CN1210900C - Method for suppressing phase noise by transmission parameter signallings - Google Patents
Method for suppressing phase noise by transmission parameter signallings Download PDFInfo
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Abstract
The present invention relates to a method for suppressing phase noise through making use of TPSs in TDS-OFDM, which belongs to the technical field of digital information transmission. The method of the present invention comprises that inputted digital signals are modulated and mapped after debugged and encoded by inner and outer codes; then, the IDFT treatment can be carried out; guard intervals are inserted on an IDFT time domain block for forming frame bodies; N TPSs are divided into M sets and then are inserted into the frame bodies; each set has one phase reference TPS (the TPS of the intermediate position of each set); the range of the TPS signal is higher than that of other TPS signals; other TPSs form a frequency protective tape for phase reference TPS; frame heads (PN sequence) and the frame bodies with the TPSs are in multiplex connection into signal frames which are transmitted after treated by a channel. The method of the present invention can trace the phase transient change of a received signal in time, suppression phase noise and accurately restore the system synchronization.
Description
Technical field
The invention belongs to digital information transmission technical field, be specifically related to a kind of time-domain synchronization OFDM modulation (Time Domain Synchronous that utilizes, Orthogonal Frequency Division Multiplexing, TDS-OFDM, TDS-OFDM) transmission parameter signaling in (Transmission Parameter Signaling, TPS) method of inhibition phase noise.
Background technology
In the digital communication or broadcast system of synchronous transmission, sent be with sequence x corresponding continuous time of waveform s (t, x), rather than sequence itself.The channel symbol sequence is finished by modulator to the distribution of channel waveform.Except that channel sequence x, waveform also depends on parameter set θ=(θ
T, θ
C).Subclass θ
TBe transmitter parameter, subclass θ
CBe channel parameter, these parameters are unknown for receiver.For recovering symbol sebolic addressing x, receiver must estimate these unknown parameters from received signal.Then, these estimated values will be used as actual value, must set up synchronously, comprise timing information, carrier frequency, sign synchronization etc.
The baseband signal of receiving terminal enters receiver synchronous circuit part, and as shown in Figure 1, synchronous circuit is estimated synchronous parameters such as frequency shift (FS), regularly recovery, phase places according to this baseband signal, obtained carrier wave and recover.The operation that carrier wave recovers mainly comprises following three parts: carry out phase estimation, phase estimation is after matched filter, and it is the execution of carrying out with symbol rate (owing to regularly recovering before the phase bit recovery); The phase place rotation will be multiplied each other through the sampling of data and a plural exp (j θ (nT)) of regularly recovery and matched filtering; Frequency Synchronization, under the situation that has an a certain amount of frequency shift (FS), wide ranges, the thick frequency adjustment of precision are necessary.
Exist to disturb in the Digital Transmission process and noise, wherein phase noise is because the influence of thermal noise and cause the change at random of oscillator phase by the noise that externally fed and control circuit are introduced in the oscillator of sending and receiving end.The phase fluctuation of oscillator and frequency fluctuation have caused the phase noise of carrier wave.Phase noise can both be introduced at transmitting terminal transmitter and receiving terminal tuner etc.
For quadrature amplitude modulation (QAM) modulation, it is circular fuzzy that the constellation point (sampling point) on the I/Q plane appears in these phase jitter meetings, causes intercarrier and intersymbol interference, directly increases bit error rate.
Usually suppressing the most direct method of phase noise is to adopt phase-locked loop (PLL) to come the filtering phase noise.
In receiver, one of method that the reinsertion of carrier is synchronous is to make a start to insert a special pilot signal at frequency domain, and receiver uses a PLL to obtain and follow the tracks of this weight of pilot frequency, and makes the carrier frequency and the Phase synchronization of local oscillator and received signal.
