CN101204030A - Quadrature frequency-division and time-division transmitter, receiver and method thereof - Google Patents

Quadrature frequency-division and time-division transmitter, receiver and method thereof Download PDF

Info

Publication number
CN101204030A
CN101204030A CNA2005800499220A CN200580049922A CN101204030A CN 101204030 A CN101204030 A CN 101204030A CN A2005800499220 A CNA2005800499220 A CN A2005800499220A CN 200580049922 A CN200580049922 A CN 200580049922A CN 101204030 A CN101204030 A CN 101204030A
Authority
CN
China
Prior art keywords
oftdm
data
sequence
symbol
channel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CNA2005800499220A
Other languages
Chinese (zh)
Inventor
张小东
卜智勇
周斌
李明齐
杨秀梅
周平
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Institute of Microsystem and Information Technology of CAS
Shanghai Research Center for Wireless Communications
Original Assignee
Shanghai Institute of Microsystem and Information Technology of CAS
Shanghai Research Center for Wireless Communications
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Institute of Microsystem and Information Technology of CAS, Shanghai Research Center for Wireless Communications filed Critical Shanghai Institute of Microsystem and Information Technology of CAS
Publication of CN101204030A publication Critical patent/CN101204030A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2626—Arrangements specific to the transmitter only
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
    • H04L25/03006—Arrangements for removing intersymbol interference
    • H04L25/03159—Arrangements for removing intersymbol interference operating in the frequency domain

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

Techniques are provided to support orthogonal multiple carriers frequency-time division multiplex based on orthogonal frequency division multiplex and single carrier with frequency domain equalization in prior art. At a transmitter end, Serial to Parallel Transform and Inverse Fast Fourier Transform are performed for the input serial data stream, then data blocks after IFFT are multiplexed to be a OFTDM symbol data part in temporal sequence; and then a circulation prefix is added in its front-part to form a final OFTDM symbol. At a receiver end, the CP in the front-part of the OFTDM symbol down-converted to a baseband is removed, and after the operations of data de-multiplex, FFT and P/S corresponding to the transmitter end are performed, the original serial data stream is recovered. Except for including the advantage of said prior art, this disclosure can overcome their disadvantage, and a preferable tradeoff between the general performance and complexity of the system can be acquired.

