CN103812814B - Coding/decoding method, receiver, device, ofdm communication system and computer program product - Google Patents
Coding/decoding method, receiver, device, ofdm communication system and computer program product Download PDFInfo
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Abstract
Disclose a kind of coding/decoding method, receiver, device, ofdm communication system and computer program product.Describe the method that the SC-FDMA symbol received is decoded in the receiver of ofdm communication system.The described method includes: from the channel matrix H of all subcarrier ii, noise covariance matrix S and constellation energy approximate with the associated digital power signal Matrix C calculating of the SC-FDMA symbol receivedThe approximation constellation energy is calculated according to following expressions: The method also includes using associated approximate constellation energyDecode the symbol received.In addition, also describing receiver, device, ofdm communication system and being used for this decoded computer programmed product.
Description
Technical field
The present invention relates to a kind of method of SC-FDMA symbol for decoding and receiving in the receiver of ofdm communication system,
Constellation statistical counter, receiver, device, ofdm communication system and be used for this decoded computer program product.
Background technique
Long Term Evolution (LTE) has stepped a nearest step in mobile phone 3G service.There is provided up to 50,000,000 ratios by LTE
The 3GPP standard of the downlink speed of the uplink speed and up to 100Mbps of special (Mbps) per second.LTE physical layer be
The efficient way of both data and control informations is transmitted between enhanced base station (eNodeB) and mobile subscriber equipment (UE).
LTEPHY uses orthogonal frequency division multiplexing (OFDM) and multiple-input and multiple-output (MIMO) data are transmitted.In particular, LTE PHY is used
Two kinds of OFDM scheme: in the orthogonal frequency division multiple access (OFDMA) and uplink route (UL) on downlink (DL)
Single carrier wave-frequency division multiple access (SC-FDMA).OFDMA allows in the code-element period specified number in the basic of subcarrier one by one
On to from multiple user's directional datas.SC-FDMA is also referred to as term " single carrier wave-orthogonal frequency division multiple access (SC-OFDM) ".
Available bandwidth is divided into many relatively narrow subcarriers and emits data with parallel stream by ofdm system.Every height carries
Wave is modulated by using the QAM modulation of different level, depend on signal quality, such as can be QPSK, QAM, 64QAM or
Person can be can higher order.Therefore, each OFDM symbol is the linear combination of the transient signal in channel on each subcarrier.
The front end of each OFDM symbol is cyclic prefix (CP), which be used to effectively eliminate ISI.In addition, son carries
Wave is closely spaced, and efficiently to utilize available bandwidth, and interference (carrier wave is practically without between adjacent subcarrier
Between interfere or ICI).OFDM symbol includes two primary clusterings: CP and FFT period (TFFT).There is the abundant duration
CP, front end symbol did not overflowed in the FFT period；It only exists and is interfered as caused by the time interleaving " copy " of current symbol.
Once channel impulse response is determined (using the periodic transfer of known reference signal, referred to as pilot frequency code element), distortion can lead to
Cross being substantially corrected using amplitude and phase-shifts in subcarrier one by one.
In LTE downlink, OFDMA is used as multiplexing scheme.In ofdma, user is in predetermined time amount
Certain number of subcarrier is assigned.These are referred to as Physical Resource Block (PRB) in LTE specification.Therefore, when PRB has
Between and frequency dimension.The distribution of PRB is disposed by the scheduling feature of the base station 3GPP (eNodeB).The duration of LTE frame is 10
Millisecond.They are divided into 10 subframes, a length of 1.0 milliseconds of each subframe.Each subframe is also further divided into two time slots, often
It is a that there is 0.5 millisecond of duration.Time slot includes 6 or 7 ODFM symbols, this depends on conventional or extended cyclic prefix
Whether (being also hereinafter referred to as short and long CP) is used.Available total number of sub-carriers depends on the entire transmission bandwidth of system.LTE
Specification defines the parameter of system bandwidth: 1.25MHz-20MHz according to Physical Resource Block (PRB) bandwidth and available PRB number.
PRB is defined as including 12 continuous subcarriers for the duration of a time slot (0.5 millisecond).PRB is dispatched by base station
The least member of the resource allocation of device assignment.The down link signal of transmitting is in NsymbInclude in the duration of a OFDM symbol
NBWA subcarrier.It can be indicated by so-called resource grid.Each frame in resource grid indicates to be used for a code-element period
Single subcarrier and referred to as resource element.Note that having resource grid for each transmitting antenna in MIMO application
Lattice.Special reference signal is embedded into PRB.When short CP is used, reference signal is the first of each time slot and
It is launched during five OFDM symbols, and when long CP is used, reference signal is the first of each time slot and the 4th
It is launched during OFDM symbol.Note that every 6th subcarrier transmits reference symbols sn.In addition, reference symbols sn is in time and frequency
All interlock in rate.The channel response carried on the subcarrier of reference symbols sn can directly fall into a trap from received reference symbols sn
It calculates.Interpolation be used to eliminate the channel response on remaining subcarrier.