Generally PLL is designed to have narrow bandwidth, but the selection of PLL bandwidth need be compromised between the noise in response speed and the phase estimation value (estimation accuracy) in practice, on the one hand, when there is the phase jitter component in input signal, requirement can not suppress to reflect the component of input phase variation too much, therefore, wish to select the bandwidth of loop enough wide, so that become when following the tracks of receiving phase any in time; On the other hand, a broadband P LL allows more noise to enter loop, thereby worsens phase estimation, and require passband narrow this moment, will get well the noise component(s) inhibition.These two aspects are contradiction to the requirement of PLL bandwidth.Same, settling time and retention time also are contradiction to the requirement of PLL bandwidth synchronously.So the PLL bandwidth that need choose suitable compromise according to actual needs alleviates this contradiction, perhaps take other measure to avoid this contradiction.
Tell about below in ground digital television broadcast and specifically how to do.
Current ground digital TV transmission system in the world mainly contains two kinds of the DVB-T COFDM OFDM of the coding (modulation) in the ASTC 8-VSB (modulation of eight level vestigial side bands) of the U.S. and Europe.
U.S.'s ATSC standard has adopted eight level vestigial side bands (8-VSB) modulating system.ATSC 8VSB pattern can be transmitted the information code check of 19.28Mbps in the 6MHz bandwidth.The input bit rate that is input to transmission system from transfer system is 19.39Mbps, each packet 188Byte, the wherein synchronous and 187Byte information (187/188=19.28/19.39) of 1Byte.Input information at first carries out randomization, carries out the preceding paragraph error correction coding then, and after the additional 20Byte error correcting code, each packet becomes 208Byte, outputs to multiplexer through 2/3 lattice code again, with data segment sync and data fields synchronized mixes.Randomization and forward error correction are not added to the synchronous Byte in the former bag.Synchronous Byte in the bag changes into the segment data synchronizing signal when multiplexing.Two all synthetic at last Frames of data.
8 level symbols and binary data section vestigial sideband amplitudemodulation synchronous and field synchronization employing suppressed carrier is modulated.VSB allows a sideband all pass through, and another sideband only residual a part of train.The root mean square of respectively having arranged to be shaped as normalizing in the sideband both sides rises the transition region of surplus profound response stroke 310KHz, and the baseband signal of generation converts analog form (D/A converter) to, is modulated to intermediate frequency carrier then, and generates the intermediate-freuqncy signal of residual sideband.Normalized transmission frequency spectrum such as Fig. 2 in the 6MHz bandwidth.
Can see in Fig. 2 that at 310KHz place, low side border a little pilot signal is arranged, this pilot signal is used for carrier lock in vsb receiver, and pilot signal power makes gross power increase 0.3dB, helps to reduce the loss in the enforcement.And, NTSC is not produced co-channel interference because pilot signal is positioned at the residual sideband zone of co-channel NTSC signal.
The ATSC carrier wave recovers to finish on pilot tone shown in Figure 2 with the PLL circuit.The loop bandwidth of its PLL is enough wide, can provide ± the wide frequency of 100kHz is introduced scope, and the phase noise of following the tracks of about 2kHz on the filtered signal.But being too narrow to again, the PLL bandwidth is enough to suppress effectively strong white noise and the co-channel interference signal of NTSC.
The ASTC section synchronously and symbol clock recovery also be employing PLL circuit.
When but ATSC existed near strong multipath to change (phase place), above-mentioned single little pilot signal can be had a strong impact on, and carrier wave recovers the difficulty that becomes.
Europe DVB-T system adopts the modulation technique COFDM (Coded Orthogonal Frequency Division Multiplexing (COFDM)) different with U.S. 8-VSB.OFDM belongs to multi-carrier modulation technology, and it is divided into transmitted bit on the low bit rate subcarrier of thousands of meters, and each subchannel is the arrowband flat channel.
The data frame structure of DVB-T is formed a Frame to 4 OFDM symbolic frames, and each OFDM symbolic frame comprises 68 OFDM symbols.The carrier number of an OFDM symbol is constant, and 1705 carrier waves are arranged under the 2K pattern, and subcarrier spacing is 4.46KHz, and the effective information carrier number is 1512 carrier waves; 6817 carrier waves are arranged under the 8K pattern, and subcarrier spacing is 1.11KHz, and the effective information carrier number is 6048 carrier waves.In an OFDM Frame, use QPSK, 16QAM or the 64QAM modulation of the same Gray code mapping on all carrier waves.Each V bit symbol of exporting from interleaver is mapped to a constellation point in the modulation constellation.
