CN1885846A - Orthogonal frequency-division multiplexing system and selective mapping transmitting and receiving method - Google Patents
Orthogonal frequency-division multiplexing system and selective mapping transmitting and receiving method Download PDFInfo
- Publication number
- CN1885846A CN1885846A CN 200610081461 CN200610081461A CN1885846A CN 1885846 A CN1885846 A CN 1885846A CN 200610081461 CN200610081461 CN 200610081461 CN 200610081461 A CN200610081461 A CN 200610081461A CN 1885846 A CN1885846 A CN 1885846A
- Authority
- CN
- China
- Prior art keywords
- sequence
- supplementary
- data
- phase
- stream
- 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
Links
Images
Landscapes
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
The invention provides an OFDM system and selective mapping transmission and receiving method, wherein it uses N-point correlator assisted search information to enhance system anti-noise capacity, conjugate multiplies and sums to let frequency attenuation only affect part sequence value of the correlator, and can decide the phase deflection value correctly. This invention makes proper use of IFFT point number to improve system performance, such as reducing PAPR.
Description
Technical field
The present invention relates to OFDM (OFDM) communication system, more particularly, relate to and a kind ofly be used for orthogonal FDM communication system selectivity mapping (SLM) and transmit and receive data to reduce the method for ofdm system peak-to-average power ratio (PAPR).
Background technology
In current various transmission technologys, the OFDM technology receives suitable concern, because it is to utilize parallel transmission data on the very little subcarrier in the interval with overlapping frequency spectrum, thereby has improved spectrum efficiency greatly, has significantly increased message transmission rate.In the OFDM technology, modulate by IFFT (invert fast fourier transformation), and carry out demodulation by FFT (fast fourier transform).
Below the operation of the transmitter and receiver in the OFDM wireless communication system will be described simply.
The OFDM transmitter at scrambler, encode and interweave after, modulating input data on subcarrier, and variable data rate is provided.Determine encoding rate, interleaver sizes and modulation scheme according to this data transfer rate.In general, use 1/2 or 3/4 encoding rate, and interleaver sizes depends on the number of the coded bit of every OFDM code element.About modulation, data transfer rate as required and adopt QPSK (quadriphase keying), 8PSK (eight phase keying), 16QAM (16 quadrature amplitude modulation) or 64QAM (64 quadrature amplitude modulation).The pilot tone of predetermined number is added on another predetermined number subcarrier.Then, the IFFT piece is imported as it with these subcarriers and pilot tone, and produces ofdm signal.Protection is inserted in the ofdm signal at interval to eliminate the inter symbol interference (ISI) in the multi-path channel environment.Thereafter, the OFDM waveform produces in the signal waveform generator, and finally sends from RF (radio frequency) module on radio channel.
Except appended synchronization, the OFDM receiver is carried out demodulation with the order opposite with the transmitter operation.At first, utilize predetermined skew of training symbol estimated frequency and symbol offset.To have been eliminated by FFT then protects data symbols at interval to revert to the subcarrier of the predetermined number of the pilot tone that comprises predetermined number.Equalizer is estimated channel condition, and removes the distorted signals that channel causes from received signal, postpones to prevent multipath.The data that compensated channel response in equalizer are converted into bit stream, and are deinterleaved.After decoding and descrambling, data revert to initial data.
Replacement sends data with two-forty on single carrier wave, in the OFDM technology, OFDM is divided into parallel data stream with data, and sends them so that low rate is parallel on a plurality of carrier waves.Thus, OFDM makes the significant digits of modulator/demodulator realize becoming possibility, and frequency selective fading or narrow band interference are had robustness.Because these advantages, the high speed data transfer technology that the OFDM technology adopts as current European digital broadcasting service standard and IEEE 802.11a and IEEE 802.16 standards.
Consider the transfer of data on a plurality of carrier waves, represent the amplitude of ofdm signal with the amplitude sum of a plurality of carrier waves.If these carrier waves are homophase each other, then ofdm signal has very high peak-to-average force ratio (PAPR), such ofdm signal has reduced the efficient of the linear amplifier of high power, and at nonlinear area operation high power amplifier, thereby between carrier wave, introduced intermodulation distortion and spectral re-growth.Therefore, the PAPR of ofdm system has been reduced and carried out many researchs.
PAPR reduction method comprises amplitude limit (clipping), block encoding and phase place adjustment.Amplitude limit is the scheme that the peak swing of input signal is restricted to the peak swing of expectation.It is easy to reduce PAPR, yet because nonlinear operation, amplitude limit causes inband distortion, has increased BER (error rate), and has introduced the outer clipped noise of band, so, produce adjacent-channel interference.
To extra carrier execution block coding, to reduce the PAPR of whole carrier wave.This scheme is not having to have realized under the situation of distorted signals that error correction and PAPR reduce.Yet, if subcarrier band is roomy, the non-constant of spectrum efficiency, and the size of look-up table or generator matrix becomes too big.As a result, block encoding is very complicated, and needs a large amount of calculating.
