CN106685877A - Processing method of received signals of receiving end - Google Patents

Processing method of received signals of receiving end Download PDF

Info

Publication number
CN106685877A
CN106685877A CN201611013351.1A CN201611013351A CN106685877A CN 106685877 A CN106685877 A CN 106685877A CN 201611013351 A CN201611013351 A CN 201611013351A CN 106685877 A CN106685877 A CN 106685877A
Authority
CN
China
Prior art keywords
sequence
frequency domain
time domain
fixed sequence
channel estimation
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.)
Withdrawn
Application number
CN201611013351.1A
Other languages
Chinese (zh)
Inventor
张文军
黄戈
管云峰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai National Engineering Research Center of Digital Television Co Ltd
Original Assignee
Shanghai National Engineering Research Center of Digital Television Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai National Engineering Research Center of Digital Television Co Ltd filed Critical Shanghai National Engineering Research Center of Digital Television Co Ltd
Priority to CN201611013351.1A priority Critical patent/CN106685877A/en
Publication of CN106685877A publication Critical patent/CN106685877A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2602Signal structure
    • H04L27/261Details of reference signals
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2602Signal structure
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00Baseband systems
    • H04L25/02Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/03Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
    • H04L25/03006Arrangements for removing intersymbol interference
    • H04L25/03012Arrangements for removing intersymbol interference operating in the time domain
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2626Arrangements specific to the transmitter only
    • H04L27/2627Modulators

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

The present invention discloses a processing method of the received signals of a receiving end. The processing method is characterized by including the following steps that: received, demodulated and delayed signals are correlated with the received signals, so that a coarse synchronization position can be obtained; fast Fourier transformation is performed on a correlation value, so that frequency domain signals can be obtained, the shift points of the frequency domain signals are divided by a fixed sequence, so that the channel estimation values of fixed sequence points can be obtained; inverse Fourier transformation is performed on the channel estimation values, so that time domain signals can be obtained, when an obvious peak appears, a shift number is correct integer frequency offset, and at the same time, the value of the peak indicates a strongest diameter position; after integer frequency offset is compensated in the time domain, the compensated integer frequency offset is locally correlated with a time domain sequence corresponding to the fixed sequence in the frequency domain, so that fractional part of frequency offset is calculated, and a quasi timing synchronization position can be obtained; and interpolation is performed through using the channel estimation values of the fixed sequence points in the frequency domain, so that the channel estimation value of a signal sequence can be obtained, and then, coherent demodulation is performed, so that signals can be obtained. With the processing method of the received signals of the receiving end adopted, the problem of failure probability in the detection of a low-complexity receiving algorithm under a condition that preamble symbols are in a frequency selective fading channel can be solved.