Description

A kind of quadrature frequency-division and time-division transmitter, receiver and method thereof
Technical field
The present invention relates to wireless communication technology, relate in particular to a kind of technology of in wireless communication system, coming transmission signals by a plurality of quadrature carriers.
Background technology
In wireless communication system, especially in wide-band mobile communication system, the aerial signal transmission technology is just becoming the focus of research.Higher in order to obtain, for example up to 10bps/Hz's, spectrum efficiency, support the communication requirement of several scenes, support various adaptive control technologies, the signal transmission technology of wide-band mobile communication system must be supported more any similar technology more performance than in the past, keeps controllable implementation complexity simultaneously.Now, the signal transmission technology of wide-band mobile communication is mainly based on OFDM (OFDM) technology, and derive various mutation technology, as OFDMA (OFDM), MC-CDMA (multi-carrier-wave-CDMA), MT-CDMA (multitone-code division multiple access), VSF-OFCDM (orthogonal frequency code division multiplexing) etc., in addition, also be subjected to people's attention and attention based on the generalized multi-carrier modulation technique (GMC) of bank of filters and the enhancement techniques CP-CDMA (Cyclic Prefix-code division multiple access) of traditional C DMA etc.
Yet, the performance of comprehensive existing these transmission technologys, they all show superior performance under certain conditions, but, the scene that is suitable for is still broad inadequately, and for example, the symbol lengths of OFDM technology, CP length and the availability of frequency spectrum are directly related, influenced its adaptability design, and this shortcoming has also been arranged by other technology that it derives out different terrain and mobile scene; And single-carrier technology is not enough for the adaptability of channel frequency domain as technology such as CP-CDMA, has directly influenced its frequency diversity performance; And place GMC technology between OFDM technology and the single-carrier technology, then do not possess inherence the technology such as resembling OFDM and CP-CDMA, to the adaptability of channel time-frequency plane, seeming on implementation complexity, artificial trace is very heavy, design is nature inadequately, simultaneously, also there is the same with the OFDM technology, the relatively poor shortcoming of scene adaptability in it.
Mainly contain two kinds of OFDM and SC/FDE (single carrier-frequency domain equalization) with the closely-related technology of the present invention, they have represented two kinds of different information transferring methods respectively: multi-carrier communication and single carrier communication.
OFDM (OFDM) is a kind of multi-carrier modulation technology; it adopts parallel transmission; the high-speed data that transmitted decomposed and be modulated in the subchannel (frequency domain) of a plurality of overlapping but quadratures; make the cycle of each modulation signal expand greater than multidiameter delay; if between modulation symbol, increase the protection interval of certain width; then the intersymbol interference that causes of multipath transmission is eliminated basically; therefore ofdm system has the very high availability of frequency spectrum; the intersymbol interference that transmission causes to multipath has very strong robustness, can support high speed data transfer.
The symbol sebolic addressing that this wireless multi-carrier communications method of OFDM will transmit is mapped to the transmission of getting on of parallel a plurality of subcarriers; In transmission course, the symbol on each subcarrier only is its corresponding subchannel amplitude-frequency response weighting, and gaussian additive noise pollutes; At receiver side, need only amplitude-frequency response normalizing with subchannel, just can estimate the symbol that sends on the subcarrier, thereby estimate the transmission sequence.For the ease of in the receiver side amplitude-frequency response characteristic of balanced subchannel nondestructively, must be added into the Cyclic Prefix (CP) of the youthful and the elderly's degree at the front end that each OFDM sends symbol for the expansion of channel maximum delay, it is that tail end copy from the OFDM symbol comes.
Fig. 1 is the block diagram of OFDM transmitting set of the prior art and receiver.Wherein, transmitting set 1 ' comprises a string and conversion equipment 11 ', is used for the serial symbol stream string that the mapping through data-modulated is obtained and is converted to a plurality of parallel symbol streams; An IFFT converting means 12 ' is used for by being modulated to described a plurality of parallel symbol streams on a plurality of orthogonal sub-carriers against the IDFT conversion and synthesizing the OFDM symbol; One adds CP device 13 ', be used for the part of described OFDM symbol afterbody is copied to the front end of symbol, form the OFDM symbol of final band CP, CP has periodically the symbol that is transmitted, when the length of CP longer than signal transmission delay time in channel, then intersymbol interference (ISI) only can influence the CP of OFDM symbol front end, thereby can simply just can eliminate ISI by removing CP at receiver end.Certainly, this transmitting set also should comprise: the chnnel coding and the modulating device that are used for the data of input are carried out chnnel coding and data-modulated; And the OFDM symbol carried out D/A conversion and analog (for example channel shaping filter), and be modulated to radio frequency, go out by antenna transmission then, because these parts there is no direct relation with the present invention, so for simplicity's sake, in this omission.
Correspondingly, in receiver 2 ', comprise that is removed a CP device 21 ', the CP that is used for being down-converted to the OFDM symbol front end that base band obtains removes; A FFT device 22 ' is used for coming the OFDM symbol behind the removal CP is carried out correlation demodulation by the DFT conversion parallel symbol stream after the acquisition demodulation; One and go here and there conversion equipment 23 ', the parallel symbol stream and the string that are used for institute's demodulation is obtained are converted to serial symbol stream.Certainly, this wireless receiver machine also should comprise the reception antenna of received RF signal; Radiofrequency signal is down-converted to the down-conversion device of base band and the baseband signal after the down-conversion is carried out matched filter of matched filtering etc.; And, chnnel coding and modulating rule based on transmitting terminal come described serial symbol stream is carried out corresponding channel decoding and demodulation, thereby obtain the channel decoding and the demodulating equipment of the signal flow of original transmission, because these parts and the present invention there is no direct relation, therefore for simplicity's sake, in this omission.
Compare with the carrier wave communication system of traditional receiver based on the transversal filter framework, the implementation complexity of ofdm system low (realize the sub-channel signal shaping and receive matched filtering) based on IFFT/FFT, the spectrum efficiency height, be convenient to the application in system of broadband wireless communication, but, the growth of the CP length that the availability of frequency spectrum of OFDM and power efficiency comprise in OFDM along with CP and descending, and, for the availability of frequency spectrum and the power efficiency that keeps higher level, have to ratio with the length of the transmission data block of OFDM symbol and CP length (for example remains on more than certain multiple, be at least 4 times), like this, just directly caused the number of subcarriers of OFDM symbol under the broadband wireless communications scene, (for example generally to present bigger numerical value, 256 subcarriers), cause the equivalent bandwidth of subcarrier to be far smaller than the coherence bandwidth of channel, promoted the susceptibility of receiver, and reduced the frequency diversity performance of ofdm system the Frequency Synchronization precision; Simultaneously, because of the time domain stack of big quantity subcarrier has caused the lifting significantly that sends signal peak-to-average ratio, improved the index request of transmitter again to power amplification phase Linearity.In a word, though OFDM is stronger to the adaptability of channel time-frequency plane, but, its symbol design length is subjected to the influence of the availability of frequency spectrum too big, subcarrier in frequency domain is divided rich redundant, is unfavorable for very much using in the communication scenes fast in translational speed, that carrier frequency is high, Doppler (Doppler) frequency displacement is big; Otherwise, in the communication scenes that move at low speed, carrier frequency is low, the Doppler frequency displacement is little, the length of OFDM symbol can not suitably extend again, to promote the availability of frequency spectrum, therefore, the design of whole OFDM system seems more stiff, and its symbol lengths must design at the abominable scene of communication scenes, thereby has caused potential capacitance loss.
SC/FDE (single carrier frequency domain equalization) communication system and traditional carrier wave communication system are very approaching, but, it is divided into a piece data blocks in equal with the symbol sebolic addressing that sends, and be that each data block copies a Cyclic Prefix (CP), the design principle of this CP is analogous to OFDM ofdm system of the present invention, and different is that data to be copied are afterbodys of each data block.Like this, receiver side just can carry out equilibrium to channel is corresponding based on frequency-domain equilibrium method, thereby repairs the damage of channel to the transmission symbol, and then estimates corresponding transmission symbol sebolic addressing.SC/FDE system implementation complexity low (receiving terminal is finished frequency domain equalization based on FFT/IFFT conversion and single-point zero forcing equalization device), complete equalizer design criterion is arranged, signal peak-to-average ratio is not high, the Design of length of CP and data block is more flexible, be convenient to the application in system of broadband wireless communication, still, this design for scheme does not have the adaptability of consideration to the channel time-frequency characteristic, cause receiver to be difficult to offer the bigger frequency diversity gain of channel decoding, combination property is not high; Simultaneously, the consequence that the single carrier receiving algorithm causes noise to strengthen and spread easily, this also can have a strong impact on the reception error performance of system.
The present invention proposes in order to solve the above-mentioned problems in the prior art just.
Summary of the invention
The present invention is a kind of novel orthogonal multiple carrier frequency-division and time-division technology-OFTDM that proposes on the basis of comprehensive various traditional single carriers and multi-carrier transmission technology pluses and minuses.
Transmitting set of the present invention at first will be transformed into the sequence of blocks of data of respective length through a plurality of parallel stream of modulation symbols after string and the conversion based on invert fast fourier transformation (IFFT), and it is multiplexing that a plurality of data blocks through the IFFT conversion are carried out data block according to time sequencing, is an OFTDM (orthogonal frequency-time division multiplexing) symbol data part with a plurality of definition data blocks after multiplexing; Secondly, with a plurality of data copies of the afterbody of this OFTDM symbol data part,,, thereby generate this OFTDM symbol to the forefront of this OFTDM symbol data part as Cyclic Prefix (CP) part; Once more, the part (data division and CP part) to the OFTDM symbol carries out the channel shaping filter; At last, the baseband signal of OFTDM system is transformed into radio frequency (RF) signal, and is radiated wireless channel by antenna system and gets on.
Wireless receiver of the present invention at first is transformed into baseband signal with the wireless signal that receives, and carries out matched filtering to received signal, finishes symbol timing and Frequency Synchronization; Subsequently, remove the Cyclic Prefix of OFTDM symbol front end, the data division to the OFTDM symbol carries out demultiplexing again, reverts to a plurality of sequence of blocks of data the same with transmitting terminal length; At last, based on the FFT Fourier transform transmitting terminal data block is mapped as corresponding stream of modulation symbols.Preferably, also can be before the demultiplexing that carries out OFTDM symbol data part, based on channel estimating, realize partly to offer the demultiplexing step through the OFTDM symbol data of frequency domain equalization again by OFTDM other frequency domain equalization of symbol level (FDE) with the positive inverse-Fourier transform of FFT/IFFT of the data division equal in length of OFTDM symbol, channel equalizer etc.