At last, utilize selectivity mapping (SLM) scheme or the adjustment of part transmission sequence (PTS) excute phase.PTS is the flexible solution that does not have the reduction PAPR of nonlinear distortion.The input data are divided into M sub-piece.And after L point (L-point) IFFT, each sub-piece is multiplied by and makes the minimized phase factor of PAPR.Before sending with these product additions.Although there is advantage, PTS need with the as many IFFT of sub-piece number M, and, calculate the needed amount of calculation of phase factor and become huge along with the increase of sub-piece number.Therefore, the high speed information transmission is suppressed.
Replacedly, the SLM scheme multiply by the out of phase sequence that length is N with M identical block, and selects to have the product of minimum PAPR, so that send.This scheme needs M IFFT computing, but advantageously, has significantly reduced PAPR, and do not limited carrier number.
Fig. 1 is the block diagram of the SLM transmitter in traditional ofdm system.As shown in Figure 1, SLM transmitter 100 by mapping table 110, the string also (S/P) transducer 120, distributor 130, phase sequence generator 140, a plurality of multiplier 150 to 154, a plurality of IFFT160 to 164 and selector 170 are formed.
With reference to figure 1, encoding with the predictive encoding rate, and after interweaving, the information that send is applied to mapping table 110, mapping table 110 will be imported data map to modulated symbol according to preset modulation scheme.S/P transducer 120 will be converted to L paralleled code element from the continuous code element that mapping table 110 receives according to the number (L point) of the input tap of IFFT 160 to 164.Distributor 130 copies as U data block for U IFFT 160 to 164 with these paralleled code elements, and these data blocks are mail to multiplier 150 to 154.
The phase sequence that it is N that phase sequence generator 140 will be added up independently U length offers multiplier 150 to 154.Use these phase sequences to adjust the phase place of input data.Multiplier 150 to 154 multiply by the out of phase sequence that receives from phase sequence generator 140 for the data that receive from distributor 130.
IFFT is carried out in the output of 160 to 164 pairs of multipliers 150 to 154 of IFFT, and selector 170 selects to have the IFFT output of minimum PAPR from the output of IFFT 160 to 164.
As shown in Figure 1, although SLM needs U IFFT operation, it advantageously reduces PAPR, and irrespectively applicable with carrier number.And compare with PTS, amount of calculation is little and computing time is not long.So SLM helps the high speed information transmission.
Yet the special shortcoming of SLM is receiver and must knows selected phase sequence, so that receive the function restore data.Thus, need effectively send phase sequence selects information to realize the method for SLM in ofdm system.
At application number is in the patent of invention of 03816132.X, and this invention provides a kind of SLM method to send the equipment and the method for supplementary, and the block diagram of its patent of invention SLM transmitter and receiver as shown in Figures 2 and 3.The SLM transmitter is by mapping table 210, S/P transducer 220, distributor 230, phase sequence and supplementary generator 240, a plurality of multiplier 250 to 254, a plurality of supplementary inserter 260 to 264, a plurality of IFFT270 to 274, and selector 280 is formed.
The input data are being encoded with the predictive encoding rate, and after interweaving, the input data are applied to mapping table 210.Although available many modes are encoded to data, prevailing type of coding is the turbo coding that is used for error correction.Encoding rate can be 1/2 or 3/4.
Mapping table 210 will be imported data map to modulated symbol according to preset modulation scheme.S/P transducer 220 will be converted to paralleled code element from the order code element that mapping table 210 receives.Distributor 230 copies as U data block for each IFFT of U 260 to 264 with these paralleled code elements, and these data blocks are mail to multiplier 250 to 254.Each data block comprises a plurality of code elements and is exported simultaneously concurrently.
It is that the phase sequence of N offers multiplier 250 to 254 that phase sequence and supplementary generator 240 are added up length independently with U, and the identifier (ID) that will identify phase sequence is provided to supplementary inserter 260 to 264 as supplementary.Use these phase sequences to adjust the phase place of input data, and phase sequence ID is that length is log
2The index type of U bit.
Multiplier 250 to 254 multiply by from the out of phase sequence of phase sequence and 240 receptions of supplementary generator for the data that receive from distributor 230, thereby rotates the phase place of these data blocks.Supplementary inserter 260 to 264 inserts phase sequence ID to U data block front or the back through the phase place rotation.In other words, supplementary provides the information about the phase place rotation.IFFT is carried out in the output of IFFT270 to 274 pair of supplementary inserter 260 to 264.Final selector 280 calculates the PAPR of the data block of passing through invert fast fourier transformations, and selects a data block of passing through invert fast fourier transformation with minimum PAPR as ofdm signal.
For the receiver of this algorithm, the SLM receiver is by S/P transducer, FFT, parallel-to-serial converter, multiplier, supplementary monitor, phase sequence generator, side information remover, and removes compositions such as mapping table.
RF signal on a plurality of carrier waves is converted into digital baseband signal, and is being used for synchronously and after the predetermined process of noise removing, is being applied to the S/P transducer as input signal.The S/P transducer is that benchmark is converted to L parallel signal with input signal with the code element according to the input number of taps (L point) of FFT.FFT carries out FFT to paralleled code element.The P/S transducer FFT code element that will walk abreast is converted to the serial data block that length is L, and it is outputed to multiplier and side information detector.