Description

Method for processing receiving signal of receiving end
Technical Field
The present invention relates to the field of wireless broadcast communication technologies, and in particular, to a method for generating preamble symbols in a physical frame and a method for generating frequency domain OFDM symbols.
Background
Generally, in order for a receiving end of an OFDM system to correctly demodulate data transmitted by a transmitting end, the OFDM system must implement accurate and reliable time synchronization between the transmitting end and the receiving end. Meanwhile, since the OFDM system is very sensitive to the carrier frequency offset, the receiving end of the OFDM system needs to provide an accurate and efficient carrier frequency spectrum estimation method to accurately estimate and correct the carrier frequency offset.
At present, a method for implementing time synchronization between a transmitting end and a receiving end in an OFDM system is basically implemented based on preamble symbols. The preamble symbol is a symbol sequence known to both the transmitting end and the receiving end of the OFDM system, and serves as the start of a physical frame (named P1 symbol), and the P1 symbol appears only once in each physical frame, and marks the start of the physical frame. The P1 symbols have the following uses:
1) enabling a receiving end to quickly detect whether a signal transmitted in a channel is an expected received signal;
2) providing basic transmission parameters (such as FFT point number, frame type information and the like) so that a receiving end can perform subsequent receiving processing;
3) and detecting initial carrier frequency offset and timing error, and compensating to achieve frequency and timing synchronization.
The DVB _ T2 standard provides a P1 symbol design based on a CAB time domain structure, and the functions are well realized. However, there are still some limitations on low complexity reception algorithms. For example, in a long multipath channel with 1024, 542, or 482 symbols, a large deviation occurs in timing coarse synchronization using the CAB structure, which results in an error in estimating the carrier integer multiple frequency offset in the frequency domain. In addition, DPSK differential decoding may also fail in frequency selective fading channels.
Disclosure of Invention
The invention solves the problem that the detection of preamble symbols in a low-complexity receiving algorithm under a frequency selective fading channel has failure probability in the current DVB _ T2 standard and other standards.
In order to solve the above problem, an embodiment of the present invention provides a method for generating a preamble symbol in a physical frame, including the following steps: respectively generating a fixed sequence and a signaling sequence on a frequency domain; filling the fixed sequence and the signaling sequence onto effective subcarriers, wherein the fixed sequence and the signaling sequence are arranged in a parity staggered manner; filling zero sequence subcarriers on two sides of the effective subcarriers respectively to form frequency domain OFDM symbols with preset length; performing inverse discrete Fourier transform on the frequency domain OFDM symbol to obtain a time domain OFDM symbol; generating a modulation signal of the time domain OFDM symbol; and generating a preamble symbol based on the time domain OFDM symbol and the modulation signal.
Optionally, the length of the fixed sequence is equal to the length of the signaling sequence, and the length is smaller than 1/2 of the predetermined length.
Optionally, the filling zero sequence subcarriers at two sides of the effective subcarrier to form a frequency domain OFDM symbol with a predetermined length respectively includes: and filling zero sequence subcarriers with equal length on two sides of the effective subcarriers respectively to form frequency domain OFDM symbols with preset length.
Optionally, the length of the zero sequence sub-carrier padded on each side is greater than a critical length value, and the critical length value is determined by the systematic symbol rate and a predetermined length.
Optionally, the generating the modulation signal of the time domain OFDM symbol includes: setting a frequency shift sequence; and multiplying the time domain OFDM symbol by the frequency shift sequence to obtain a modulation signal of the time domain OFDM symbol.
Optionally, the length of the frequency shift sequence is equal to or less than the length of the time domain OFDM symbol.
Optionally, generating a preamble symbol based on the time domain OFDM symbol and the modulation signal refers to: and taking the modulation signal as a guard interval of the time domain OFDM symbol, and splicing the guard interval at the front part of the time domain OFDM symbol to generate a preamble symbol.
Optionally, the predetermined length is 1024.
Optionally, the fixed sequence is a pseudo-random binary sequence.
Optionally, the step of generating a fixed sequence and a signaling sequence in the frequency domain, and the step of filling the fixed sequence and the signaling sequence into the effective subcarriers, and further includes the following steps between the fixed sequence and the signaling sequence in a parity-even staggered arrangement: and respectively carrying out DBPSK mapping on the fixed sequence and the signaling sequence to obtain the mapped fixed sequence and the mapped signaling sequence.
The embodiment of the invention also provides a method for generating the frequency domain OFDM symbol, which comprises the following steps: respectively generating a fixed sequence and a signaling sequence on a frequency domain; filling the fixed sequence and the signaling sequence onto effective subcarriers, wherein the fixed sequence and the signaling sequence are arranged in a parity staggered manner; and filling zero sequence subcarriers on two sides of the effective subcarriers respectively to form frequency domain OFDM symbols with preset length.
Compared with the prior art, the technical scheme of the invention has the following beneficial effects:
the structure of the modulation signal of the time domain OFDM symbol and the time domain OFDM symbol (as a preamble symbol) ensures that an obvious peak value can be obtained by utilizing delay correlation at a receiving end. Further, in the process of generating the preamble symbol, designing the modulation signal of the time domain OFDM symbol can avoid that the receiving end is subjected to continuous wave interference or single frequency interference, or a multipath channel with the same length as the modulation signal occurs, or a false detection peak occurs when the guard interval length in the received signal is the same as the length of the modulation signal.