One of the implication of " coding " among the Coded Orthogonal Frequency Division Multiplexing (COFDM) COFDM is meant in-OFDM frequency spectrum has inserted some " pilot tone " signals, here so-called " pilot tone " is meant the carrier wave of some OFDM like this, they are by the known data-modulated of receiver, what they transmitted is not modulating data itself, because it is known that these data receivers are systems, the purpose that pilot tone is set is that system transmits the parameter of some transmitter or the characteristic of test channel by the data on the pilot tone.
The effect of pilot tone in COFDM is very important, and its use comprises that frame synchronization, Frequency Synchronization, time synchronized, channel transfer characteristic are estimated, transmission mode is discerned and follows the tracks of phase noise etc.The data of modulated pilots are the pseudo random sequences that generates from a pseudo-random sequence generator of stipulating in advance.Stipulated scattered pilot, continuous pilot and transmission parameter signaling (TPS) pilot tone among the DVB-T.
Scattered pilot is as the valuation of the characteristic of channel; Continuous pilot is synchronous as timing and carrier frequency.Their amplitude is than data subcarrier height+2.5dB.The position of continuous pilot in each COFDM symbol all fixed, and inserted 177 continuous pilot in the 8k pattern, inserted 45 continuous pilot in the 2k pattern.The position of scattering pilot tone is different in different COFDM symbols, but with four COFDM symbols is loop cycle, as shown in Figure 3, white circle representative data subcarrier wherein, gray circles is represented the scattered pilot subcarrier, black circles is represented the TPS pilot sub-carrier, and the oblique line circle is represented the continuous pilot subcarrier.
The TPS carrier wave of DVB-T is used for transmission system parameters, i.e. chnnel coding and modulation parameter.Each OFDM symbol contains 1 TPS bit, in the OFDM symbolic frame 68/17bit is arranged, and the fixed position is arranged, as shown in Figure 3 in planisphere.The TPS carrier wave adopts the DBPSK modulation.
Because subcarrier spacing is very little, therefore, OFDM multicarrier system is more responsive to phase noise than single-carrier system.The influence of phase noise can be modeled as two parts: (1) public part, it causes the phase place rotation of the data symbol that all receive in the present frame, cause the integral body rotation of signal constellation (in digital modulation), it is the monotonically decreasing function of sub-carrier number N, as N=1 when (being equivalent to single-carrier system), reach maximum, when N was tending towards infinite, this part also was tending towards 0; (2) disperse part, it is similar to white Gaussian noise, will cause defocusing of corresponding received signal constellation point, and this part is the dull increasing function of sub-carrier number N, as N=1 when (being equivalent to single-carrier system), reaches minimum.
First's phase noise suppresses by the continuous pilot signal that PLL follows the tracks of among the DVB-T easily.But for the second portion phase noise, DVB-T compensates difficulty, and promptly DVB-T is bad to random phase Noise Suppression performance, can not in time reflect the variation of phase of received signal.
In recent years Tsing-Hua University also proposed " the ground digital multimedia TV broad cast host-host protocol (and Terrestrial DigitalMultimedia-Television Broadcasting; DMB-T) ", time-domain synchronization OFDM (TimeDomain Synchronous Orthogonal-Frequency-Division-Multiplex, TDS-OFDM) modulation technique have been adopted.(number of patent application: 00123597.4 " ground digital multimedia TV broad cast system " and number of patent application: 01124144.6 " protection fill method at interval in the orthogonal FDM modulation system ").
The structure of DMB-T system has the frame structure of layering; the PN sequence is as synchronously; variable guard intervals (filling PN sequence, Cyclic Prefix or null value); length is no more than 1/4 of IDFT block length; be the cyclical transmission scheme of consecutive days circulation timei, has unique frame address, and the support time is shared multiple access; support continuously and the bursty data mixed transport, and MpEG sign indicating number bag and second time are synchronous.