Side information detector is from the precalculated position, i.e. the beginning of data block or ending detects supplementary.This supplementary is log
2The index of U bit, expression are used for the phase sequence of the phase place rotation of data block.This phase sequence generator produces the inverted value of the phase sequence corresponding with this index.
Multiplier is given the phase sequence after the data block that receives multiply by negate.Side information remover is removed supplementary from the output of multiplier.Go mapping table mapping to be gone in the output of side information remover, thereby recover initial data according to predetermined modulation schemes.
Simultaneously, side information remover can be in the front end operation of multiplier.That is to say, from data block, remove supplementary, multiply by the phase sequence after the negate subsequently.
By the analysis to this patent, we might as well find that this method exists following defective:
(1) wastes certain resource and be used for transmitting supplementary, caused the decline of system transmissions efficient.And along with the increase of transmitter phase auxiliary sequencel range of choice, its wasting of resources is just remarkable more, and system transmissions efficient reduces greatly.
(2) transmission by channel, interference of noise, the transmission of supplementary exists the error effect identical with data message, and the acquisition of supplementary is not by special coding and interference protection measure, that causes supplementary correctly obtains the error that exists quite big probability, thereby badly influence the correct judgement of auxiliary phase sequence, cause the serious decline of systematic function.
Summary of the invention
The object of the invention is to provide a kind of ofdm system and selectivity mapping method of sending and receiving.
Selectivity mapping sending method provided by the present invention comprises: enter the constellation mapping table through the data after coding, the interleaving treatment and shine upon back output sequence of complex numbers; This sequence of complex numbers flows to into deserializer, and data flow becomes corresponding parallel data stream by serial converted; Parallel data stream enters distributor then, and parallel data stream is copied into the U road; U channel parallel data flow point U road phase place other and that the phase sequence generator is produced multiplies each other, thereby finishes the phase place deflection of data flow; When the phase sequence generator produces random phase, according to the supplementary of relation generation one to one plural number stream, carry out plural addition summation through the data flow of phase place deflection and corresponding supplementary plural number stream according to the certain power proportionate relationship, produce the parallel data that the U road comprises phase place deflection and supplemental stream; The U channel parallel data carries out the IFFT conversion that N is ordered respectively, the time-domain signal sequence after the output U road conversion; Selector selects the minimum data flow of peak-to-average power ratio to transmit from the output signal sequence of U road.
Selectivity mapping method of reseptance provided by the present invention comprises step: the input data after the handling processes such as the signal process analog to digital conversion that at first receives, removal Cyclic Prefix, same step calibration, frequency offset correction enter deserializer, and serial data is become parallel data; The sequence of complex numbers stream of output frequency domain after the parallel data process N point FFT conversion; Parallel data becomes the serial complex data flow through parallel-to-serial converter again, the supplemental stream that serial data stream and supplementary generator produce enters correlator, and to carry out conjugation relevant, by comparing the peak value after the known transmission supplementary plural number of U kind flows to line correlation, can learn the supplementary sequence of complex numbers value of reflector selection transmission; The serial data stream that receives after the FFT conversion is deducted supplementary sequence of complex numbers value, can obtain through the later initial data of phase place deflection; Because the phase sequence of side information data stream and phase generator has relation one to one, affirmation by supplementary sequence of complex numbers value, just get the selected random phase sequence of cicada reflector tilt value simultaneously, the phase sequence generator produces a negative-phase sequence train value with the phase sequence of reflector selection, multiply by the reception data of above-mentioned correspondence, just can obtain not add the initial data of phase place deflection; Initial data is gone mapping through constellation, just can obtain data bit flow.
Transmitter provided by the present invention comprises mapping table, and it will be encoded through the predictive encoding rate according to preset modulation scheme, and the input data bit that interweaves later is mapped to modulated symbol; The S/P transducer, it will convert corresponding parallel data stream from the serial data stream that mapping table receives to; Distributor is copied into U data block with parallel data; Phase sequence and supplementary generator produce U and add up independently phase sequence, and the length of each phase sequence is N, produces U auxiliary plural information that length is N one to one according to phase sequence simultaneously; Multiplier, it is used for U data block that distributor is come out and adds up independently with U that phase sequence multiplies each other respectively; Adder adds the supplementary sequence corresponding with this phase sequence respectively with U the data sequence after out of phase deflection, obtains U different data sequence stream; The IFFT converter is used for U data block carried out invert fast fourier transformation then respectively, obtains U time-domain signal data block.