Drawings
Fig. 1 is a flowchart illustrating a method for generating preamble symbols in a physical frame according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of the generation of a fixed sequence using a pseudo-random binary sequence generator in accordance with the present invention;
fig. 3 is a schematic diagram of frequency domain carrier distribution of frequency domain OFDM symbols generated in the method for generating preamble symbols in physical frames according to the present invention.
Detailed Description
The inventor finds that in the current DVB _ T2 standard and other standards, preamble symbols have a problem of a probability of failure in detection by a low-complexity reception algorithm under a frequency selective fading channel.
In view of the above problems, the inventors have studied and provided a method for generating preamble symbols in a physical frame, which ensures that a receiving end can still process a received signal with a carrier frequency deviation within a range of-500 kHz to 500 kHz.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
Fig. 1 is a flowchart illustrating a method for generating preamble symbols in a physical frame according to an embodiment of the present invention. Referring to fig. 1, a method for generating preamble symbols in a physical frame includes the steps of:
step S11: respectively generating a fixed sequence and a signaling sequence on a frequency domain;
step S12: filling a fixed sequence and a signaling sequence onto effective subcarriers, wherein the fixed sequence and the signaling sequence are arranged in a parity staggered manner;
step S13: filling zero sequence subcarriers on two sides of the effective subcarriers respectively to form frequency domain OFDM symbols with preset length;
step S14: performing inverse discrete Fourier transform on the frequency domain OFDM symbol to obtain a time domain OFDM symbol;
step S15: generating a modulation signal of the time domain OFDM symbol;
step S16: and generating a preamble symbol based on the time domain OFDM symbol and the modulation signal.
It should be noted that the preamble symbol can be described from two domains, i.e., a time domain and a frequency domain. In this embodiment, the preamble symbol is generated by generating a frequency domain OFDM symbol in the frequency domain, and generating a preamble symbol in the time domain based on a modulation signal of the frequency domain OFDM symbol and a corresponding time domain OFDM symbol.
Specifically, as described in step S11, the fixed sequence and the signaling sequence are generated in the frequency domain, respectively. The fixed sequence includes the relevant information that the receiving end can use to do carrier frequency synchronization and timing synchronization, and the signaling sequence includes each basic transmission parameter.
In this embodiment, the fixed sequence may be a pseudo-random binary sequence.
For example, let fixed sequence be FC0,FC1,…,FCN-2The pseudo random binary sequence generator (PRBS) can be used for generating, and the specific generation process is as shown in fig. 2, which uses the pseudo random binary sequence generator to generate a schematic diagram of a fixed sequence. In practical applications, other types of sequences may be selected for the fixed sequence.
The signaling sequence is used to transmit P bits of information (e.g., various signaling), and has a total of 2PEach possibility is mapped to a signalling sequence of length M. The sequence group has 2PThe sequences are not related to each other, and are not related to known fixed sequences.
In other embodiments, DBPSK mapping may be performed on the fixed sequence and the signaling sequence according to system requirements.
In particular, for fixed sequencesPerforming DBPSK mapping to FC0,FC1,…,FCN-2Is mapped intoThe formula is as follows:
for the signaling sequence (set to SC)0,SC1,…,SCM-2) Performing DBPSK mapping to SC0,SC1,…,SCM-2Is mapped asThe formula is as follows:
the fixed sequence and the signaling sequence are padded on the active subcarriers and are arranged in a parity staggered manner as described in step S12.
In a preferred embodiment, the length of the fixed sequence is equal to the length of the signaling sequence, and the length is less than 1/2 of the predetermined length. The predetermined length is 1024, but it can be changed according to the system requirement in practical application.
Taking the predetermined length as 1024 as an example, let the length of the fixed sequence be N (that is, the number of the effective subcarriers carrying the fixed sequence be N), and the length of the signaling sequence be M (that is, the number of the effective subcarriers carrying the signaling sequence be M), where M is equal to N in this embodiment. In other embodiments, N may also be slightly larger than M.
The fixed sequence and the signaling sequence are arranged in a parity staggered manner, namely the fixed sequence is filled to the position of even subcarrier (or odd subcarrier), correspondingly, the signaling sequence is filled to the position of odd subcarrier (or even subcarrier), thereby the distribution state of the parity staggered arrangement of the fixed sequence and the signaling sequence is presented on the effective subcarrier of the frequency domain. It should be noted that, when the lengths of the fixed sequence and the signaling sequence are not consistent (for example, M > N), the parity interleaving of the fixed sequence and the signaling sequence may be implemented by means of zero padding sequence subcarriers.
Zero sequence subcarriers are padded on both sides of the effective subcarrier to form frequency domain OFDM symbols of a predetermined length, respectively, as described in step S13.
In a preferred embodiment, this step comprises: and filling zero sequence subcarriers with equal length on two sides of the effective subcarriers respectively to form frequency domain OFDM symbols with preset length.
Following the example of a predetermined length of 1024, the length G of the zero-sequence subcarrier is 1024-M-N, and (1024-M-N)/2 zero-sequence subcarriers are padded on both sides.