Preferably, in transmitting set of the present invention, the following control method that the number of IFFT transformation matrix size, circulating prefix-length and data block demultiplexing is adjusted of being used for is proposed also:
1) adjusts the size of the transformation matrix of described IFFT converting means according to channel width and channel delay length;
2) adjust the length of described Cyclic Prefix according to the size of the length of channel delay expansion and IFFT transformation matrix, make it more than or equal to the length of channel delay expansion with smaller or equal to the size of described IFFT transformation matrix; Also promptly, Cyclic Prefix (CP) must be greater than channel expansion length; Transmitter IFFT transform length is at least greater than CP length (remaining unchanged in communication process);
3) correspondingly adjust the quantity of transmitter IFFT transform data piece time-domain multiplexed with the size variation of Doppler (Doppler) frequency displacement (perhaps channel coherence time), so that the equivalent time length of its OFTDM symbol is less than described channel length coherence time.
According to a first aspect of the invention, a kind of transmitting set that is used in wireless communication system by a plurality of quadrature carrier transmission signals is provided, comprise: go here and there and conversion equipment for one, be used for the string character data sequence string that to import and change a plurality of parallel symbol data sequences; An IFFT converting means is used for described a plurality of parallel symbol data sequences are carried out the IFFT orthogonal transform, generates a plurality of time-domain data blocks; It is characterized in that, also comprise: a data block multiplexer is used for the OFTDM symbol data sequence that is multiplexed with base band by the sequencing of rise time through a plurality of time-domain data blocks after the IFFT orthogonal transform with described; With a protection interval adding set, be used at the protection interval of the OFTDM of described base band symbol data sequence header or afterbody generation length-specific, to generate base band OFTDM signal waiting for transmission.
According to a second aspect of the invention, a kind of method that is used for sending by a plurality of quadrature carriers signals in the transmitting set of wireless communication system is provided, and it may further comprise the steps: with the string character data sequence string of input and change a plurality of parallel symbol data sequences; Described a plurality of parallel symbol data sequences are carried out the IFFT orthogonal transform, generate a plurality of time-domain data blocks; With the described OFTDM symbol data sequence that is multiplexed with base band through a plurality of time-domain data blocks after the IFFT orthogonal transform by the sequencing of rise time; Protection interval at the OFTDM of described base band symbol data sequence header or afterbody interpolation length-specific.
According to a third aspect of the invention we, provide a kind of wireless receiver that is used to receive by the OFTDM signal of a plurality of quadrature carrier transmission in wireless communication system, it comprises: a protection interval removal device is used for removal and transforms to Base bandHave between the protection OFTDM symbol sebolic addressing at interval protection at interval; A data block Deplexing apparatus, being used for described removal protection OFTDM symbol sebolic addressing demultiplexing at interval is a plurality of sequence of blocks of data; A FFT converting means is used for by the sequencing of time of reception described a plurality of data blocks being carried out the FFT conversion, and it is transformed to a plurality of parallel symbol data sequences; With one and go here and there conversion equipment, be used for described a plurality of parallel symbol data sequences are transformed to the string character data sequence.
Preferably, described wireless receiver also comprises: a channel estimating apparatus is used for coming the channel response of time domain is estimated according to the described OFTDM symbol sebolic addressing that transforms to base band, to obtain the estimated value of channel response; In the time of one/and the frequency converting means, be used for protecting OFTDM sequence of blocks of data at interval to be transformed to the OFTDM sequence of blocks of data of frequency domain described removal; A frequency-domain equalizer is used for the estimated value based on described channel response, comes the described OFTDM sequence of blocks of data that is transformed frequency domain is carried out the phase compensation and the amplitude compensation of channel impairments, to obtain the frequency domain OFTDM sequence of blocks of data through frequency domain equalization; One frequency/time converting means, be used for being the OFTDM sequence of blocks of data of time domain with remapping through the frequency domain OFTDM sequence of blocks of data of frequency domain equalization, be transferred to described data block Deplexing apparatus.
According to a forth aspect of the invention, provide a kind of method that is used to receive by the OFTDM signal of a plurality of quadrature carrier transmission in the wireless receiver of wireless communication system, it may further comprise the steps: remove Base bandThe protection of OFTDM symbol at interval; With described removal protection OFTDM symbol sebolic addressing demultiplexing at interval is a plurality of sequence of blocks of data; Sequencing by time of reception carries out the FFT conversion to described a plurality of data blocks, and it is transformed to a plurality of parallel symbol data sequences; With, be the string character data sequence with described a plurality of parallel data symbol sebolic addressing parallel serial conversions.
Preferably, described method of reseptance is further comprising the steps of: come the channel response of time domain is estimated according to described OFTDM symbol sebolic addressing or the pilot tone training sequence that transforms to base band, to obtain the estimated value of channel response; Described removal protection OFTDM sequence of blocks of data at interval is transformed to the OFTDM sequence of blocks of data of frequency domain; Based on the estimated value of described channel response, come the described OFTDM sequence of blocks of data that is transformed frequency domain is carried out the phase compensation and the amplitude compensation of channel impairments, to obtain frequency domain OFTDM sequence of blocks of data through frequency domain equalization; Be the OFTDM sequence of blocks of data of time domain with remapping through the frequency domain OFTDM sequence of blocks of data of frequency domain equalization, be used to carry out described data block de-multiplex operation.
Transmitting set of the present invention and receiver are combination and the expansion scheme of tradition based on a kind of novelty of the ofdm system (OFDM) of Cyclic Prefix (CP) and single-carrier frequency domain equalization system (SC/FDE), both had the low implementation complexity of OFDM, the advantage of spectral efficient, the advantage that the frequency displacement that has SC/FDE again is sane, be easy to Frequency Synchronization; Both had the reception error performance characteristic that is equal to OFDM, had the translational speed accommodation more much bigger again than OFDM.Based on the OFTDM technical scheme, can be on a kind of communication system integrated multi-carrier communication and single carrier communication interior simultaneously in advantage, simultaneously, can avoid their deficiency again as far as possible, make overall system performance and complexity reach compromise preferably.
More specifically, compared with prior art, the present invention had both had the frequency spectrum adaptability of multi-carrier transmission technology (as OFDM), had the flexibility of single carrier communication again, and suitable with the OFDM technology on transmission performance, and implementation complexity is lower.What is more important, by controlling transmitter the size of IFFT transform data piece time-domain multiplexed quantity, system can obtain bigger throughput gain, the translational speed adaptability that scope is broad more; By size based on channel coherence bandwidth design transmitter IFFT conversion, frequency displacement robustness that can elevator system; By introducing the CP prefix, can make OFTDM keep system and OFDM similarly sane performance aspect timing.
Description of drawings
Describe the present invention the identical parts of wherein same or analogous Reference numeral representative with reference to the accompanying drawings.
Fig. 1 is the block diagram of OFDM transmitting set of the prior art and receiver.
Fig. 2 is used for block diagram via the transmitting set of orthogonal multiple carrier transmission signals for the embodiment according to the present invention in the wide-band mobile communication network;
Fig. 3 is used for flow chart via the radio transmission method of orthogonal multiple carrier transmission signals for the embodiment according to the present invention in the wide-band mobile communication network;
Fig. 4 is the organigram that has added the OFTDM symbol sebolic addressing of Cyclic Prefix;
Fig. 5 is used for block diagram via the wireless receiver of orthogonal multiple carrier transmission signals for the embodiment according to the present invention in the wide-band mobile communication network;
Fig. 6 is used for flow chart via the method for wireless reception of orthogonal multiple carrier transmission signals for the embodiment according to the present invention in the wide-band mobile communication network;
Fig. 7 shows the emulation schematic diagram based on the MATLAB/SIMULink emulation platform;
Fig. 8 is illustrated on the emulation platform shown in Figure 6 three kinds of schemes such as the OFDM of OFTDM scheme of the present invention and prior art and SC/FDE scheme are carried out results' (error rate) that simulation calculating obtains under following simulation parameter condition.
Embodiment
Below with reference to accompanying drawing, and in conjunction with specific embodiments the present invention is described in detail.Should be appreciated that the present invention is not limited to specific embodiment.
Fig. 2 illustrate according to a present invention embodiment at cordless communication network, especially be used for sending the block diagram of the transmitting set 1 of signals in the wide-band mobile communication network by a plurality of quadrature carriers.Comprising a channel coding device 11, digital modulation device 12, string and conversion equipment 13, contrary Fourier (IDFT) converting means 14, data block multiplexer 15, protection adding set 16, shaping filter device 17, a RF converter plant 18 and a transmitting antenna 19 at interval.
Need to prove that the channel coding device shown in Fig. 2, digital modulation device, shaping filter device, RF converter plant and transmitting antenna and purpose of the present invention there is no direct relation, only, be described in the lump at this as a preferred implementation.
Suppose { a k, k=0,1,2....} is the output Serial No. of input transmitting set, comes transmitting set of the present invention is elaborated below with reference to Fig. 2 and in conjunction with Fig. 3:
Channel coding device 11 is used to adopt predetermined chnnel coding rule to come input data sequence { a k, k=0,1, the 2....} chnnel coding is transformed into dateout sequence { b with it k, k=0,1,2....}, the cascaded code that wherein said chnnel coding rule can adopt for example RS sign indicating number and convolution code to form, Turbo code, perhaps LDPC sign indicating number, the also adaptive coding scheme that can form for multiple technologies is as adaptive coding and modulating scheme (AMC);
Digital modulation device 12 is used for, for example according to the Gray coding criterion, the dot chart that will be mapped to modulation symbol through the data sequence of chnnel coding gets on, selected modulation system is determined by system design, can be defined as a kind of in BPSK, QPSK, the qam mode, also can be for according to the error rate with carry and disturb than adaptively selected multiple dynamic modulation mode.Through digital modulation device 12, input data sequence { b k, k=0,1,2....} is transformed into output symbol sequence { d k, k=0,1,2....};