Receiver provided by the present invention comprises: serial-parallel converter, the carrying out that receiver is received digital to analog conversion, sign synchronization regularly and the serial data stream of the signal behind frequency offset processing and the removal Cyclic Prefix be transformed into parallel data block; The FFT converter carries out the FFT conversion and exports the frequency domain parallel data block above-mentioned parallel data block; Parallel to serial converter is used for the parallel data block of input is transformed to serial data stream; The supplementary generator is used to produce the U kind supplementary sequence identical with transmitter; Correlator, be used for received signal and this U kind supplementary sequence are carried out respectively relevant, by the output energy peak of correlator relatively, the selected definite supplementary sequence of output transmitter; The output that subtracter, the signal that is used for receiving deduct above-mentioned correlator obtains the phase sequence after the phase place deflection; The phase sequence generator, the supplementary by correlator output obtains the phase place deflection that ofdm system SLM transmitter carries out initial data; Multiplier is used for the opposite phase sequence of phase sequence after the phase place deflection of subtracter output and the output of phase sequence generator is multiplied each other so that obtain initial data; Remove mapping table, be used for the initial data of multiplier output is carried out inverse mapping, deinterleaving and decoding.
By method of the present invention and transmitter and receiver, we can obtain following significant advantage: SLM of the present invention assists the process that transmits and receives of side information, does not need the resource of the system of wasting, and has improved the efficiency of transmission of system greatly.The present invention has utilized the N point correlators to carry out seeking and visiting of supplementary, has strengthened the ability of system's opposing channel and random noise disturbance.We know that in frequency selective fading channels some frequency may be interfered, and distorts.Yet the correlator by N point length carries out suing for peace after the conjugate multiplication, the just partial order train value of correlator that the influence of fading of component frequency arrives, still exist a large amount of sequential values with strong correlation, the peak value that is to say correlator output is affected slightly, and can not have influence on the judgement that supplementary is sent sequence, thereby the correct phase place tilt value of judging correspondence.The increase that method of the present invention is counted along with IFFT can not make whole system reduce the decreased performance of PAPR.On the contrary, the increase of counting along with IFFT, the length of supplementary sequence of complex numbers value increases, the length of correlator increases, make that the output peak value of correlator is more sharp-pointed, thereby strengthened system greatly to anti-jamming capacity, improved the ability of correct reception and judgement supplementary, thereby increased the performance of system.
Description of drawings
Fig. 1 is the block diagram of the SLM transmitter in traditional ofdm system;
Fig. 2 is the block diagram of traditional SLM transmitter;
Fig. 3 is the block diagram of traditional SLM receiver;
Fig. 4 is the block diagram according to the SLM transmitter of ofdm system of the present invention;
Fig. 5 is the block diagram according to ofdm system SLM receiver of the present invention;
Fig. 6 is a correlator energy output analogous diagram.
Embodiment
The present invention is by the analysis to the patent (its number of patent application is 03816132.X) announced, design a kind of effective method more that overcomes this patent defective, be used for transmitting SLM transmitter supplementary, not only improved system transmissions efficient greatly, and strengthened system's anti-jamming capacity, thereby improved the performance of ofdm system.
SLM transmitter block diagram of the present invention such as Fig. 4, receiver block diagram as shown in Figure 5, its data flow and algorithm principle are as follows:
Enter the constellation mapping table through the data after coding, the interleaving treatment and shine upon back output sequence of complex numbers; This sequence of complex numbers flows to into deserializer, and data flow becomes corresponding parallel data stream by serial converted; Parallel data stream enters distributor then, and parallel data stream is copied into the U road; U channel parallel data flow point U road phase place other and that the phase sequence generator is produced multiplies each other, thereby finishes the phase place deflection of data flow.In the design process, the producing method of U road phase place is randomized process, and the U road phase place after the generation is determined respectively and preserved at transmitter and receiver, to make things convenient for demodulation; When the phase sequence generator produces random phase, according to the supplementary of relation generation one to one plural number stream, the length of the supplementary plural number stream of corresponding each road phase value is IFFT transform length N, satisfies the relation (summing value that the plural number on the corresponding position carries out after the conjugate multiplication is 0) of conjugation quadrature between each road supplementary plural number stream; Carry out plural addition summation through the data flow of phase place deflection and corresponding supplementary plural number stream according to the certain power proportionate relationship, produce the parallel data that the U road comprises phase place deflection and supplemental stream; The U channel parallel data carries out the IFFT conversion that N is ordered respectively, the time-domain signal sequence after the output U road conversion; Selector selects the minimum data flow of PAPR to transmit from the output signal sequence of U road.
The flow chart of data processing of SLM receiver is: the signal that at first receives enters deserializer through analog to digital conversion, the input data removed after the handling processes such as Cyclic Prefix, same step calibration, frequency offset correction, and serial data is become parallel data flow chart of data processing such as (also may carry out) synchronously, frequency deviations after the FFT conversion; The sequence of complex numbers stream of output frequency domain after the parallel data process N point FFT conversion; Parallel data becomes the serial complex data flow through parallel-to-serial converter again, and by the flow chart of data processing of SLM transmitter, we know that this complex data flow has comprised the raw value of auxiliary sequence of complex numbers value and the deflection of process phase place; The supplemental stream that serial data stream and supplementary generator produce enters correlator (length of correlator is N), and to carry out conjugation relevant, flow to peak value behind the line correlation by the known transmission supplementary plural number of U kind relatively, thereby can learn that reflector selects the supplementary sequence of complex numbers value of transmission; The serial data stream that receives after the FFT conversion is deducted supplementary sequence of complex numbers value, just can obtain through the later initial data of phase place deflection; Because the phase sequence of side information data stream and phase generator has relation one to one, affirmation by supplementary sequence of complex numbers value, just get the selected random phase sequence tilt value of cicada reflector simultaneously, the phase sequence generator produces a negative-phase sequence train value with the phase sequence of reflector selection, multiply by corresponding reception data, so just can obtain not add the initial data of phase place deflection; Initial data is gone mapping through constellation, just can obtain data bit flow, thereby continue to finish the following continuous handling process that receives data.