Multiple transceivers are used to the LTE PHY property of can choose in base station and UE, to enhance link robustness and raising
The data rate of LTE downlink.In particular, when the intensity of signal is low and multipath condition is challenging, it is maximum
Ratio merges (MRC) and be used to enhance link reliability in terms of challenging propagation conditions.MIMO is used to improve system data
The relevant technologies of rate.In order to receive MIMO transmission, receiver determines the channel impulse response for being originated from each transmitting antenna.?
In LTE, channel impulse response is determined by continuously emitting known reference signal from each transmitting antenna.For example, being sent out in Lx=2
In emitter × Lx=2 receiver mimo systems, there are four channel impulse response (C1, C2, C3 and C4) in total.Pay attention to when a hair
When reflector antenna is sending reference signal, other antennas are in idle condition.Once channel pulse signal be it is known,
Data can emit simultaneously from all antennas.The linear combination of two data streams at two receiver antennas results in two
The set of equation and two unknown numbers can be broken down into two original data streams.
In view of reducing power consumption, single carrier wave-frequency division multiple access (SC-FDMA) technology is used for uplink, using as quilt
The substitution of OFDMA for LTE downlink.Basic transmitter and receiver architecture are closely similar (almost the same) with OFDMA,
And it provides the multipath protection of substantially the same degree.In SC-FDMA, bottom waveform can substantially be considered as
Single carrier wave.
Fig. 1 schematically shows basic SC-FDMA emitter/receiver arrangement.Pay attention to many functional blocks to SC-FDMA
Be common for OFDMA, therefore there are the function general character of significance degree between uplink and down link signal chain.
Functional block in the transmitting chain of uplink route includes:
1. constellation mapper: incoming bit stream being converted into single carrier wave symbol and (depends on channel condition, BPSK, QPSK
Or 16QAM)；
2. serial/parallel converter: time domain SC symbol format is turned to the block for being used to be input to FFT engine；
3.M point DFT (also referred to as fft block): time domain SC block of symbols is converted into M discrete tone；
4. subcarrier maps: by DFT output Tone Map to specified subcarrier, to be used for transmission.Specified subcarrier is frame
In NscThe subset of a continuous subcarrier, is referred to as distributed；
5.N point IDFT: the subcarrier after mapping is converted into time domain, to be used for transmission；And
6. cyclic prefix and shaping pulse: cyclic prefix is preset (prepend) to SC-FDMA symbol, with with description
The identical mode of OFDM is immune to provide multipath.As in the example of OFDM, shaping pulse be used to prevent spectral re-growth；
7.RFE: converting digital signals into analog signal, and upconvert to RF, to be used for transmission.
Constellation mapper, serial/parallel converter, M point DFT and subcarrier maps can be collectively known as modulator.
In MIMO application, constellation mapper, serial/parallel converter and M point DFT are provided to parallel each biography
Enter bit stream and subcarrier maps include: by the DFT of the different M point DFT on Lx emitter antenna export Tone Map to by
The so-called layer of MIMO coder block, and DFT output tone is mapped to identical specified subcarrier.In multiuser MIMO (MU-
MIMO in), antenna is related from different UE terminals.In sole user MIMO (SU-MIMO), transmitting antenna and identical UE are whole
It holds related.
In receiving side chain, process is substantially opposite.As in the example of OFDM, SC-FDMA transmission can be recognized
For the linear superposition for being discrete subcarrier.Multipath distortion with substantially similar way in downlink OFDMA system to be located
It sets and (removes CP, be converted into frequency domain, channel correction is then applied on the basis of subcarrier one by one).It is different from OFDMA, by discrete
The bottom SC-FDMA signal that subcarrier indicates is single carrier wave.
In the uplink, data are mapped on signal constellation (in digital modulation), can be depending on signal constellation (in digital modulation) described in channel quality
QPSK, 16QAM or 64QAM.Fig. 6 schematically show for QPSK (left side), 16QAM (in) and 64QAM (right side) constellation
Figure.However, from the direct modulated sub-carriers of QPSK/QAM symbol (as the example in OFDMA) different, uplink symbols are used
It is sequentially fed to serial/parallel converter, and then arrives fft block just as shown in Figure 1 (for executing M point DFT).
It is at fft block output the result is that the discrete frequency domain of QPSK/QAM sequence of symhols indicates.(N point is used before converting back time domain
IDFT, also referred to as IFFT), the discrete fourier item at fft block output is then mapped into subcarrier.Final step before transmission
It suddenly is exactly additional CP.
Fig. 1 also schematically shows receiver-side REC, and the functional block in reception chain is:
1.RFD: RF signal is converted into digital signal.