Further, in order to ensure that the receiving end can still process the received signal within the carrier frequency deviation range of-500 kHz to 500kHz, the value of (1024-M-N)/2 is usually larger than the critical length value (set to TH), which is determined by the systematic symbol rate and the predetermined length. E.g., a systematic symbol rate of 1024, 7.56M, length, thenFor example, when M is 350, G is 324, and each side is padded with 162 zero-sequence subcarriers.
Accordingly, subcarriers (i.e., frequency domain OFDM symbols) P1_ X of a predetermined length (1024) are provided0,P1_X1,…,P1_X1023Generated by filling in the following way:
wherein,the parity positions may be interchanged.
Fig. 3 is a schematic diagram illustrating a frequency domain carrier distribution of frequency domain OFDM symbols generated by the method for generating preamble symbols in a physical frame according to the present invention.
As shown in step S14, the frequency domain OFDM symbol is inverse discrete fourier transformed to obtain a time domain OFDM symbol.
The inverse discrete fourier transform described in this step is a common way of converting a frequency domain signal into a time domain signal, and is not described herein again.
P1_XiObtaining a time domain OFDM symbol after performing inverse discrete Fourier transform:
a modulated signal of the time domain OFDM symbol is generated as described in step S15.
Specifically, the method comprises the following steps: 1) setting a frequency shift sequence; 2) and multiplying the time domain OFDM symbol by the frequency shift sequence to obtain a modulation signal of the time domain OFDM symbol.
For example, let the frequency shift sequence beWherein f isSH1/(1024T). M (t) can also be designed into other sequences, such as m-sequence or some simplified window sequence.
The modulation signal of the time domain OFDM symbol is P1_ b (t), and P1_ b (t) is obtained by multiplying P1_ a (t) by the frequency shift sequence m (t) (i.e., P1_ b (t) ═ P1_ a (t) × m (t)), and is used as the guard interval of P1_ a (t).
A preamble symbol is generated based on the time domain OFDM symbol and the modulation signal as described in step S16.
Specifically, the method comprises the following steps: and taking the modulation signal as a guard interval of the time domain OFDM symbol, and splicing the guard interval at the front part of the time domain OFDM symbol to generate a preamble symbol.
For example, the preamble symbol may be generated according to the following formula:
the length of the guard interval may also be smaller than the length of the time domain OFDM symbol, the length of the guard interval is set to be B _ len, the length of the time domain OFDM symbol is set to be a, and the front B _ len part of a is taken for modulation, that is:
the embodiment of the invention also provides a method for processing the receiving signal of the receiving end. The method comprises the following specific steps:
step S21: receiving a signal, which is r (t).
Step S22: demodulating the received signal by M (t); for example,fSHmultiplying the received signal by 1/(1024T)Then, order
Step S23: will demodulateDelaying the latter signal; for example, let r2(t)=r1(t-1024)。
Step S24: correlating the delayed signal with the received signal (i.e., r)2(t) correlates with r (t) to obtain a correlation value (i.e., the location where the timing coarse synchronization is obtained).
Step S25: and performing Fast Fourier Transform (FFT) on the correlation value to obtain a frequency domain 1K signal, and removing the fixed sequence from the signal frequency domain shift point to obtain a channel estimation value of the fixed sequence point.
Step S26: and performing inverse Fourier transform (IFFT) on the channel estimation value to a time domain, wherein if an obvious peak value exists, the shift number is correct integer frequency offset, and the peak value also marks the position of the strongest path.
Step S27: after the time domain compensates the integral multiple frequency offset, the time domain sequence corresponding to the fixed sequence on the frequency domain is utilized to carry out local correlation, thereby calculating the decimal frequency offset and obtaining the accurate timing synchronization position.
Step S28: and interpolating a channel estimation value of the signaling sequence by utilizing the channel estimation value of the fixed sequence point in a frequency domain, and then carrying out coherent demodulation to obtain the signaling.
The embodiment of the invention also provides a method for generating the frequency domain OFDM symbol, which comprises the following steps:
step S31: respectively generating a fixed sequence and a signaling sequence on a frequency domain;
step S32: filling a fixed sequence and a signaling sequence onto effective subcarriers, wherein the fixed sequence and the signaling sequence are arranged in a parity staggered manner;
step S33: and filling zero sequence subcarriers on two sides of the effective subcarriers respectively to form frequency domain OFDM symbols with preset length.
In this embodiment, the specific implementation processes of step S31 to step S33 for generating the frequency domain OFDM symbol may refer to the detailed descriptions of step S11 to step S13 in the method for generating the preamble symbol in the physical frame, which are not described herein again.
That is to say, based on the method for generating the frequency domain OFDM symbol provided in this embodiment, a person skilled in the art may use other embodiments (not limited to the foregoing steps S14 to S16) to process the frequency domain OFDM symbol to generate the preamble symbol in the time domain.
In summary, the technical solution ensures that an obvious peak can be obtained at a receiving end by using delay correlation by using the modulation signal of the time domain OFDM symbol and the structure of the time domain OFDM symbol (as a preamble symbol). Further, in the process of generating the preamble symbol, designing the modulation signal of the time domain OFDM symbol can avoid that the receiving end is subjected to continuous wave interference or single frequency interference, or a multipath channel with the same length as the modulation signal occurs, or a false detection peak occurs when the guard interval length in the received signal is the same as the length of the modulation signal.
Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make variations and modifications of the present invention without departing from the spirit and scope of the present invention by using the methods and technical contents disclosed above.