Below in conjunction with the invention block diagram, specific implementation process of the present invention is elaborated.
In ofdm system, encoding with the predictive encoding rate, and after interweaving, the input data bit enters mapping table, mapping table will be imported data map to modulated symbol (mapping is output as the sequence of complex numbers stream of order in the WiMAX system) according to preset modulation scheme, and the S/P transducer will convert corresponding parallel data stream from the serial data stream that mapping table receives to.Distributor is copied into U data block with parallel data, and each data block comprises N data symbol (X=X
1, X
2X
N).
Phase sequence and supplementary generator produce U and add up independently phase sequence P
1, P
2... P
U, the length of each phase sequence is N (p
1, p
2... P
N), produce U auxiliary plural information A that length is N one to one according to phase sequence simultaneously
1, A
2... A
U, require between the supplementary sequence that U length is N to satisfy mutually orthogonal, promptly
Then, the U that distributor a comes out data block adds up independently with U that phase sequence multiplies each other respectively, produces the data sequence of U out of phase deflection
U the data sequence after out of phase deflection adds the supplementary sequence corresponding with this phase sequence respectively, obtains U different data sequence stream
In order effectively to utilize transmitting power, increase system's area coverage, supplementary power and data power can be carried out addition synthetic (suggestion of x value is 1～1/5) according to certain ratio value x, thereby improve system's ERP.
U data block carried out the IFFT conversion then respectively, obtains U time-domain signal data block x
1 i, x
2 i... x
N i, i=1,2 ... N.Selector calculates respectively the time-domain data blocks of this U output, selects relatively wherein that peak-to-average force ratio PAPR minimal data piece amplifies, and sends after being modulated to radio frequency.
For the ofdm system SLM receiver of this method, its Data Receiving handling process is:
Receiver carries out digital to analog conversion with the signal that receives, sign synchronization timing and frequency offset processing (are noted, in the actual ofdm system of design, handling processes such as sign synchronization timing and frequency offset correction also can be carried out after the FFT conversion), remove the later serial data stream of Cyclic Prefix and enter serial-parallel converter, serial data is transformed into parallel data block, carry out the FFT conversion then, output frequency domain parallel data block, parallel data block enters parallel to serial converter, obtains serial data stream.By the flow chart of data processing of SLM transmitter, we know that this data flow is the original data stream that comprised phase place deflection and the supplementary received signal behind the interchannel noise that superposeed.
The supplementary generator produces the U kind supplementary sequence identical with transmitter, received signal and this U kind supplementary sequence is carried out relevant respectively, and the output energy peak by the comparison correlator can find the selected definite supplementary sequence of transmitter.Owing to comprised certain supplementary sequential value in the received signal, thus the supplementary sequence that and if only if enters correlator with the supplementary sequence in the received signal identical the time, the energy that correlator is exported is obtained peak-peak; Enter the supplementary sequence of correlator for other and since with received signal in the complete quadrature of supplementary sequence that comprises, its correlator output energy shows as random noise, it is worth well below energy peak.For be superimposed upon in the signal noise with the initial data of phase place deflection has taken place, its correlation with the supplementary sequence is very poor, its relevant energy of exporting still shows as noise energy, it is worth well below the correlator energy peak.Fig. 6 is that the transmission data that comprised certain supplementary have superposeed after signal to noise ratio is the white gaussian channel noise of 20dB, with the emulation energy diagram (the N value is 512) that 200 completely orthogonal supplementarys are carried out the output of relevant back, we can correctly obtain the selected supplementary sequence of ofdm system SLM transmitter from this analogous diagram.
Because exist relation one to one between certain supplementary and certain phase sequence, by the acquisition of supplementary, we can obtain the phase place deflection that ofdm system SLM transmitter carries out initial data.To deduct supplementary by the received data of P/S transducer, opposite phase sequence with the generation of phase sequence generator multiplies each other then, just obtained initial data, data have been carried out processes such as inverse mapping, deinterleaving and decoding, we have just recovered original data bits.