2. cyclic prefix removes: cyclic prefix is removed, to retain only received signal vector y associated with the FFT period；
3.N point DFT: received signal vector y is converted into associated mapping in frequency domain from the time domain being used for transmission and is carried
Wave；
4. frequency domain processor: executing in a frequency domain balanced and calculate the statistics used in demodulator.It is applied in MIMO
In, the multiple Rx receiver antenna streams of demapping are also executed by frequency domain processor.In MIMO application, which gives every layer
Provide signal stream；
5.M point IDFT: domain symbol block is converted back.
6. parallel/serial converter: time domain SC symbol format is turned to the block for being used to be input to FFT engine；
7. decoder: by SC symbol decoding at the bit stream of information bit.
M point IDFT, parallel/serial converter and decoder can be collectively known as demodulator.In MIMO application, M
Point IDFT, parallel/serial converter and decoder are provided to each layer.
Cyclic prefix removes and N point DFT block executes the circulation of antenna input sample for each OFDMA/SC-FDMA symbol
Prefix removes and discrete fourier conversion (DFT).Each DFT input sample can be referred to as subcarrier.It is defined according in standard
System bandwidth determine DFT size N.
Fig. 2 schematically shows that the frequency domain processor FDPP's of uplink chain just as shown in Figure 1 is further
Details.
The frequency domain processor FDPP of receiver-side is arranged to: by making known to DFT output and each SC-FDMA symbol
Emit pilot frequency sequence association, Lai Zhihang channel and noise estimation, to obtain the channel response of estimation and the noise variance of estimation.Estimate
The channel response of meter is typically denoted as channel response matrix H and noise variance matrix S.To each SC-FDMA symbol and each
Subcarrier estimates channel response and noise variance.Frequency domain processor further includes frequency domain equalizer, which is arranged to
Balanced DFT output, to inhibit to carry out channel effect by using the noise variance of the channel response of estimation and estimation.Balanced device can
To be arranged to: according to such as linear MMSE criterion (LMMSE) or being based on Interference Cancellation and linear least mean-square
The equalization algorithm of error criterion offsets MMSE (SIC-MMSE) criterion according to such as stepwise derivation or according to Parallel Interference Cancellation
MMSE (PIC-MMSE) criterion is come balanced.These and other balanced device and criterion are well-known to those skilled in the art
And be therefore not described in detail herein.
Shown prior art frequency domain processor FDPP further includes constellation statistics calculator CSCP.Constellation statistics calculates
Device CSCP may use the channel response of estimation and the noise variance of estimation calculate the mean power of constellation and balanced and
The mean power of the interference received after the IDFT stage.The mean power of constellation may be also known as constellation power or constellation energy
Measure K.The mean power of interference may be also known as constellation noise variance or jamming power U.Constellation power or constellation energy K and
Constellation noise variance or jamming power U may also be referred to as constellation statistics.
The demodulator of receiver-side, which is arranged to using constellation power K and constellation noise variance U, decodes IDFT output solution
Code, to obtain the information bit of each SC-FDMA symbol.Here demodulator may include constellation demapper and decoder.
The constellation demapper and decoder are likely to form integrated package, or may be provided as individual block.Constellation demapper
Item demapper can be referred to as.Demodulator may include Turbo decoder.One example of Turbo decoder is for example
“Gilberto Berardinelli,Carles Navarro Manch′on,Luc Deneire,Troels B.Preben Mogensen,Kari Pajukoski,“Turbo Receivers for Single User
MIMO LTE-A Uplink " (the Turbo receiver for sole user's MIMO LTE- uplink), IEEE69th
It is described in Vehicular Technology Conf., April2009.pp.1-5 (being also known as Berardinelli) ".It goes
Mapper is calculated using K and U to be needed for decoded log-likelihood ratio measurement (LLR).Demodulator alternatively may include
Based on the Euclidian decoder of maximum likelihood, (decoder sides are such as used for so-called Randt's Miller decoder (Reed-Muller
Decoder the LTE in)).It is this that IDFT output signal is being calculated using K based on the Euclidian decoder of maximum likelihood
And assume that adjusting normalized constellation between signal before distance assumes.Multiple Turbo decoders, based on maximum likelihood Europe it is several in
The decoder and other decoders obtained is well known in the art.
Optimal or traditional and different receiver algorithm is described in the literature.For example, " Narayan
Prasad,Shuangquan Wang,and Xiaodong Wang,“Efficient Receiver Algorithms for
DFT-Spread OFDM Systems (effective receiver algorithm of DFT propagation ofdm system) ", IEEE TRANSACTIONS
ON WIRELESS COMMUNICATIONS, VOL.8, NO.6, JUNE2009, p.3216-3225 " article by alternate algorithm with
Traditional algorithm is compared.The receiver algorithm requirement largely proposed is largely carried out resource.
Summary of the invention
As described in appended claims, the present invention provides a kind of to solve in the receiver of ofdm communication system
The method of SC-FDMA symbol that code receives, constellation statistics calculator, receiver, device, ofdm communication system and for this
The decoded computer program product of kind.