Serial/parallel conversion equipment 13 is used for string character sequence that digital modulation mapping is obtained and is divided into a plurality of string character data blocks according to the size of thereafter IFFT transformation matrix, and described a plurality of string character data blocks are gone here and there and conversion operations, to form corresponding a plurality of parallel symbol data block.Through serial/parallel conversion equipment 13, the string character sequence { d of input k, k=0,1,2....} is transformed into a plurality of parallel symbol data piece { e k, k=0,1,2....}, here, e kRepresent a column vector that number of elements is the same with the IFFT transform size;
Contrary Fourier (IDFT) converting means 14, preferably, can realize by contrary fast fourier transform (IFFT) module, be used for each parallel symbol data block of input is carried out the IDFT conversion, generate corresponding a plurality of time-domain symbol data piece, wherein this IDFT conversion is equal to the parallel data of described input is carried out orthogonal multiple carrier modulation and synthetic, through the IFFT conversion module, and the sequence of blocks of data { e that input is parallel k, k=0,1,2 ... be transformed into corresponding time-domain data blocks sequence { f k, k=0,1,2 ..., relation is each other obeyed f k=IFFT (e k), here, f kAlso represent a column vector that number of elements is the same with the IFFT transform size;
Data block multiplexer 15 is used for the data block after the process IFFT conversion of given number is multiplexed into according to the precedence that produces the data division of the longer orthogonal frequency division and time division multiplexing of length (OFTDM) symbol.Multiplexing through data block, the sequence of blocks of data { f of input k, k=0,1,2 ... be transformed into the sequence { g of the data division of OFTDM symbol k, k=0,1,2 ..., here, g kRepresent a number of elements and the equirotal column vector of OFTDM symbol data part;
Protection at interval adding set 16 is used for OFTDM after multiplexing through data block) the head or tail portion of symbol data part add a length-specific protection at interval, be used to reduce interchannel interference (length at this protection interval should greater than channel maximum delay extension length).Preferably; protection adding set at interval can be adopted Cyclic Prefix (CP) adding set; a part that also is about to described OFTDM symbol data part afterbody copies to the front end of OFTDM symbol data part; form the OFTDM symbol of final band CP; CP has periodically the symbol that is transmitted; when the length of CP longer than the maximum delay time that signal transmits in channel; then intersymbol interference (ISI) only can influence the CP of OFTDM symbol front end, thereby can simply just can eliminate ISI by removing CP at receiver end.Through Cyclic Prefix adding set, list entries { g k, k=0,1,2 ... be transformed into complete OFTDM symbol sebolic addressing { h k, k=0,1,2 ..., here, h kRepresent a column vector that number of elements is the same with the OFTDM symbol size, its organigram as shown in Figure 4;
Channel signal building mortion 17 is used for forming filtering according to spectrum mask to sent the OFTDM signal waveform.Through signal shaping device 17, the OFTDM symbol sebolic addressing { h of input k, k=0,1,2 ... be transformed into output waveform sequence { i k, k=0,1,2 ...;
RF converting means 18 is used for the OFTDM symbol sebolic addressing of base band is transformed into radiofrequency signal, and via transmission antennas transmit in wireless channel.
Preferably, transmitting set 1 also comprises control device 19 (not shown)s, is used to carry out following function:
1) adjusts the size of the transformation matrix of described IFFT converting means according to channel width and channel delay length;
2) adjust the length of described Cyclic Prefix according to the size of the length of channel delay expansion and IFFT transformation matrix, make it more than or equal to the length of channel delay expansion with smaller or equal to the size of described IFFT transformation matrix; Also promptly, Cyclic Prefix (CP) must be greater than channel expansion length; Transmitter IFFT transform length is at least greater than CP length (remaining unchanged in communication process);
3) size variation with Doppler (Doppler) frequency displacement (perhaps channel coherence time) becomes the quantity that oppositely enlarges or dwindle transmitter IFFT time-domain multiplexed; And adjust the multiplexing quantity of described data block according to channel length coherence time, so that the equivalent time length of its OFTDM symbol is less than described channel length coherence time.
Fig. 3 is used for flow chart via the radio transmission method of orthogonal multiple carrier transmission signals for the embodiment according to the present invention in the wide-band mobile communication network.
Need to prove, step and this nothing of purpose direct relation of the present invention of the chnnel coding step shown in Fig. 2, digital modulation step, shaping filter step, RF frequency conversion step and emission wireless signal, only, be described in the lump at this as a preferred implementation.
Equally, suppose { a k, k=0,1,2....} is the output Serial No. of input transmitting set;
In step S101, adopt the predetermined channel coding rule to come to input data sequence { a k, k=0,1, the 2....} chnnel coding is transformed into dateout sequence { b with it k, k=0,1,2....}, the cascaded code that wherein said chnnel coding rule can adopt for example RS sign indicating number and convolution code to form, Turbo code, perhaps LDPC sign indicating number, the also adaptive coding scheme that can form for multiple technologies is as adaptive coding and modulating scheme (AMC);
In step S102, for example according to the Gray coding criterion, the dot chart that will be mapped to modulation symbol through the data sequence of chnnel coding gets on, selected modulation system is determined by system design, can be defined as a kind of in BPSK, QPSK, the qam mode, also can be for according to the error rate with carry and disturb than adaptively selected multiple dynamic modulation mode.Through modulation operations, input data sequence { b k, k=0,1,2....} is transformed into output symbol sequence { d k, k=0,1,2....};
In step S103, string character sequence after the symbol-modulated is divided into a plurality of string character data blocks according to the size of thereafter IFFT transformation matrix, and described a plurality of string character data blocks are gone here and there and conversion operations, to form corresponding a plurality of parallel symbol data block.Through serial/parallel conversion operations, the string character sequence { d of input k, k=0,1,2....} is transformed into a plurality of parallel symbol data piece { e k, k=0,1,2....}, here, ek represents a column vector that number of elements is the same with the IFFT transform size;
In step S104, each parallel symbol data block to input is carried out the IDFT conversion, generate corresponding a plurality of time-domain symbol data piece (wherein this IDFT conversion be equal to the parallel data of described input is carried out orthogonal multiple carrier modulation and synthetic), preferably, the IDFT conversion can be realized by contrary fast fourier transform (IFFT) algorithm.Through the IFFT map function, the sequence of blocks of data { e that input is parallel k, k=0,1,2 ... be transformed into corresponding time-domain data blocks sequence { f k, k=0,1,2 ..., relation is each other obeyed f k=IFFT (e k), here, f kAlso represent a column vector that number of elements is the same with the IFFT transform size;
In step S105, the data block after the process IFFT conversion of given number is multiplexed into the data division of the longer orthogonal frequency division and time division multiplexing of length (OFTDM) symbol according to the precedence that produces.Through the multiplexing operation of data block, the sequence of blocks of data { f of input k, k=0,1,2 ... be transformed into the sequence { g of the data division of OFTDM symbol k, k=0,1,2 ..., here, g kRepresent a number of elements and the equirotal column vector of OFTDM symbol data part;
In step S106, through the OFTDM of data block after multiplexing) the head or tail portion of symbol data part add a length-specific protection at interval, be used to reduce interchannel interference (length at this protection interval should greater than channel maximum delay extension length).Preferably; protection is spaced apart Cyclic Prefix (CP); also be; the part of described OFTDM symbol data part afterbody is copied to the front end of OFTDM symbol data part; form the OFTDM symbol of final band CP, CP has periodically the symbol that is transmitted, when the length of CP longer than the maximum delay time that signal transmits in channel; then intersymbol interference (ISI) only can influence the CP of OFTDM symbol front end, thereby can simply just can eliminate ISI by removing CP at receiver end.Add step, list entries { g through Cyclic Prefix k, k=0,1,2 ... be transformed into complete OFTDM symbol sebolic addressing { h k, k=0,1,2 ..., here, h kRepresent a column vector that number of elements is the same with the OFTDM symbol size, its organigram as shown in Figure 4;
In step S107, form filtering to sent the OFTDM signal waveform according to spectrum mask.Through signal shaping operation, the OFTDM symbol sebolic addressing { h of input k, k=0,1,2 ... be transformed into output waveform sequence { i k, k=0,1,2 ...;
In step S108, the OFTDM symbol sebolic addressing of base band is transformed into radiofrequency signal;
In step S109, via transmission antennas transmit in wireless channel.
Preferably, radio transmission method of the present invention also comprises following controlled step:
1) adjusts the size of the transformation matrix of described IFFT converting means according to channel width and channel delay length;
2) adjust the length of described Cyclic Prefix according to the size of the length of channel delay expansion and IFFT transformation matrix, make it more than or equal to the length of channel delay expansion with smaller or equal to the size of described IFFT transformation matrix; Also promptly, Cyclic Prefix (CP) must be greater than channel expansion length; Transmitter IFFT transform length is at least greater than CP length (remaining unchanged in communication process);
3) correspondingly enlarge or dwindle the quantity of transmitter IFFT time-domain multiplexed with the size variation of Doppler (Doppler) frequency displacement (perhaps channel coherence time); And adjust the multiplexing quantity of described data block according to channel length coherence time, so that the equivalent time length of its OFTDM symbol is less than described channel length coherence time.
Fig. 5 be according to the present invention an embodiment at cordless communication network, especially be used to receive block diagram in the wide-band mobile communication network via the wireless receiver 2 of the signal of a plurality of quadrature carriers transmission.Wherein, wireless receiver comprise matched filtering/synchronizer 21, protection at interval removal device 22, channel estimating apparatus 23, frequently/time converting means 24, single-point frequency domain equalization device 25, the time/frequency converting means 26, data block Deplexing apparatus 27, FFT converting means 28, parallel/serial converting means 29, decoding device 30, channel code translator 31.
Wherein, need to prove that the matched filter, decoding device, channel code translator and the purpose of the present invention that are used for Base-Band Processing there is no direct relation, only as a preferred implementation, are described in the lump at this.In addition, wireless receiver also should comprise the radio frequency converter plant that is used to receive the reception antenna of wireless signal and is used for wireless signal is down-converted to base band, and they and purpose of the present invention do not have direct relation yet, and be because for simplicity's sake, not shown in the drawings.
Suppose that wireless receiver 2 can obtain a baseband signal { l through reception antenna and RF radio frequency modular converter k, k=0,1,2 ....Below, come wireless receiver of the present invention is elaborated with reference to Fig. 5 and in conjunction with Fig. 6:
Matched filtering and synchronizer 21 are used for the baseband signal that receives is carried out matched filtering, simultaneously, finish the Time and Frequency Synchronization function of received signal.Through matched filtering and synchronizer 21, input data sequence { l k, k=0,1,2 ... be transformed into dateout sequence { m k, k=0,1,2 ...;
Protection removal device 22 at interval is used to remove the protection interval that is added on the OFTDM symbol sebolic addressing.When protection was spaced apart Cyclic Prefix, it was used to remove the Cyclic Prefix (CP) of OFTDM symbol front end, thereby can eliminate the intersymbol interference of OFTDM.Through removing Cyclic Prefix, input data sequence { m k, k=0,1,2 ... be transformed into output block sequence { n k, k=0,1,2 ..., here, n kRepresent the same column vector of FFT transform size among a number of elements and the 3-5;