Claims (8)
1, a kind of method that is used for the orthogonal FDM communication system transmission about the supplementary of selectivity mapping is characterized in that may further comprise the steps:
(1) enters the constellation mapping table through the data after coding, the interleaving treatment and shine upon back output sequence of complex numbers;
(2) this sequence of complex numbers flows to into deserializer, and data flow becomes corresponding parallel data stream by serial converted;
(3) parallel data stream enters distributor then, and parallel data stream is copied into the U road;
(4) U channel parallel data flow point U road phase place other and that the phase sequence generator is produced multiplies each other, thereby finishes the phase place deflection of data flow;
When (5) the phase sequence generator produces random phase, according to the supplementary of relation generation one to one plural number stream, carry out plural addition summation through the data flow of phase place deflection and corresponding supplementary plural number stream according to the certain power proportionate relationship, produce the parallel data that the U road comprises phase place deflection and supplemental stream;
(6) the U channel parallel data carries out the IFFT conversion that N is ordered respectively, the time-domain signal sequence after the output U road conversion;
(7) selector selects the minimum data flow of peak-to-average power ratio to transmit from the output signal sequence of U road.
2. method according to claim 1 is characterized in that: the producing method of U road phase place is randomized process, and the U road phase place after the generation is determined respectively and preserved at transmitter and receiver, to make things convenient for demodulation.
3. method according to claim 1 and 2 is characterized in that: the length of the supplementary plural number stream of corresponding each road phase value is IFFT transform length N, satisfies the relation of conjugation quadrature between each road supplementary plural number stream.
4. one kind is used for the method that orthogonal FDM communication system receives the supplementary of shining upon about selectivity, it is characterized in that may further comprise the steps:
Input data after the handling processes such as the signal process analog to digital conversion that (a) at first receives, removal Cyclic Prefix, same step calibration, frequency offset correction enter deserializer, and serial data is become parallel data;
(b) the sequence of complex numbers stream of output frequency domain after the parallel data process N point FFT conversion;
(c) parallel data becomes the serial complex data flow through parallel-to-serial converter again, the supplemental stream that serial data stream and supplementary generator produce enters correlator, and to carry out conjugation relevant, by comparing the peak value after the known transmission supplementary plural number of U kind flows to line correlation, can learn the supplementary sequence of complex numbers value of reflector selection transmission;
(d) serial data stream that receives after the FFT conversion is deducted supplementary sequence of complex numbers value, can obtain through the later initial data of phase place deflection;
(e) because the phase sequence of side information data stream and phase generator has relation one to one, affirmation by supplementary sequence of complex numbers value, just get the selected random phase sequence of cicada reflector tilt value simultaneously, the phase sequence generator produces a negative-phase sequence train value with the phase sequence of reflector selection, multiply by the reception data of above-mentioned correspondence, just can obtain not add the initial data of phase place deflection;
(f) initial data is gone mapping through constellation, just can obtain data bit flow.
5. an orthogonal FDM communication system comprises selectivity mapping SLM transmitter and receiver, it is characterized in that:
Described transmitter comprises
Mapping table, it will be encoded through the predictive encoding rate according to preset modulation scheme, and the input data bit that interweaves later is mapped to modulated symbol;
The S/P transducer, it will convert corresponding parallel data stream from the serial data stream that mapping table receives to;
Distributor is copied into U data block with parallel data;
Phase sequence and supplementary generator produce U and add up independently phase sequence, and the length of each phase sequence is N, produces U auxiliary plural information that length is N one to one according to phase sequence simultaneously;
Multiplier, it is used for U data block that distributor is come out and adds up independently with U that phase sequence multiplies each other respectively;
Adder adds the supplementary sequence corresponding with this phase sequence respectively with U the data sequence after out of phase deflection, obtains U different data sequence stream;
The IFFT converter is used for U data block carried out invert fast fourier transformation then respectively, obtains U time-domain signal data block;
Above-mentioned receiver comprises:
Serial-parallel converter, the carrying out that receiver is received digital to analog conversion, sign synchronization regularly and the serial data stream of the signal behind frequency offset processing and the removal Cyclic Prefix be transformed into parallel data block;
The FFT converter carries out the FFT conversion and exports the frequency domain parallel data block above-mentioned parallel data block;
Parallel to serial converter is used for the parallel data block of input is transformed to serial data stream;
The supplementary generator is used to produce the U kind supplementary sequence identical with transmitter;
Correlator, be used for received signal and this U kind supplementary sequence are carried out respectively relevant, by the output energy peak of correlator relatively, the selected definite supplementary sequence of output transmitter;
The output that subtracter, the signal that is used for receiving deduct above-mentioned correlator obtains the phase sequence after the phase place deflection;
The phase sequence generator, the supplementary by correlator output obtains the phase place deflection that ofdm system SLM transmitter carries out initial data;
Multiplier is used for the opposite phase sequence of phase sequence after the phase place deflection of subtracter output and the output of phase sequence generator is multiplied each other so that obtain initial data;
Remove mapping table, be used for the initial data of multiplier output is carried out inverse mapping, deinterleaving and decoding.
6. system according to claim 5 is characterized in that: it is synthetic supplementary power and data power can be carried out addition according to certain ratio value, and the scope of this value is 1～1/5.