Specific embodiments of the present invention are stated in the dependent claims.
According to embodiments described hereinafter, of the invention these or other aspects will be apparent that and are set forth.
Detailed description of the invention
With reference to the accompanying drawings, only by example way, further details of the invention, aspect and embodiment will be described.
For simplicity and clearly, the element in attached drawing is not drawn necessarily to scale.
Fig. 1 schematically shows the example of SC-FDMA emitter/receiver arrangement；
Fig. 2 schematically shows the example of frequency domain processor；
Fig. 3 schematically shows the example of the calculating of constellation statistics；
Fig. 4 schematically shows the example of the performance of exemplary algorithm；
Fig. 5 schematically shows receiver；
Fig. 6 schematically shows the planisphere of LTE；
Fig. 7 schematically shows communication system；And
Fig. 8 show include computer program product computer-readable medium.
Element explanation in attached drawing is for simplicity and clearly, to be not drawn necessarily to scale.In the accompanying drawings, correspond to
The element for the element being described may have identical reference symbols sn.
Specific embodiment
Art methods described in introduction of the present invention and receiver may use traditional receiver algorithm, wherein
Constellation statistics is calculated according to so-called optimal algorithm.
According to optimal algorithm, from all N of distributionscThe channel matrix H of a subcarrier ii, wherein i=0 ... Nsc, noise association
Variance matrix S and digital power signal Matrix C calculate optimal star according to following expressions for each SC-FDMA symbol
Seat energy KoptWith optimal constellation variance Uopt:
By optimal algorithm, in all subcarriers 1 ... N of distributionscOn be averaged.According to known method, channel matrix
Hi, noise covariance matrix S and data-signal power matrix C can obtain from channel and noise estimation.Channel matrix HiRuler
Very little to can be Rx × Lx, the size of noise covariance matrix S can be Rx × Rx and the size of data signal power Matrix C can
To be Lx × Lx, wherein Lx, which corresponds to, corresponds to receiver antenna number for the transmitting antenna number and Rx of MIMO communication.
Data signal power Matrix C is the diagonal matrix having a size of Lx × Lx, and wherein Lx is transmitting antenna number.Data signal power square
The diagonal element of battle array C keeps the mean power of associated layer.In LMMSE equalization scheme, data signal power Matrix C be can be
Unit matrix.In interference cancellation scheme, such as in SIC-MMSE and PIC-MMSE, according to certain interference counteracting method, number
It is believed that number power matrix C can be obtained according to known technology.
Fig. 3 schematically shows the example of the calculating of constellation statistics according to one embodiment.
In the first stage in 11, this method receives all N of distributionscThe channel matrix H of a subcarrier ii, wherein i=0 ...
Nsc, and noise covariance matrix S.According to known method, channel matrix HiIt can be from channel and making an uproar with noise covariance matrix S
It is obtained in sound estimation.Channel matrix HiSize can be Rx × Lx, the size of noise covariance matrix S can be Rx × Rx,
Wherein Lx, which corresponds to, corresponds to receiver antenna number for the transmitting antenna number and Rx of MIMO communication.In second stage 12
In, this method calculates the variable Q of each subcarrier i of distribution according to following expressionsi:
In the phase III 13, this method calculates all subcarrier i=0 ... N in distributionsc, the variable Q of upper calculatingi's
Average value, to obtain average valueIn this regard, the stage 13 calculates:
In fourth stage 14, this method obtains data signal power Matrix C.In this regard, fourth stage 14 may use
Technology is known to obtain the data signal power Matrix C.As described above, data signal power Matrix C can be LMMSE equalization scheme
In unit matrix.In interference cancellation scheme, such as in SIC-MMSE and PIC-MMSE, data signal power Matrix C can
To be different from the unit matrix.The size of data signal power Matrix C can be Lx × Lx, and wherein Lx corresponds to logical for MIMO
The transmitting antenna number of letter.
In the 5th stage, this method is according to following expressions from average valueIt is calculated with data-signal power matrix C close
Like constellation energy
Therefore, approximate algorithm has been efficiently used in this method, which, which is arranged to, calculates the close of each SC-FDMA symbol
It is counted like constellation.According to the approximate algorithm, according to following expressions, from the channel matrix H of all subcarrier ii, noise covariance
Matrix S and data-signal power matrix C calculates approximate constellation energy
The approximation constellation energy used in approximate algorithmFormula can be with the optimal star used in optimal algorithm
Seat energy KoptIt is compared, when according to variable QiWhen being rewritten, which becomes:
Compare these formula and shows that known formula determines all matrix diag ((Q of each subcarrier firsti+C-1)- 1Qi), then these results are equalized, however all Q of the approximate algorithm first on sub-carriersiOn average,
Then its diagonal matrix diag is determined.Therefore, the approximate algorithm needs less matrix manipulation and ought be real in software
When applying, it might therefore cause to implement and/or cycle count complexity is remarkably decreased.