Channel estimating apparatus 23 is used for channel response being estimated in time domain based on described OFTDM symbol sebolic addressing or pilot tone training sequence.Through channel estimating apparatus 23, can obtain the estimated value { w of channel response k, k=0,1,2 ... L-1}, here, L is the maximum delay of time-domain response;
The time/time-domain data blocks that frequency converting means 24 is used for the certain-length that will be received transforms to frequency domain, so that frequency-domain equalizer can be eliminated the influence of channel to this data block, particularly, the time/the frequency converting means can realize by DFT, FFT conversion scheduling algorithm.Through out-of-date/frequency converting means, input block sequence { n k, k=0,1,2 ... be transformed into output block sequence { o k, k=0,1,2 ..., relation is each other obeyed o k=FFT (n k), here, o kRepresent a column vector that number of elements is the same with the FFT transform size;
The channel estimation value that frequency domain equalization device 25 is used for being provided based on channel estimating apparatus 23 at frequency domain the OFTDM symbol data of described removal Cyclic Prefix carries out the phase place and the amplitude compensation of channel impairments.Wherein, the frequency domain equalization device can adopt single-point frequency domain least mean-square error MMSE equalizer or single-point frequency domain zero forcing equalization device.Particularly, if finish frequency domain equalization, then pass through frequency domain equalization device 25, output block sequence { p by single-point ZF (ZF) method k, k=0,1,2 ... and input block sequence { o k, k=0,1,2 ... between the pass be: p k=diag{[1/W 0, 1/W 1..., 1/W L-1] o k, here, diag () expression is to the diagonalization operation of certain vector, [W 0W 1W L-1] T=FFT (w), and latter w=[w 0w 1W L-1] T, i.e. channel response column vector.
Frequently/time converting means 26 be used for just returning to time domain through the frequency domain subband signal of frequency domain equalization is synthetic so that further handle, particularly, frequently/time converting means can pass through IDFT, IFFT conversion scheduling algorithm is realized.Through overfrequency/time converting means 26, input block sequence { p k, k=0,1,2 ... be transformed into output block sequence { q k, k=0,1,2 ..., here, q k=IFFT (p k), and, p kAnd q kThe expression number of elements column vector the same with the IFFT transform size;
Data block Deplexing apparatus 27 is used for the data block identical with the data division size of the OFTDM symbol of transmitting set end demultiplexed into the sequence of blocks of data identical with transmitting set end IFFT transformation matrix size.Through data block Deplexing apparatus 27, the OFTDM symbol data { q of input k, k=0,1,2 ... be transformed into a plurality of sequence of blocks of data { r k, k=0,1,2 ..., here, r kRepresent a number of elements and the same column vector of transmitter terminal IFFT transform size;
Be used for described a plurality of symbol data pieces are carried out the inverse operation of answering with transmitter terminal IFFT transfer pair with the equirotal FFT converting means 28 of transformation matrix of above-mentioned OFTDM transmitter terminal IFFT converting means, be used for the time-domain data blocks of input is remapped to frequency domain.Through FFT converting means 28, input OFTDM sequence of blocks of data { r k, k=0,1,2 ... be transformed into parallel symbol data piece piece sequence { s k, k=0,1,2 ..., s kRepresent a column vector that number of elements is the same with the FFT transform size;
Parallel/serial converting means 29 is used for the parallel symbol sequence of blocks of data of input is transformed into the symbol data sequence of serial.Through parallel/serial converting means 29, the symbol data piece sequence { s of input k, k=0,1,2 ... be transformed into serial data sequence { t k, k=0,1,2 ...;
Digital demodulating apparatus 30 is used for according to the Gray coding rule of transmitter terminal the data sequence of importing being demodulated to the corresponding digital sequence.If the channel decoding algorithm of be about to carrying out will be based on the hard decision input information, then Shu Chu hard information Serial No. is { 0} and the { random alignment of 1}, otherwise symbol demodulation device 30 will provide accordingly based on the soft message digit sequence of counting bit quantization.Through digital demodulating apparatus 30, the data sequence { t of input k, k=0,1,2 ... be transformed into the digital information { u of output k, k=0,1,2 ...;
Channel code translator 31 is used for carrying out the channel decoding algorithm based on the chnnel coding rule of transmitter terminal.Through channel code translator 31, input digit sequence { u k, k=0,1,2 ... be transformed into and export Serial No. { v k, k=0,1,2 ....
Fig. 6 is used for flow chart via the method for wireless reception of orthogonal multiple carrier transmission signals for the embodiment according to the present invention in the wide-band mobile communication network.
Need to prove, the step of the reception wireless signal shown in the figure, wireless signal is down-converted to step, matched filtering step, digital demodulation step, channel decoding step and this nothing of purpose direct relation of the present invention of base band, only, be described in the lump at this as a preferred implementation.
Wherein, in step S201, receive wireless signal by reception antenna;
In step S202, wireless signal is down-converted to base band OFTDM signal, suppose through receiving step and down-conversion step, obtain base band OFTDM signal { l k, k=0,1,2 ...;
In step S203, the base band OFTDM signal that receives is carried out matched filtering, simultaneously, finish the Time and Frequency Synchronization function of received signal.Through matched filtering and synchronizing step, input data sequence { l k, k=0,1,2 ... be transformed into OFTDT symbol data sequence { m k, k=0,1,2 ...;
In step S204, remove the protection interval that is added on the OFTDM symbol sebolic addressing.When protection was spaced apart Cyclic Prefix, it was used to remove the Cyclic Prefix (CP) of OFTDM symbol front end, thereby can eliminate the intersymbol interference of OFTDM.Through described removal Cyclic Prefix step, input data sequence { m k, k=0,1,2 ... be transformed into output block sequence { n k, k=0,1,2 ..., here, nk represents the same column vector of FFT transform size among a number of elements and the 3-5;
In step S205, channel response is estimated in time domain based on described OFTDM symbol sebolic addressing or pilot tone training sequence, to obtain channel estimation value { w k, k=0,1,2 ... L-1}, here, L is the maximum delay of time-domain response;
In step S206, the reception data block of certain-length transformed in the frequency domain go, so that can eliminate the influence of channel to this data block by frequency domain equalization, particularly, this step can realize by DFT, FFT conversion scheduling algorithm.Through out-of-date/frequency switch process, input block sequence { n k, k=0,1,2 ... be transformed into output block sequence { o k, k=0,1,2 ..., relation is each other obeyed o k=FFT (n k), here, o kRepresent a column vector that number of elements is the same with the FFT transform size;
In step S207, be used for based on above-mentioned channel estimation value, come the OFTDM symbol data of described removal Cyclic Prefix to be carried out the phase place and the amplitude compensation of channel impairments at frequency domain by the single-point frequency domain equalization.Wherein, the frequency domain equalization device can adopt single-point frequency domain least mean-square error MMSE equalizer or single-point frequency domain zero forcing equalization device.Particularly, if finish frequency domain equalization, then through frequency domain equalization operation, output block sequence { p by single-point ZF (ZF) method k, k=0,1,2 ... and input block sequence { o k, k=0,1,2 ... between the pass be: p k=diag{[1/W 0, 1/W 1..., 1/W L-1] o k, here, diag () expression is to the diagonalization operation of certain vector, [W 0W 1W L-1] T=FFT (w), and latter w=[w 0w 1W L-1] T, i.e. channel response column vector.
In step S208, will go through synthetic the returning in the time domain of the frequency domain subband signal of frequency domain equalization, so that further handle, particularly, it can pass through IDFT, IFFT conversion scheduling algorithm is realized.Through overfrequency/time converting means 26, input block sequence { p k, k=0,1,2 ... be transformed into output block sequence { q k, k=0,1,2 ..., here, q k=IFFT (p k), and, p kAnd q kThe expression number of elements column vector the same with the IFFT transform size;
In step S209, the data block identical with the OFTDM symbol data part size of transmitting set end demultiplexed into and the identical sequence of blocks of data of transmitting set end IFFT transformation matrix size.Through described data block demultiplexing step, input OFTDM symbol data sequence { q k, k=0,1,2 ... be transformed into a plurality of symbol data piece sequence { r k, k=0,1,2 ..., here, r kRepresent a number of elements and the same column vector of transmitter terminal IFFT transform size;
In step S210, by coming described a plurality of symbol data pieces are carried out the inverse operation of answering with transmitter terminal IFFT transfer pair, be used for the time-domain data blocks of input is remapped to frequency domain with the equirotal FFT transformation matrix of above-mentioned OFTDM transmitter terminal IFFT transformation matrix.Through described FFT shift step, a plurality of OFTDM symbol data piece sequence { r of input k, k=0,1,2 ... be transformed into a plurality of parallel symbol data piece piece sequence { s k, k=0,1,2 ..., s kRepresent a column vector that number of elements is the same with the FFT transform size;
In step S211, with the parallel/serial symbol data sequence that is transformed into serial of parallel symbol sequence of blocks of data of input.Through parallel/serial map function, a plurality of symbol data piece sequence { s of input k, k=0,1,2 ... be transformed into serial data sequence { t k, k=0,1,2 ...;
In step S212, the data sequence of input is demodulated to the corresponding digital sequence according to the Gray coding rule of transmitter terminal.If the channel decoding algorithm of be about to carrying out will be based on the hard decision input information, then Shu Chu hard information Serial No. be 0} and the random alignment of 1}, otherwise, will output accordingly based on the soft message digit sequence of counting bit quantization.Through symbol demodulation step, the data sequence { t of input k, k=0,1,2 ... be transformed into the digital information { u of output k, k=0,1,2 ...;
In step S213, carry out the channel decoding algorithm based on the chnnel coding rule of transmitter terminal.Through channel decoding step, input digit sequence { u k, k=0,1,2 ... be transformed into and export Serial No. { v k, k=0,1,2 ....
Fig. 7 shows the emulation schematic diagram based on the MATLAB/SIMULink emulation platform;
Fig. 8 is illustrated on the emulation platform shown in Figure 6 three kinds of schemes such as the OFDM of OFTDM scheme of the present invention and prior art and SC/FDE scheme are carried out results' (error rate) that simulation calculating obtains under following simulation parameter condition, as seen from Figure 7, the error rate of OFTDM of the present invention obviously is better than the error rate of SC/FDE scheme, suitable with the error rate of OFDM, but because realization complexity of the present invention (256 subcarriers) is because OFDM (2048 subcarriers), so the present invention has obtained a good compromise between performance and implementation complexity.
It is as follows to set the simulated environment parameter:
Channel width: 10M, channel model: SUI-4, chnnel coding: convolution code (coding: code check 1/2, constraint length 7, generator polynomial [171,133], decoding: 8 grades of 3bit quantize Viterbi soft decoding, decoding depth 34)
The initialization system simulation parameter:
OFTDM subcarrier number: 256, the multiplexing number of data block: 8, frequency domain equalization is counted: 2048, frequency-domain equilibrium method: single-point ZF (ZF) equalizer
Set and participate in system parameters relatively:
OFDM：
The subcarrier number: 2048, frequency domain equalization is counted: 2048, frequency-domain equilibrium method: single-point ZF (ZF) equalizer;
SC-FDE/LE：
Frequency domain equalization is counted: 2048, and frequency-domain equilibrium method: single-point ZF (ZF) equalizer;
Emulation schematic diagram based on the MATLAB/SIMULink emulation platform:
More than specific embodiments of the invention are described.Need to understand being, the present invention is not limited to above-mentioned specific for execution mode, and those skilled in the art can make various distortion or modification within the scope of the appended claims.