The physical channel frame structure of DMB-T host-host protocol as shown in Figure 4, it is classification.A basic frame is called signal frame.Signal frame is made up of two parts, i.e. frame synchronization and frame.The frame group is defined as a group signal frame, and its first frame definition is a frame group head (control frame).Superframe is defined as a framing group.The top layer of frame structure be called a day frame (Calendar DayFrame, CDF).Physical channel is the cycle, and and Absolute Time Synchronization.
Signal frame is the elementary cell of DMB-T system frame structure.A signal frame is formed (see figure 4) by frame synchronization and frame two parts.The baseband signalling rate of frame synchronization and frame is identical, is defined as 7.56MSps.
The PN sequence of base band frame synchronizing signal has 420 symbols.Unlike signal frame among the signal frame group has different frame synchronizing signals.So frame synchronization can be used for identification as the frame synchronization feature of signal specific frame.
The PN sequence definition is one 8 rank m sequence, and its proper polynomial is defined as X
8+ X
6+ x
5+ x+1, the initial condition template will be determined the phase place of the m sequence that generates.For a specific signal frame, the initial condition of its signal frame number decision PN sequence.After " 0 " was arrived "+1 " value and " 1 " and arrive the mapping that " 1 " be worth, the PN sequence transformation was the binary signal of non-return-to-zero.
The baseband signal of a frame is an OFDM (OFDM) piece.OFDM piece further is divided into protection leaf inverse transformation (IDFT) piece at interval and in discrete answering.For TDS-OFDM, the PN synchronizing sequence is both as frame synchronization, and again as the protection of OFDM at interval, and frame is as the DFT piece, as shown in Figure 4.
The DFT piece has 3780 symbols (subcarrier) and continues 500us, and adjacent sub-carrier is spaced apart 2KHz, and each sub-carrier adopts QPSK, 16QAM and even or non-homogeneous 64QAM mapping.
Because the OTDM of PN sequence and DFT piece, and the PN sequence is known array for receiving terminal, and therefore, PN sequence and DFT piece are can be separated at receiving terminal.The signal frame of receiving terminal can be regarded as the OFDM with zero padding protection interval after removing the PN sequence, is of equal value and have zero padding protection OFDM at interval in theory with the OFDM with Cyclic Prefix protection interval.
In a frame, 3780 symbols (carrier wave) are arranged, wherein 36 subcarriers are used to carry transmission parameter signaling (Transmission Parameter Signaling, TPS), remaining 3744 subcarriers are used for the payload user data transmission.Data-signal is that the TPS signal defines in time domain in frequency domain definition, and with data-signal at the frequency domain quadrature, as shown in Figure 5.TPS repeats in each signal frame in the frame group.Transmission mode only could change when a new frame group begins.
In DMB-T, the PN synchronizing sequence be used for frame synchronization, Frequency Synchronization, regularly synchronously, channel estimating and equilibrium, transmission frame identification and follow the tracks of phase noise etc.
Also there is phase noise in the receiving terminal of the DMB-T system that proposes in Tsing-Hua University, need take certain measure to suppress phase noise, recovers so that obtain reliable carrier wave.
Summary of the invention
The objective of the invention is the phase noise problem that exists in the digital communication system at multi-carrier modulation, modulate the method that (TDS-OFDM) middle transmission parameter signaling (TPS) suppresses phase noise and propose a kind of time-domain synchronization OFDM that utilizes, in time follow the tracks of the transient change of phase of received signal, improved the net synchronization capability of system.