As the 6th stage 16, this method may give decoder (such as maximum likelihood decoder or demapping and Turbo
Decoder or another demodulator) approximate constellation energy is providedTo obtain signal bit.
According to further embodiments, the 5th stage also calculated approximate constellation variance according to following expressions
This can be with optimal constellation variance UoptKnown formula be compared, according to variable QiIt is rewritten:
Again, it is shown when implementing in software in the optimal comparison between approximate algorithm formula, closely
The implementation and/or cycle count complexity that may need to be remarkably decreased like algorithm.
In a further embodiment, the 6th stage 16 also may provide approximate constellation variance to decoderWhen decoded
When, which then may be also using approximate constellation variance
This method may further include the next stage 20, which includes using associated approximate constellation energyIt is connect to decode
The symbol received.Decoding the symbol received may be also using approximate constellation variance
The decoding may include Turbo decoding.The decoding may include based on the Euclidian decoding of maximum likelihood.
This method may further include at least one or more SC-FDMA pilot frequency code element received from channel matrices estimation
Determine the channel matrix H of all subcarrier ii, and it is true from least one or more described SC-FDMA pilot frequency code element for receiving
The fixed noise covariance matrix.It therefore, can be every based on the SC-FDMA pilot frequency code element that at least one or more is received
A SC-FDMA symbol executes channel matrix HiWith the estimation of noise covariance matrix S.For example, a subframe can be by 14 codes
Member composition: UE transmitted in 12 symbols will decoded data and UE transmit pilot frequency code element in 2 symbols,
These pilot frequency code elements are known for base station and can be associated with data to decode by base station for estimating H and S
12 symbols.
This method may further include that the SC-FDMA symbol received from least one or more determines data signal power square
Battle array C.
Receiver can be LTE receiver and ofdm communication system can be LTE communication system.
Fig. 4 shows the comparison of optimal algorithm and approximate algorithm simulation.Horizontal axis indicate in considered bandwidth with dB table
The signal-to-noise ratio (SNR) shown.The longitudinal axis indicates block error rate (BLER).Simulation is by using 16-QAM modulation, SIC-MMSE equilibrium, 2
Transmitter × 2 receiver MIMO application, the definition in 136 104 V10.7.0 (2012-07) of 3GPP normative document ETSI TS
EVA-70Hz fading channel model be performed, " LTE;Evolved Universal Terrestrial is wirelessly electrically accessed (E-UTRA);Base station (BS) is wireless
Electricity transmitting and reception (36.104 version 10.7.0Release 10 of 3GPP TS) ", 0.75 code rate and each subframe 100
A distribution.Curve BND indicates K=U=1 and is used as referring to.Curve OPT indicates optimal algorithm.Curve APR indicates approximate and calculates
Method, can be it is observed from fig. 1 that the performance of approximate algorithm and the performance of optimal algorithm be essentially the same.
Compared with optimal algorithm, approximate algorithm has the complexity of decline.This can be for example by comparing for executing algorithm
Resource requirement illustrate.The each subframe of the example of comparison given below uses 12 SC-FDMA data symbols, per second 100
The system bandwidth of a subframe and 20MHz.
Indicated with millions of circulations (MCPS) per second, for this example, three different Lx × Rx (1 × 2,2 × 2,
2 × 4) in MIMO situation, optimal algorithm needs:
Wherein NscIndicate number and N that sub-carriers are distributed at oneocIt is the subcarrier occupied in whole bandwidth
Number.Number 12 in formula indicates 12 SC-FDMA data symbols of each subframe.Therefore, in 20MHz, Noc=
1200, i.e. 1200 subcarriers occupied.The item Lx of U in formula4Corresponding to operand needed for Lx × Lx matrix of inverting
Mesh.The item Lx of K in formula3Corresponding to operation number needed for multiplication Lx × Lx matrix.
For approximate algorithm, matrix inversion and matrix multiple execute in each distribution, each code element and this example
Resource requirement be:
Wherein NallocIndicate the number of the distribution of each subframe, this corresponds to N for shown MPCSalloc=100, i.e., each
100 distribution of 12 subcarriers of subframe.Again, the number 12 in formula indicates 12 SC-FDMA of each subframe
Data symbols, the item Lx of the U in formula4Item corresponding to the K in operation number and formula needed for Lx × Lx matrix of inverting
Lx3Corresponding to operation number needed for multiplication Lx × Lx matrix.
It may be noted that being accordingly used in average since this operation can be performed in the case where no additional MCPS
MPCS do not include neither approximate algorithm be also not optimal algorithm MPCS count in.