Claims (18)

1. transmitting set that is used in wireless communication system by a plurality of quadrature carrier transmission signals comprises:
Go here and there and conversion equipment for one, be used for the string character data sequence string that to import and change a plurality of parallel symbol data sequences;
An IFFT converting means is used for described a plurality of parallel symbol data sequences are carried out the IFFT orthogonal transform, generates a plurality of time-domain data blocks;
It is characterized in that, also comprise:
A data block multiplexer is used for the OFTDM symbol data sequence that is multiplexed with base band by the sequencing of rise time through a plurality of time-domain data blocks after the IFFT orthogonal transform with described; With
A protection interval adding set is used at the protection interval of the OFTDM of described base band symbol data sequence header or afterbody generation length-specific, to generate base band OFTDM signal waiting for transmission.
2. transmitting set according to claim 1 is characterized in that, also comprises:
Described protection adding set at interval is a Cyclic Prefix generating apparatus; it is used for the specific quantity data with the afterbody of described OFTDM symbol data sequence; as Cyclic Prefix, copy to the head of described OFTDM data sequence, generate quadrature frequency-division and time-division symbol sebolic addressing with Cyclic Prefix.
3. transmitting set according to claim 1 and 2 is characterized in that, also comprises:
A control device also is used for according to channel width, and channel coherence bandwidth and channel delay length are adjusted the size of the transformation matrix of described IFFT converting means.
4. transmitting set according to claim 3 is characterized in that,
Described control device also is used for adjusting according to the size of the length of channel delay expansion and IFFT transformation matrix the length of described Cyclic Prefix, makes it more than or equal to the length of channel delay expansion with smaller or equal to the size of described IFFT transformation matrix.
5. transmitting set according to claim 4 is characterized in that,
Described control device also is used for correspondingly adjusting the multiplexing quantity of described data block with the size variation of Doppler frequency shift or channel coherence time, so that the equivalent time length of its OFTDM symbol is less than described channel length coherence time.
6. method that in the transmitting set of wireless communication system, is used for sending signals by a plurality of quadrature carriers, it may further comprise the steps:
With the input string character data sequence string and change a plurality of parallel symbol data sequences;
Described a plurality of parallel symbol data sequences are carried out the IFFT orthogonal transform, generate a plurality of time-domain data blocks;
With the described OFTDM symbol data sequence that is multiplexed with base band through a plurality of time-domain data blocks after the IFFT orthogonal transform by the sequencing of rise time;
Protection interval at the OFTDM of described base band symbol data sequence header or afterbody interpolation length-specific.
7. according to the method for claim 6, it is characterized in that described generation protection step at interval comprises:
Specific quantity data with the afterbody of described OFTDM symbol data sequence as Cyclic Prefix, copy to the head of described OFTDM symbol data sequence, generate the OFTDM symbol sebolic addressing with Cyclic Prefix.
8. according to claim 6 or 7 described methods, it is characterized in that, also comprise the steps:
Adjust the size of the transformation matrix of described IFFT converting means according to channel width and channel delay length.
9. method according to claim 8 is characterized in that,
Adjust the length of described Cyclic Prefix according to the size of the length of channel delay expansion and IFFT transformation matrix, make its length more than or equal to the channel delay expansion, length with adjust the transformation matrix of described IFFT converting means smaller or equal to the size adaptation ground of described IFFT transformation matrix makes its length more than or equal to described Cyclic Prefix.
10. method according to claim 9 is characterized in that, and is further comprising the steps of:
Correspondingly adjust the quantity of described IFFT converting means with the size variation of Doppler shift or channel coherence time, so that the equivalent time length of its OFTDM symbol is less than described channel length coherence time
11. a wireless receiver that is used to receive in wireless communication system by the OFTDM signal of a plurality of quadrature carrier transmission, it comprises
A protection interval removal device is used to remove the protection interval between the OFTDM symbol sebolic addressing with protection interval that transforms to base band;
A data block Deplexing apparatus, being used for described removal protection OFTDM symbol sebolic addressing demultiplexing at interval is a plurality of sequence of blocks of data;
A FFT converting means is used for by the sequencing of time of reception described a plurality of data blocks being carried out the FFT conversion, and it is transformed to a plurality of parallel symbol data sequences;
One and go here and there conversion equipment, be used for described a plurality of parallel symbol data sequences are transformed to the string character data sequence.
12. wireless receiver according to claim 11 is characterized in that, also comprises
A channel estimating apparatus is used for coming the channel response of time domain is estimated according to the described OFTDM symbol sebolic addressing that transforms to base band, to obtain the estimated value of channel response;
In the time of one/and the frequency converting means, be used for protecting OFTDM sequence of blocks of data at interval to be transformed to the OFTDM sequence of blocks of data of frequency domain described removal;
A frequency-domain equalizer is used for the estimated value based on described channel response, comes the described OFTDM sequence of blocks of data that is transformed frequency domain is carried out the phase compensation and the amplitude compensation of channel impairments, to obtain the frequency domain OFTDM sequence of blocks of data through frequency domain equalization;
One frequency/time converting means, be used for being the OFTDM sequence of blocks of data of time domain with remapping through the frequency domain OFTDM sequence of blocks of data of frequency domain equalization, be transferred to described data block Deplexing apparatus.
13. according to claim 11 or 12 described wireless receivers, it is characterized in that,
Described frequency-domain equalizer comprises: single-point frequency domain least mean-square error MMSE equalizer.
14. according to claim 11 or 12 described wireless receivers, it is characterized in that,
Described frequency-domain equalizer is a single-point frequency domain zero forcing equalization device.
15. a method that is used to receive in the wireless receiver of wireless communication system by the OFTDM signal of a plurality of quadrature carrier transmission, it may further comprise the steps:
Remove the protection interval of base band OFTDM symbol;
With described removal protection OFTDM symbol sebolic addressing demultiplexing at interval is a plurality of sequence of blocks of data;
Sequencing by time of reception carries out the FFT conversion to described a plurality of data blocks, and it is transformed to a plurality of parallel symbol data sequences;
With described a plurality of parallel data symbol sebolic addressing parallel serial conversions is the string character data sequence.
16. method according to claim 15 is characterized in that, and is further comprising the steps of:
Come the channel response of time domain is estimated according to described OFTDM symbol sebolic addressing or the pilot tone training sequence that transforms to base band, to obtain the estimated value of channel response;
Described removal protection OFTDM sequence of blocks of data at interval is transformed to the OFTDM sequence of blocks of data of frequency domain;
Based on the estimated value of described channel response, come the described OFTDM sequence of blocks of data that is transformed frequency domain is carried out the phase compensation and the amplitude compensation of channel impairments, to obtain frequency domain OFTDM sequence of blocks of data through frequency domain equalization;
Be the OFTDM sequence of blocks of data of time domain with remapping through the frequency domain OFTDM sequence of blocks of data of frequency domain equalization, be used to carry out described data block de-multiplex operation.
17. according to claim 15 or 16 described methods, it is characterized in that,
Described frequency domain equalization step is a single-point frequency domain least mean-square error MMSE equalization methods.
18. according to claim 15 or 16 described methods, it is characterized in that,
Described frequency domain equalization step is a single-point frequency domain zero forcing equalization method.
CNA2005800499220A 2005-05-25 2005-05-25 Quadrature frequency-division and time-division transmitter, receiver and method thereof Pending CN101204030A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2005/000726 WO2006125343A1 (en) 2005-05-25 2005-05-25 A orthogonal frequency-time division multiplex transmitter, a receiver and methods