The present invention proposes the method that transmission parameter signaling (TPS) suppresses phase noise, it is characterized in that, may further comprise the steps making a start:
1) after the inside and outside sign indicating number of the digital signal process error correction coding with input, modulates mapping;
2) symbol after will shining upon carries out inverse discrete Fourier transformer inverse-discrete (IDFT) and handles, and protection is inserted IDFT time domain piece at interval and formed frame;
3) N TPS is divided into the M group and is inserted in the frame, wherein N, M are positive integer;
4) a phase reference TPS who is used for the phase noise reference is arranged in every group of TPS, other TPS signal during its amplitude is higher than on the same group, other TPS constitutes the frequency protection band of phase reference TPS;
5) the frame multiple connection with frame head and the above-mentioned TPS of carrying becomes signal frame, through giving Channel Transmission after the processing such as digital to analog conversion, shaping filter, radio frequency up conversion, carries out the respective phase noise suppressed by receiving end; The method that described phase noise suppresses can be: the signal of receiving at first carries out bandpass filtering treatment to M group phase reference TPS subcarrier, and relatively M output result gets wherein maximum that filtering result and estimate as the phase noise of received signal.
The position of described phase reference TPS preferably is positioned at every group centre.
Described N may be selected to be 36.
Described M may be selected to be 4.
The bandwidth of described bandpass filtering treatment can be
Wherein Δ f is the OFDM subcarrier spacing.
Described M can be 4.
Characteristics of the present invention:
The present invention is according to the characteristic of OFDM multicarrier modulation system phase noise, a kind of method of utilizing transmission parameter signaling (TPS) inhibition phase noise in the time-domain synchronization OFDM modulation (TDS-OFDM) has specifically been proposed, thereby in time lock the transient change of phase of received signal, accurately recovery system is synchronous.
Description of drawings
Fig. 1 is a typical digital receiver synchronous circuit block diagram.
Fig. 2 is the position of pilot tone in channel spectrum among the U.S. ATSC.
Fig. 3 is the locus of pilot tone among the European DVB-T.
Fig. 4 is the hierarchical frame structure of the DMB-T host-host protocol of the present invention's employing.
The embedding block diagram of Fig. 5 TPS subcarrier of the present invention in TDS-OFDM.
Fig. 6 is the distribution of TPS subcarrier in TDS-OFDM among the present invention.
Fig. 7 is the relation of normalization NMSE and the boundary belt and the filter bandwidht of the reinsertion of carrier.
Fig. 8 estimates for TPS among the present invention extracts phase noise by filtering.
Fig. 9 is for adopting ground digital multimedia TV broad cast system emission principle block diagram of the present invention.
Figure 10 receives theory diagram for adopting ground digital multimedia TV broad cast system of the present invention.
Embodiment
Below in conjunction with accompanying drawing specific embodiments of the invention are described in detail.
It is as follows that the method that a kind of TPS of utilization that the present invention proposes suppresses phase noise is used for the performing step of the embodiment that the TDS-OFDM modulating system makes a start:
1) digital signal of input is carried out ISN, outer sign indicating number error correction coding and interweave;
2) signal after the error correction coding is carried out QPSK or mQAM sign map;
3) symbol after will shining upon carries out IDFT and handles;
4) will protect the interval to insert IDFT time domain piece and form frame;
5) 36 TPS being divided into 4 groups is inserted in the frame;
6) make the amplitude of phase reference TPS (TPS in every group of centre position) be higher than other TPS signal;
7) the frame multiple connection with frame head (PN sequence) and the above-mentioned TPS of carrying becomes signal frame;
8) give Channel Transmission after at last the signal after the multiple connection being formed processing such as filtering, up conversion.
The TDS-OFDM modulating system also belongs to the OFDM technology, and therefore, the phase noise of TDS-OFDM system comprises public rotating part and external dispersion part.Public rotating part is followed the tracks of by the PN synchronizing sequence of DMB-T signal frame; And for the random phase noise that external dispersion partly produces, the present invention proposes and utilize that the TPS subcarrier suppresses among the TDS-OFDM, so that become when in time reflecting phase of received signal any instantaneous.
Utilize transmission parameter signaling (TPS) suppress TPS among the embodiment of method of phase noise be inserted in the OFDM frame the position as shown in Figure 6,36 TPS subcarriers are divided into 4 groups, equally spaced insert in the DFT piece.Every group comprises 9 subcarriers, and wherein the power of the 5th subcarrier (we are referred to as phase reference TPS) is higher than other 8 subcarriers, is used for the estimation and the compensation of random phase noise.The frequency protection band that 4 subcarrier spacings are respectively arranged on the both sides of phase reference TPS to extract main phase noise as far as possible, reduces data simultaneously and disturbs.Frequency protection selection at interval depends on the shape of phase noise template.