Therefore, approximate algorithm may be than operation number that optimal algorithm has needed to be remarkably decreased (reducing 90%).Fewer number of
Operation the implementation of software may be allow to program in microcontroller in Programmable DSPs is feasible.What approximate algorithm reduced answers
Miscellaneous degree may alternatively and/or extraly allow reduce the size hardware implement, therefore reduce semiconductor device area and
Reduce correlative charges.
Fig. 5 according to one embodiment, schematically show include frequency domain processor FDPE receiver.Similar to drawing
Described prior art receiver is called the turn, which further includes the RF letter for will receive from one or more antennas
Number be converted into the RFD unit of digital signal, for removing cyclic prefix to retain an only received signal vector related with the FFT period
The CP of y removes the N point of unit and the associated mapping subcarriers for being converted into received signal vector y from time domain in frequency domain
DFT unit.Frequency domain processor FDPE includes channel and noise estimator and frequency domain equalizer, these likely correspond to existing skill
Art channel and noise estimator and prior art frequency domain equalizer, for example, referring to described in Fig. 2.According to one embodiment,
Frequency domain processor FDPE further includes constellation statistics calculator CSCE.Constellation statistics calculator CSCE can also be referred to as constellation
Statistic unit CSCE.According to any of the above embodiments, constellation statistics calculator CSCE is arranged to execution and calculates approximate star
Seat energyAnd optionally calculate approximate constellation varianceMethod.Therefore, in one embodiment, constellation statistics calculates
Device CSCE can be arranged calculating and provide approximate constellation energyAnd approximate constellation varianceReceiver may include
Programmable processor.The programmable processor can be arranged execution program code, and said program code includes instruction, described
Instruction causes programmable processor to execute the method according to any of the above embodiments, or at least calculates approximate constellation energy
AmountAnd optionally calculate approximate constellation varianceThe processor, which may include, to be particularly designed for executing this method
Semiconductor circuit.The receiver can be LTE receiver.
Fig. 7 schematically shows communication system COMSYS according to one embodiment.Communication system COMSYS can be
LTE system.Communication system COMSYS includes enhanced base station eNB and user equipment (UE).According to above-described embodiment, enhanced base station
ENB may include constellation statistic unit CSCE.Additionally or alternatively, according to above-described embodiment, user equipment (UE) be may include
Constellation statistic unit CSCE.
Therefore, on the one hand provide include above-mentioned receiver device.The device can be enhanced base station eNodeB.
The device can be user equipment (UE).
The device can be include base station receiver enhanced base station eNB, wherein the base station receiver include by
It is arranged to calculate approximate constellation energy as described aboveWith approximate constellation varianceConstellation statistic unit CSCE and by cloth
It is set to using approximate constellation powerWith approximate constellation noise varianceObtain the constellation of the information bit of each SC-FDMA symbol
Demapper.
The device can be include UE receiver user equipment (UE), wherein the UE receiver includes being arranged to meter
Calculate approximate constellation energy as described aboveWith approximate constellation varianceConstellation statistic unit CSCE and be arranged to use
Approximate constellation powerWith approximate constellation noise varianceObtain the constellation demapping of the information bit of each SC-FDMA symbol
Device.
On the one hand provide include enhanced base station (eNodeB) eNB and user equipment (UE) communication system, eNodeB
It include being arranged to calculating approximate constellation energy as described above at least one of UEWith approximate constellation varianceStar
Seat statistic unit CSCE.
The communication system can be ofdm communication system.
Fig. 8 show include computer program product 3100 computer-readable medium 3000.Computer program product
3100 include that processing unit is caused to execute the method for decoding the SC-FDMA symbol received in the receiver of ofdm communication system
Instruction.Computer program product 3100 may further include the other processing stages for causing the processor device to execute reception chain,
Such as frequency domain processing.Computer program product 3100 can be used as physical markings or the magnetization by computer-readable medium 3000
Mode is presented on computer-readable medium 3000.However, it is also contemplated that any other suitable embodiment.Further, it should be appreciated that
Although computer-readable medium 3000 shows that in fig. 8 computer-readable medium 3000 can be any suitable as CD
Computer-readable medium, such as hard disk, solid-state memory, flash memory etc., and can be unrecordable or can recorde
's.
Therefore, the present invention can be implemented in computer program.The program for running on the computer systems, at least
Including for when in programmable device, such as computer system or starting programmable device are to execute device according to the present invention
Or the function of system, when operation, execute a kind of code section according to the method for the present invention.Computer program may be for example including
It is one or more: subprogram, function, programs, objects method, object implementatio8, executable application program, small routine, small service
Program, source code, object identification code, shared library/dynamic loading library and/or designed for the other of execution on the computer systems
Instruction sequence.Computer program may be provided in data medium, such as store on the CD-rom or disk of data, the number
According to that can be loaded into the memory of computer system, which indicates computer program.The data medium can still data connect
It connects, such as telephone cable or wireless connection.