7. according to claim 5 or 6 described systems, it is characterized in that: in correlator, when the supplementary sequence in supplementary sequence that enters correlator and the received signal was identical, the energy of correlator output was obtained peak-peak; Enter the supplementary sequence of correlator for other, because with the complete quadrature of supplementary sequence that comprises in the received signal, its correlator output energy shows as random noise, and it is worth well below energy peak, therefore obtains the selected definite supplementary sequence of transmitter.
8. system according to claim 5, the supplementary sequence that the supplementary generator in the phase sequence in the wherein said transmitter and supplementary generator and the receiver produces all is mutually orthogonal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610081461 CN1885846A (en) | 2006-05-22 | 2006-05-22 | Orthogonal frequency-division multiplexing system and selective mapping transmitting and receiving method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610081461 CN1885846A (en) | 2006-05-22 | 2006-05-22 | Orthogonal frequency-division multiplexing system and selective mapping transmitting and receiving method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1885846A true CN1885846A (en) | 2006-12-27 |
Family
ID=37583825
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200610081461 Pending CN1885846A (en) | 2006-05-22 | 2006-05-22 | Orthogonal frequency-division multiplexing system and selective mapping transmitting and receiving method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1885846A (en) |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101848184A (en) * | 2010-06-03 | 2010-09-29 | 山东大学 | Selective mapping scrambling method for reducing peak-to-average power ratio of orthogonal frequency division multiplexing system |
| CN101478520B (en) * | 2008-12-15 | 2011-08-03 | 北京创毅视讯科技有限公司 | Descramble method and apparatus |
| CN101431505B (en) * | 2008-12-03 | 2011-08-31 | 山东大学 | Emission system and method for reducing peak-to-average power ratio of orthogonal frequency division multiplexing system |
| CN102263765A (en) * | 2011-08-22 | 2011-11-30 | 宁波大学 | Robust transmission method of digital broadcast mobile signals |
| CN102263761A (en) * | 2011-08-22 | 2011-11-30 | 宁波大学 | Method for modulating framing of multimedia wireless broadcast signals |
| CN102271117A (en) * | 2011-08-22 | 2011-12-07 | 宁波大学 | Anti-interference multimedia wireless broadcast signal framing modulation method |
| CN102273158A (en) * | 2008-12-31 | 2011-12-07 | 高通股份有限公司 | Methods and systems for papr reduction in sc-fdma systems |
| CN102271115A (en) * | 2011-08-22 | 2011-12-07 | 宁波大学 | Anti-noise transmission method of digital broadcasting mobile signals |
| CN102271116A (en) * | 2011-08-22 | 2011-12-07 | 宁波大学 | Anti-fading multimedia wireless broadcast signal framing modulation method |
| CN102271111A (en) * | 2011-08-22 | 2011-12-07 | 宁波大学 | Anti-fading mobile multimedia broadcasting signal framing modulation method |
| CN102299890A (en) * | 2011-08-22 | 2011-12-28 | 宁波大学 | Multimedia broadcasting wireless signal anti-interference framing modulation method |
| CN101378379B (en) * | 2007-08-29 | 2013-02-06 | 株式会社东芝 | Transmitter |
| CN103763244A (en) * | 2014-01-13 | 2014-04-30 | 宁波大学 | Framing modulation method for multimedia wireless broadcast signals |
| CN103763269A (en) * | 2014-01-13 | 2014-04-30 | 宁波大学 | Anti-noise mobile multimedia broadcast signal framing modulation method for single-frequency network |
| CN105052102A (en) * | 2012-11-30 | 2015-11-11 | 高通股份有限公司 | Systems and methods for phase rotating duplicate frames in wireless lan transmissions |
-
2006
- 2006-05-22 CN CN 200610081461 patent/CN1885846A/en active Pending
Cited By (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101378379B (en) * | 2007-08-29 | 2013-02-06 | 株式会社东芝 | Transmitter |
| CN101431505B (en) * | 2008-12-03 | 2011-08-31 | 山东大学 | Emission system and method for reducing peak-to-average power ratio of orthogonal frequency division multiplexing system |
| CN101478520B (en) * | 2008-12-15 | 2011-08-03 | 北京创毅视讯科技有限公司 | Descramble method and apparatus |
| CN102273158A (en) * | 2008-12-31 | 2011-12-07 | 高通股份有限公司 | Methods and systems for papr reduction in sc-fdma systems |
| CN101848184B (en) * | 2010-06-03 | 2013-04-03 | 山东大学 | Selective mapping scrambling method for reducing peak-to-average power ratio of orthogonal frequency division multiplexing system |
| CN101848184A (en) * | 2010-06-03 | 2010-09-29 | 山东大学 | Selective mapping scrambling method for reducing peak-to-average power ratio of orthogonal frequency division multiplexing system |
| CN102299890A (en) * | 2011-08-22 | 2011-12-28 | 宁波大学 | Multimedia broadcasting wireless signal anti-interference framing modulation method |
| CN102263761B (en) * | 2011-08-22 | 2013-06-12 | 宁波大学 | Method for modulating framing of multimedia wireless broadcast signals |