Publications (1)

Publication Number Publication Date
CN101204030A true CN101204030A (en) 2008-06-18

Family

ID=37451623

Family Applications (1)

Application Number Title Priority Date Filing Date
CNA2005800499220A Pending CN101204030A (en) 2005-05-25 2005-05-25 Quadrature frequency-division and time-division transmitter, receiver and method thereof

Country Status (2)

Country Link
CN (1) CN101204030A (en)
WO (1) WO2006125343A1 (en)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101534278B (en) * 2009-04-10 2011-08-17 北京大学 Time-frequency expansion Orthogonal Frequency Division Multiplexing transmitting and receiving device, method and system
CN103325232A (en) * 2013-07-08 2013-09-25 北京新岸线移动多媒体技术有限公司 Terminal control realization method and system and terminal equipment
CN103973611A (en) * 2013-01-25 2014-08-06 普天信息技术研究院有限公司 Frequency deviation correction method
CN106597384A (en) * 2016-12-21 2017-04-26 中国航空工业集团公司雷华电子技术研究所 OFDM (Orthogonal Frequency Division Multiplexing) modulation based constant envelope waveform generation circuit
WO2017071574A1 (en) * 2015-10-30 2017-05-04 华为技术有限公司 Method and device for sending data
CN107171999A (en) * 2017-06-13 2017-09-15 电子科技大学 A kind of method for ofdm system feature suppression
CN107710708A (en) * 2015-06-11 2018-02-16 瑞士优北罗股份有限公司 The method of modem apparatus, communication system and processing cycle prefix
CN107733536A (en) * 2016-08-11 2018-02-23 中国电信股份有限公司 Antenna calibration method and system, calibration signal processor
CN109818706A (en) * 2018-12-04 2019-05-28 维沃移动通信有限公司 A kind of signal processing method and device
CN111641487A (en) * 2020-06-03 2020-09-08 江苏亨通太赫兹技术有限公司 Multi-channel high-frequency wireless data transmission method and system based on link aggregation
CN113507296A (en) * 2021-09-13 2021-10-15 北京思凌科半导体技术有限公司 Communication method, communication apparatus, storage medium, and electronic device
CN114189286A (en) * 2021-10-28 2022-03-15 华中科技大学 Method and system for simultaneously calibrating frequency response and IQ time delay difference of coherent optical transceiver
CN115412207A (en) * 2022-08-29 2022-11-29 上海金卓科技有限公司 Coding method and device and decoding method and device of space-time-frequency block code