In the foregoing description, referring to the specific examples of the embodiment of the present invention, invention has been described.However,
The wide scope spirit and model of the invention that apparent various modifications and variations can be stated in not departing from appended claims
It is made in the case where enclosing.For example, these connections can be any kind of connection.The connection be suitable for by signal from or be transferred to
Respective node, unit or device, such as pass through intermediary device of perforating.Therefore, unless implying or illustrating, connection, for example, it may be possible to
It is connected directly or indirectly.
The conductor that the present invention is discussed can be illustrated about plain conductor, multiple conductors, unidirectional conductor or bidirectional conductors
Or description.However different embodiments may change the realization of conductor.Such as independent unidirectional conductor can be used rather than two-way
Conductor, vice versa.In addition, multiple conductors, which may alternatively be, transmits multiple signals continuously or in a manner of time multiplexing
Plain conductor.Similarly, the plain conductor for carrying multiple signals can be separated into a variety of different these signals of carrying
The conductor of subset.Therefore, there are many options of transmission signal.
As implement utensil of the invention be largely the electronic component as known to those skilled in the art and
The details of circuit composition, circuit will not be solved in any degree bigger than the above-mentioned illustrated degree felt the need to
It releases.Understanding and understanding to basic conception of the present invention are in order not to obscure or deviate the content that the present invention is taught.
About specific conduction type or polarities of potentials, although the present invention has been described, technical staff know conduction type and
Polarities of potentials can be opposite.
In addition, term " front ", " back ", " top ", " bottom " in described and claimed, " above ", " under
Face " etc., if any, be for descriptive purposes and not necessarily for the permanent relative position of description.Ying Liao
This usage of solution term be in appropriate circumstances can be interchanged so as to embodiment described in the invention for example, can be
It operates illustrated by other directions rather than the present invention or in other aspects.
Term " program " used in the present invention is defined as the sequence designed for executing instruction on the computer systems
Column.Program or computer program may include one or more: subprogram, function, programs, objects method, object implementatio8, can
Application program, small routine, servlet, source code, object identification code, shared library/dynamic loading library and/or the design of execution are used
In other instruction sequences of execution on the computer systems.
Above-mentioned some embodiments can be carried out if applicable by using a variety of different information processing systems.
Although the exemplary architecture is presented that this is being discussed for example, Fig. 1 and its discussion describe example information processing structure
The various aspects of invention provide useful reference.Certainly, in order to discuss, the description of the framework has been simplified, also, this is
One of them many different types of suitable architecture that can be used according to the present invention.Those skilled in the art will recognize that
It is merely illustrative to the boundary between logical block and alternate embodiment may merge logical block or circuit element or each
Force the decomposition function of substitution on kind logical block or circuit element.
It is therefore to be understood that the framework that the present invention describes is only exemplary, and in fact realize many of identical function
Other frameworks can be implemented.It should be appreciated that circuit as described herein is exemplary.From abstract but still have in meaning
For, it is effective " association " to reach the arrangement of any element of identical function, to realize required function.It therefore, is real
The arrangement of any component of existing identical function effectively " is associated with " so that required function is achieved.Therefore, special to realize
Determine function, in the present invention combined any two component can be counted as each other " associated " so that required function obtains
To realize, no matter framework or intermediate module.Similarly, so associated any two component may be considered as each other by
" being operatively connected " or " operably coupled " is to realize required function.
In addition, those skilled in the art will be recognized that the boundary between the operating function of foregoing description is illustrative
's.The function of multiple operations, which can be combined into single operation and/or single operating function, can be distributed in additional operations
In.Moreover, alternate embodiment may include multiple examples of specific operation, and the sequence operated is in various other embodiments
It can change.
In addition, the present invention is not limited to the physical device or unit being implemented in non-programming hardware, but can also apply
In programming device or unit.These devices or unit pass through operation and are able to carry out required device function.The execution is root
It is carried out according to suitable program code.In addition, these devices can be physically dispersed on some devices, while functionally
As single device operation.Meanwhile the device for functionally forming individual device can be integrated in single physical device
In.Meanwhile unit in one or more semiconductor devices and circuit can be appropriately combined.
However, other modifications, variation and substitution are also possible.The description and the appended drawings accordingly are regarded as from illustrative
Rather than from stricti jurise.
In the claims, any reference symbols sn being placed between bracket is not interpreted as limiting claim.It is single
Word " comprising " those of is not excluded for listing the presence of step in claim after other elements are probable.In addition, used in the present invention
" a " or " an " be defined as one or more.Also, word such as "at least one" used and " one in the claims
Or multiple " should not be interpreted to imply that the other claim elements restriction introduced by indefinite article " a " or " an " is any
Other specific rights requirements.The specific rights requirement includes the right element to invention that these are introduced, the right member
Part not only includes such element.Even if in the same claim including introductory phrase " one or more " or " at least
One " and indefinite article, such as " a " or " an ".Using definite article and so.Unless otherwise indicated, using term such as " the
One " and " second " be for arbitrarily distinguish these terms description element.Therefore, these terms not necessarily indicate the time or
Other orders of priority of these elements.The fact that certain measures are listed in mutually different claim is not offered as these
The combination of measure is consequently not used for acquisition advantage.
