcarrier data mapping device generates, read as data to be modulated;

C1) to the IFFT Fast transforms of the multidiameter delay subcarrier data that reads;

D1) to many doubling times continuation of the data after the quick change of IFFT, the degree of the data of continuation is a filter corresponding sampling points number;

F1) from the pulse after the discretization cause and effect, read in the sampling number certificate of sending pulse, then normalization is carried out in the transmission pulse of sampled point and handled, the normalized factor is an evolution of the cycle of each wideband data symbol going up the corresponding sampling points number;

F1) data behind the periodic extension are carried out windowing operation, promptly multiply each other with the corresponding sampling point that disperses of data after the filter after the normalization and the continuation, then with the accumulator of storing in data correspondingly add up mutually;

G1) data in the accumulator are carried out the shift left operation of the sample value length on the symbol period length of broadband;

H1) initialized cyclic variable is carried out 1 add up certainly, judges whether the modulation operations of symbol on all subcarriers having been carried out then, if output modulation done state sign then, otherwise just jump to step D1) repeat above operating process.

6. multicarrier rectification device comprises:

Receive discretization wideband data device, be used for obtaining receiving serial bandwidth carrier data sampling and the discretization processing by the integral multiple of sample rate through the broadband serial data stream behind the channel;

The makeup of received pulse discretization cause and effect is put, and is used for that received pulse is carried out the pulse discretization and handles and the processing of pulse cause and effect, obtains discretization cause and effect received pulse signal;

Subcarrier de system device is used for utilizing discretization cause and effect received pulse signal that said reception serial bandwidth carrier data are carried out data demodulates, obtains the parallel duplex subcarrier data;

Subcarrier data is separated mapping device, is used for said parallel duplex subcarrier data is separated mapping treatment, obtains the corresponding data of each user;

Wherein, said pulse discretization is handled and is: the sample frequency with system is sampled to continuous impulse;

Wherein, the processing of pulse cause and effect is: be the even number of samples point if pulse is long, then for half the sampled point that pulse is moved right, if pulse is the odd number sampled point, then subtract the half the sampled point after 1 for pulse length that pulse is moved right;

Wherein, said received pulse is received and dispatched the mutual ambiguity function A of pulse below satisfying _{G, γ}(P, Q) select in the impulse function of condition:

$A_{g,\mathrm{\γ}}(P,Q)=\left\{\begin{array}{cc}1,& (P,Q)=\left(\mathrm{0,0}\right)\\ 0,& (P,Q)\∉\left(\mathrm{0,0}\right)\end{array}\right.$

Wherein, P is through the symbol shift value behind the channel; Q is through the subcarrier shift value behind the channel.

7. multi-carrier demodulation device according to claim 6, wherein, said pulse discretization is handled and is: use inverse/one of sample rate for basic chronomere received pulse to be carried out discretization.

8. realize may further comprise the steps the method for subcarrier demodulation by the described multicarrier rectification of claim 6 device for one kind:

A2) symbolic variable is carried out adding up certainly, and will grow the register zero setting of ordering for K;

B2) from receive discretization wideband data device, read sampling point data after the discretization, once reading current location is the data of filter point to the length of back location;

C2) put the sample value that reads receiving filter into and carry out normalization from received pulse discretization cause and effect makeup, the normalized factor is the evolution of the number of samples on the symbol lengths;

D2) receiving filter after the normalization that obtains being carried out corresponding sampling point with the broadband sampling point data of reading filter length into multiplies each other;

E2) data after the windowing of the filter length point that obtains are counted by subcarrier carry out segmentation, each segment data that will be divided into then adds up;

F2) data after will adding up are carried out FFT and are calculated fast, generate the data on the parallel demodulated subcarrier of multichannel;

G2) export the multidiameter delay subcarrier data of demodulation;

H2) will add up variable certainly from adding 1, judge then whether demodulation finishes, if finish then export demodulation done state sign; Do not finish if; Then turn back to step D2, repeat above process, till the broadband sampling point data that all are received are carried out whole demodulation.

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