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102185819A (en) * 2011-05-09 2011-09-14 中国科学院上海微系统与信息技术研究所 OFDM (Orthogonal Frequency Division Multiplexing) time synchronization algorithm based on conjugate symmetric sequence
EP3352397B1 (en) * 2015-09-17 2021-10-27 Sony Group Corporation Device and method
CN110890912A (en) * 2019-06-04 2020-03-17 熊军 Beam forming method with decision feedback frequency domain equalization under multiple antennas
CN115442198B (en) * 2022-08-30 2024-04-12 哈尔滨工业大学 Non-cellular communication radar integrated receiving and transmitting method based on vector orthogonal frequency division multiplexing
CN115913841B (en) * 2022-11-25 2024-06-04 中北大学 Data equalization method for equivalent time sampling signal

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100849984B1 (en) * 2002-05-28 2008-08-01 삼성전자주식회사 Time Domain Synchronous-Orthogonal Frequency Division Multiplexing transmitter and a method processing OFDM signal thereof
US7177297B2 (en) * 2003-05-12 2007-02-13 Qualcomm Incorporated Fast frequency hopping with a code division multiplexed pilot in an OFDMA system
CN1617530A (en) * 2004-12-06 2005-05-18 山东大学 Frequency selective mode single carrier blocking transmission method

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101534278B (en) * 2009-04-10 2011-08-17 北京大学 Time-frequency expansion Orthogonal Frequency Division Multiplexing transmitting and receiving device, method and system
CN103973611A (en) * 2013-01-25 2014-08-06 普天信息技术研究院有限公司 Frequency deviation correction method
CN103973611B (en) * 2013-01-25 2017-05-31 普天信息技术研究院有限公司 A kind of frequency deviation correcting method
CN103325232B (en) * 2013-07-08 2020-02-07 北京新岸线移动多媒体技术有限公司 Terminal control implementation method, system and terminal equipment
CN103325232A (en) * 2013-07-08 2013-09-25 北京新岸线移动多媒体技术有限公司 Terminal control realization method and system and terminal equipment
CN107710708B (en) * 2015-06-11 2021-05-07 瑞士优北罗股份有限公司 Modem device, communication system, and method of processing cyclic prefix
CN107710708A (en) * 2015-06-11 2018-02-16 瑞士优北罗股份有限公司 The method of modem apparatus, communication system and processing cycle prefix
WO2017071574A1 (en) * 2015-10-30 2017-05-04 华为技术有限公司 Method and device for sending data
CN107733536B (en) * 2016-08-11 2021-04-20 中国电信股份有限公司 Antenna calibration method and system, and calibration signal processor
CN107733536A (en) * 2016-08-11 2018-02-23 中国电信股份有限公司 Antenna calibration method and system, calibration signal processor
CN106597384A (en) * 2016-12-21 2017-04-26 中国航空工业集团公司雷华电子技术研究所 OFDM (Orthogonal Frequency Division Multiplexing) modulation based constant envelope waveform generation circuit
CN106597384B (en) * 2016-12-21 2019-02-12 中国航空工业集团公司雷华电子技术研究所 A kind of weighing apparatus envelope waveform generation circuit based on OFDM modulation
CN107171999A (en) * 2017-06-13 2017-09-15 电子科技大学 A kind of method for ofdm system feature suppression
CN107171999B (en) * 2017-06-13 2019-08-02 电子科技大学 A method of for ofdm system feature suppression
CN109818706B (en) * 2018-12-04 2020-09-29 维沃移动通信有限公司 Signal processing method and device
CN109818706A (en) * 2018-12-04 2019-05-28 维沃移动通信有限公司 A kind of signal processing method and device
CN111641487A (en) * 2020-06-03 2020-09-08 江苏亨通太赫兹技术有限公司 Multi-channel high-frequency wireless data transmission method and system based on link aggregation
CN113507296A (en) * 2021-09-13 2021-10-15 北京思凌科半导体技术有限公司 Communication method, communication apparatus, storage medium, and electronic device
CN113507296B (en) * 2021-09-13 2022-01-11 北京思凌科半导体技术有限公司 Communication method, communication apparatus, storage medium, and electronic device
CN114189286A (en) * 2021-10-28 2022-03-15 华中科技大学 Method and system for simultaneously calibrating frequency response and IQ time delay difference of coherent optical transceiver
CN114189286B (en) * 2021-10-28 2023-02-14 华中科技大学 Method and system for simultaneously calibrating frequency response and IQ time delay difference of coherent optical transceiver
CN115412207A (en) * 2022-08-29 2022-11-29 上海金卓科技有限公司 Coding method and device and decoding method and device of space-time-frequency block code
CN115412207B (en) * 2022-08-29 2024-02-23 上海金卓科技有限公司 Encoding method and device and decoding method and device for space-time-frequency block code

Also Published As

Publication number Publication date
WO2006125343A1 (en) 2006-11-30

Similar Documents

Publication Publication Date Title
CN101204030A (en) Quadrature frequency-division and time-division transmitter, receiver and method thereof
EP1679849B1 (en) OFDM communication apparatus and method, wherein the pilot symbols are weighted in order to reduce the peak to average power ratio
JP5571131B2 (en) Code division multiplexing in a single carrier frequency division multiple access system.
CN101421943B (en) Mimo receiving apparatus
CN101355541B (en) Blocking equalizing method for OFDM system under Quick-Change channel condition
KR100873173B1 (en) System and Method for co-channel interference cancellation in cellular OFDM systems
WO2005086446A1 (en) Ofdm transceiver structure with time-domain scrambling
WO2006071056A1 (en) Method and apparatus for transmitting/receiving a signal in an ffh-ofdm communication system
JP2005304040A (en) Transmitter-receiver apparatus for fast frequency hopping in orthogonal frequency division multiple connection system
JP5486734B2 (en) Transmission signal generating apparatus and method in single carrier communication system
US20080225689A1 (en) Orthogonal frequency division multiplexing having tones with overlaid data and pilot symbols
CN108847917B (en) Orthogonal frequency division multiplexing transmission method modulated by pilot frequency pattern
CN1885844B (en) Device for reducing peak-to-average ratio based on orthogonal multiplex multi-carrier transmission and its method
CN109302240A (en) The serial equalization methods of low complex degree OSDM based on double selection fading channels
CN101232481B (en) Signal channel estimating method and corresponding sending and receiving device
JP2004507972A (en) Partial response signaling for orthogonal frequency division multiplexing
KR101042774B1 (en) Method and apparatus for transmitting/receiving a signal in a fast frequency hopping - orthogonal frequency division multiplexing communication system
CN103166879A (en) Channel estimation method and orthogonal frequency division multiplexing (OFDM) system using same
CN105991489A (en) Method for realizing channel equalization by using frequency-domain oversampling
CN100536449C (en) Signal transmitting method and apparatus based on cyclic prefix
KR20060072096A (en) Apparatus and method for calculation of llr in a orthogonal frequency division multiplexing communication system using linear equalizer
CN101719816A (en) Method for realizing low feedback velocity of self-adaptive MIMO-SCFDE system
KR100781044B1 (en) The aparatus and method for Channel Estimation For Wirelss Telecommnunication System
Simon A Performance Analysis of Wavelet based LTE-OFDM with Multi-equalizers
Charrada et al. SIMO-OFDM Channel Estimation based on Nonlinear Complex LS-SVM

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C02 Deemed withdrawal of patent application after publication (patent law 2001)
WD01 Invention patent application deemed withdrawn after publication

Open date: 20080618