At receiving terminal, can finish carrier wave with the band pass filter that a centre frequency is positioned at phase reference TPS place and recover, therefore, except that the phase reference TPS that knows clearly must have the boundary belt, the bandwidth of filter also is an important parameter.Theory analysis shows that the normalization mean square error (NMSE) of the reinsertion of carrier is relevant with the bandwidth that the frequency protection band bandwidth of phase reference TPS and carrier wave recover filter, wherein is that normalization is carried out in reference with the subcarrier spacing, as shown in Figure 7.
In the present embodiment; in the frame of TDS-OFDM signal frame, insert 4 groups of TPS subcarriers; each group comprises 1 TPS (phase reference TPS that is used to suppress phase noise; be positioned at every group centre position); its transmitting power is higher than other TPS signal; and the subcarrier spacing of the frequency protection band on its both sides is counted M and is got 4, and promptly frequency protection band bandwidth is BW
Guard=M * Δ f=4 * 2kHz=8kHz, wherein Δ f is the OFDM subcarrier spacing.
In the present embodiment, carrier wave recovers the bandwidth BW of filter
Filter〉=[BW
Guard]/2, getting the band pass filter bandwidth in the present embodiment is 2 subcarrier spacings, i.e. 4kHz.
At receiving terminal, one of method of utilizing above-mentioned TPS inhibition phase noise is: the signal of receiving at first carries out bandpass filtering treatment to 4 groups of phase reference TPS subcarriers, relatively export results for 4, get wherein maximum that filtering result and estimate TPS as shown in Figure 8 as the phase noise of received signal
R3Obtain after the phase noise estimation, baseband signal multiply by the complex conjugate of the phase noise vector of estimation, obtain the baseband signal of phase compensation, carrying out channel frequency response based on the PN synchronizing sequence among the TDS-OFDM then estimates, the estimated channel response is used for the signal frame after the balanced phase compensation, through forming baseband signal behind the automatic gain control AGC, give the processing section of back at last, recover the data of making a start and transmitting.
Described Fig. 3 can see from the previous technique background, a large amount of pilot signal (comprising the TPS signal) has been placed by Europe DVB-T system in the OFDM symbol, but the frequency protection band is not left on the both sides of DVB-T system pilot, the both sides of each pilot tone all are actual data-signals, from above-mentioned analysis as can be known, DVB-T will adopt method of the present invention, and the one, need filter bandwidht very narrow and precipitous, realize complexity, data also can exist as disturbing; The 2nd, even realized filtering, but there is not the frequency protection band, from above-mentioned Fig. 7 as can be known, the phase noise rejection is also bad.
The ground digital multimedia TV broad cast emission system principle composition frame chart of a described method of employing present embodiment as shown in Figure 9.The MPEG TS code stream of input can be multimedia messagess such as video, audio frequency, figure, data; in order to resist the error code that produces in the transmission course; TS stream is at first through after ISN, outer sign indicating number and the error correction coding such as interweave; carry out QPSK or mQAM sign map and IDFT then and handle, will protect and insert IDFT time domain piece formation frame at interval.36 TPS are divided into 4 groups are inserted in the frame, make the signal amplitude of phase reference TPS (TPS in every group of centre position) be higher than other TPS signal.The frame multiple connection of frame head (PN sequence) and the above-mentioned TPS of carrying is become signal frame, at last with the process of the signal after multiple connection D/A converter module, be converted to suitable analog signal, the radio frequency module receives this analog signal, and the result after the processing gives transmitting antenna or other signal transmitter.
The ground digital multimedia TV broad cast receiving system principle composition frame chart of a described method of employing present embodiment as shown in figure 10.Antenna or other signal receiver receive modulation signal, give after down conversion module carries out frequency translation, give analog-to-digital conversion and become digital signal, utilize the time domain PN synchronizing sequence reinsertion of carrier synchronously, sign synchronization, regularly synchronous etc., and adopt TPS of the present invention further to suppress and the tracking phase noise, after separating the processing of mediation error correction decode method through the OFDM multicarrier then, recover MPEG TS code stream at last.