| CN102271116A (en) * | 2011-08-22 | 2011-12-07 | 宁波大学 | Anti-fading multimedia wireless broadcast signal framing modulation method |
| CN102271111A (en) * | 2011-08-22 | 2011-12-07 | 宁波大学 | Anti-fading mobile multimedia broadcasting signal framing modulation method |
| CN102271117A (en) * | 2011-08-22 | 2011-12-07 | 宁波大学 | Anti-interference multimedia wireless broadcast signal framing modulation method |
| CN102263761A (en) * | 2011-08-22 | 2011-11-30 | 宁波大学 | Method for modulating framing of multimedia wireless broadcast signals |
| CN102263765A (en) * | 2011-08-22 | 2011-11-30 | 宁波大学 | Robust transmission method of digital broadcast mobile signals |
| CN102271115A (en) * | 2011-08-22 | 2011-12-07 | 宁波大学 | Anti-noise transmission method of digital broadcasting mobile signals |
| CN102271111B (en) * | 2011-08-22 | 2013-06-26 | 宁波大学 | Anti-fading mobile multimedia broadcasting signal framing modulation method |
| CN102271117B (en) * | 2011-08-22 | 2013-06-26 | 宁波大学 | Anti-interference multimedia wireless broadcast signal framing modulation method |
| CN102263765B (en) * | 2011-08-22 | 2013-07-10 | 宁波大学 | Robust transmission method of digital broadcast mobile signals |
| CN102271115B (en) * | 2011-08-22 | 2013-07-10 | 宁波大学 | Anti-noise transmission method of digital broadcasting mobile signals |
| CN102299890B (en) * | 2011-08-22 | 2013-08-07 | 宁波大学 | Multimedia broadcasting wireless signal anti-interference framing modulation method |
| CN105052102A (en) * | 2012-11-30 | 2015-11-11 | 高通股份有限公司 | Systems and methods for phase rotating duplicate frames in wireless lan transmissions |
| CN103763244A (en) * | 2014-01-13 | 2014-04-30 | 宁波大学 | Framing modulation method for multimedia wireless broadcast signals |
| CN103763269A (en) * | 2014-01-13 | 2014-04-30 | 宁波大学 | Anti-noise mobile multimedia broadcast signal framing modulation method for single-frequency network |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1885846A (en) | Orthogonal frequency-division multiplexing system and selective mapping transmitting and receiving method | |
| US7376074B2 (en) | Apparatus and method for transmitting and receiving side information of a partial transmit sequence in an OFDM communication system | |
| CN1666452A (en) | Apparatus and method for transmitting and receiving side information about selective mapping in an orthogonal frequency division multiplexing communication system | |
| US7269782B2 (en) | Orthogonal frequency division multiplexing/modulation communication system for improving ability of data transmission and method thereof | |
| CN101848184B (en) | Selective mapping scrambling method for reducing peak-to-average power ratio of orthogonal frequency division multiplexing system | |
| CN1694444A (en) | Radio communication system, radio transmitter and radio receiver | |
| CN1956433A (en) | Multi-carrier communication system | |
| KR20050026285A (en) | Apparatus and method for reducing peak to average power ratio in orthogonal frequency division multiplexing communication system | |
| CN1684455B (en) | System and method for spreading on fading channels | |
| CN107800662A (en) | A kind of method for reducing spread spectrum OFDM signal papr | |
| CN102821080A (en) | Receiving method for bandwidth expansion of 1553B communication bus | |
| EP2491692A1 (en) | A communications system utilizing orthogonal linear frequency modulated waveforms | |
| CN1984110B (en) | Method for decreasing peak equilibrium ratio and orthogonal frequency division multiplexing system | |
| CN101771644A (en) | Joint detection and soft decision decoding-based signal receiving method | |
| WO2008156338A1 (en) | Method and apparatus for transmitting uplink control channel in a mobile communication system | |
| CN110519006B (en) | Single carrier interleaving type frequency division multiple access signal transmission method based on symbol shortening | |
| KR100842069B1 (en) | COFDM transmission system add pilot signal in frequence domain and a method proessing OFDM signal thereof | |
| CN101483449B (en) | Multiuser transmission method and transmission apparatus | |
| KR20040035288A (en) | Multi-carrier transmission system capable of improving the performance of receiving and a method proessing signal thereof | |
| CN1433168A (en) | Channel noise resisting balance method based on Walsh transformation for orthogonal frequency-division multiplexing system | |
| KR100884407B1 (en) | TDS-OFDM transmission system having 3780-????? ????/??? procseeor and structure of 3780- ?? procseeor | |
| KR101209259B1 (en) | Transmitter and receiver of ofdma system with channel capacity increment using group orthogonal code and binary value | |
| KR20040056791A (en) | Apparatus and method for reducing peak to average power ratio in ofdm communication system | |
| CN101471911A (en) | Transmission and receiving device of OFDM system in Quick-Change channel circumstance | |
| KR100920722B1 (en) | Multi-carrier transmission system capable of improving the performance of receiving and a method proessing signal thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Open date: 20061227 |