Claims (14)
1. a kind of method for decoding the SC-FDMA symbol received in the receiver of ofdm communication system, which comprises
According to following expressions, from the channel matrix H of all subcarrier ii, noise covariance matrix S and received with described
The associated digital power signal Matrix C of SC-FDMA symbol, to calculate approximate constellation energy
Wherein, QiIt is the variable of each subcarrier i,It is the variable Q of each subcarrier iiAverage value, NscIt is of subcarrier i
Number, and
Use the associated approximate constellation energyTo decode the symbol received.
2. according to the method described in claim 1, further include: according to following expressions, calculate approximate constellation variance
And wherein, the step of symbol received described in decoding, also uses approximate constellation variance
3. according to method described in any one preceding claims, wherein the decoding includes that Turbo is decoded or based on most
The Euclidian decoding of maximum-likelihood.
4. method according to claim 1 or 2, wherein the receiver is LTE receiver and the ofdm communication
System is LTE communication system.
5. method according to claim 1 or 2, the method also includes:
The SC-FDMA pilot frequency code element received from least one determines the channel matrix H of all subcarrier ii, as channel
Matrix Estimation, and
The noise covariance matrix is determined from least one described SC-FDMA pilot frequency code element received.
6. according to the method described in claim 5, the method also includes: from least one described SC-FDMA code for receiving
Member determines the digital power signal Matrix C.
7. a kind of constellation statistics calculator (CSCE) for receiver in ofdm communication system, the constellation statistics calculator
(CSCE) it is arranged to: according to following expressions, from the channel matrix H of all subcarrier ii, noise covariance matrix S and with
The associated digital power signal Matrix C of the SC-FDMA symbol received, to calculate approximate constellation energy
Wherein, QiIt is the variable of each subcarrier i,It is the variable Q of each subcarrier iiAverage value, Nsc is subcarrier i
Number.
8. constellation statistics calculator (CSCE) according to claim 7, is also arranged to: being calculated according to following expressions
Approximate constellation variance
9. a kind of receiver (RECE) is arranged to execution method described in any one of -6 and/or packet according to claim 1
Constellation statistics calculator (CSCE) according to claim 7 or 8 is included, the receiver includes programmable processor, described
Programmable processor is arranged to execution program code, and said program code includes for causing the programmable processor to execute
The instruction of the method.
10. receiver according to claim 9, the receiver includes semiconductor circuit, and the semiconductor circuit is set
Meter is to execute the method.
11. the receiver according to any one of claim 9-10, the receiver is LTE receiver.
12. a kind of communication device, including constellation statistics calculator according to claim 7 or 8 (CSCE) or according to right
It is required that receiver described in any one of 9-11.
13. a kind of ofdm communication system, including at least one communication device according to claim 12.
14. a kind of computer-readable medium, store instruction, described instruction are used to cause processor system according to programmable thereon
The program code that can be performed in target (2), execution decode the SC-FDMA symbol received in the receiver of ofdm communication system
Method, the method is any one in -6 according to claim 1.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP12191704.1 | 2012-11-07 | ||
| EP12191704.1A EP2731289B1 (en) | 2012-11-07 | 2012-11-07 | Decoding of a received sc-fdma symbol in a receiver in a ofdm communication system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103812814A CN103812814A (en) | 2014-05-21 |
| CN103812814B true CN103812814B (en) | 2019-07-16 |
Family
ID=
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|---|---|---|---|---|
| CN101124796A (en) * | 2004-10-12 | 2008-02-13 | 高通股份有限公司 | Log-likelihood estimation based on channel estimation errors due to guard subbands |
| CN101584243A (en) * | 2007-01-18 | 2009-11-18 | 松下电器产业株式会社 | Radio communication method and radio communication device |
| CN101689951A (en) * | 2007-06-28 | 2010-03-31 | 松下电器产业株式会社 | Transmitter, transmitting method, receiver, and receiving method |
| EP2437401A1 (en) * | 2009-05-29 | 2012-04-04 | Panasonic Corporation | Wireless communication apparatus and frequency hopping method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101124796A (en) * | 2004-10-12 | 2008-02-13 | 高通股份有限公司 | Log-likelihood estimation based on channel estimation errors due to guard subbands |
| CN101584243A (en) * | 2007-01-18 | 2009-11-18 | 松下电器产业株式会社 | Radio communication method and radio communication device |
| CN101689951A (en) * | 2007-06-28 | 2010-03-31 | 松下电器产业株式会社 | Transmitter, transmitting method, receiver, and receiving method |
| EP2437401A1 (en) * | 2009-05-29 | 2012-04-04 | Panasonic Corporation | Wireless communication apparatus and frequency hopping method |
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