The Computer Simulation that the ground digital multimedia TV broad cast receiving system of above-mentioned employing the method for the invention is carried out is tested, on the basis of computer artificial result, realized adopting the function model machine of the ground digital multimedia TV broad cast receiving system of the method for the invention with FPGA.
In conjunction with the accompanying drawings specific embodiments of the invention are had been described in detail above, but the present invention is not restricted to the foregoing description, under the spirit and scope situation of the claim that does not break away from the application, those skilled in the art can make various modifications or remodeling.
Claims (6)
1, a kind of method of utilizing transmission parameter signaling (TPS) to suppress phase noise is characterized in that, may further comprise the steps making a start:
1) after the inside and outside sign indicating number of the digital signal process error correction coding with input, modulates mapping;
2) symbol after will shining upon carries out inverse discrete Fourier transformer inverse-discrete (IDFT) and handles, and protection is inserted IDFT time domain piece at interval and formed frame;
3) N TPS is divided into the M group and is inserted in the frame, wherein N, M are positive integer:
4) a phase reference TPS who is used for the phase noise reference is arranged in every group of TPS, other TPS signal during its amplitude is higher than on the same group, other TPS constitutes the frequency protection band of phase reference TPS:
5) the frame multiple connection with frame head and the above-mentioned TPS of carrying becomes signal frame, through giving Channel Transmission after the processing such as digital to analog conversion, shaping filter, radio frequency up conversion, carry out the respective phase noise suppressed by receiving end: the method that described phase noise suppresses is: the signal of receiving at first carries out bandpass filtering treatment to M group phase reference TPS subcarrier, relatively M output result gets wherein maximum that filtering result and estimates as the phase noise of received signal.
2, the method for utilizing transmission parameter signaling (TPS) to suppress phase noise as claimed in claim 1, it is characterized in that: the position of described phase reference TPS is positioned at every group centre.
3, the method for utilizing transmission parameter signaling (TPS) to suppress phase noise as claimed in claim 1, it is characterized in that: described N is 36.
4, the method for utilizing transmission parameter signaling (TPS) to suppress phase noise as claimed in claim 1, it is characterized in that: described M is 4.
5, the method for utilizing transmission parameter signaling (TPS) to suppress phase noise as claimed in claim 1, it is characterized in that: the bandwidth of described bandpass filtering treatment is
Wherein Δ f is the OFDM subcarrier spacing.
6, the method for utilizing transmission parameter signaling (TPS) to suppress phase noise as claimed in claim 5, it is characterized in that: described M is 4.
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| CN100347962C (en) * | 2004-03-31 | 2007-11-07 | 清华大学 | Method for removing phase noise for time domain synchronous or thogonal frequency-division multiplex receiver and system and thereof |
| KR100820824B1 (en) * | 2006-03-02 | 2008-04-10 | 엘지전자 주식회사 | Method and apparatus for digital automatic gain control |
| KR20080001940A (en) * | 2006-06-30 | 2008-01-04 | 엘지전자 주식회사 | Apparatus for receiving braodcasting signals and method thereof |
| CN101102609B (en) * | 2007-08-10 | 2013-08-07 | 中兴通讯股份有限公司 | Information mapping method and device and information recovery method and device |
| CN101465714B (en) * | 2008-12-10 | 2010-10-27 | 华为技术有限公司 | Method, device and system for mixed multiple connection and de-multiple connection |
| CN101505292B (en) * | 2009-02-27 | 2011-06-29 | 清华大学 | Phase noise correcting method suitable for MIMO-OFDM pre-coding |
| CN101848181B (en) * | 2009-03-25 | 2012-12-12 | 清华大学 | Digital signal sending method based on time-frequency domain conversation |
| JP2020507986A (en) * | 2017-02-03 | 2020-03-12 | エルジー エレクトロニクス インコーポレイティド | Method and apparatus for estimating phase noise in a wireless communication system |
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