Claims (3)

1. A method for processing a received signal at a receiving end, comprising the steps of:
demodulating and delaying a received signal, and performing correlation operation on the delayed signal and the received signal to obtain a timing coarse synchronization position;
performing fast Fourier transform on the correlation value to obtain a frequency domain signal, and removing a fixed sequence from the frequency domain signal at a position to obtain a channel estimation value of a fixed sequence point;
performing Fourier inversion on the channel estimation value to obtain a time domain signal, wherein when an obvious peak value exists, the shift value is correct integer frequency offset, and the peak value also marks the position of the strongest path;
after time domain compensation integral multiple frequency offset, local correlation is carried out by utilizing a time domain sequence corresponding to a fixed sequence on a frequency domain, so that decimal frequency offset is calculated, and an accurate timing synchronization position is obtained;
and interpolating a channel estimation value of the signaling sequence by utilizing the channel estimation value of the fixed sequence point in a frequency domain, and then carrying out coherent demodulation to obtain the signaling.
2. The method as claimed in claim 1, comprising:
and performing fast Fourier transform on the correlation value to obtain a 1k frequency domain signal.
3. The method as claimed in claim 1, comprising:
wherein, the received signal is r (t), the received signal is demodulated by M (t):when f isSHMultiplying the received signal by 1/(1024T)Then, orderThe demodulated signal is delayed as: let r be2(t)=r1(t-1024)。
CN201611013351.1A 2014-03-28 2014-03-28 Processing method of received signals of receiving end Withdrawn CN106685877A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201611013351.1A CN106685877A (en) 2014-03-28 2014-03-28 Processing method of received signals of receiving end

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201410121324.0A CN104954309B (en) 2014-03-28 2014-03-28 The generation method of leading symbol and the generation method of frequency-domain OFDM symbol
CN201611013351.1A CN106685877A (en) 2014-03-28 2014-03-28 Processing method of received signals of receiving end

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
CN201410121324.0A Division CN104954309B (en) 2014-03-28 2014-03-28 The generation method of leading symbol and the generation method of frequency-domain OFDM symbol

Publications (1)

Publication Number Publication Date
CN106685877A true CN106685877A (en) 2017-05-17

Family

ID=54168669

Family Applications (3)

Application Number Title Priority Date Filing Date
CN201410121324.0A Active CN104954309B (en) 2014-03-28 2014-03-28 The generation method of leading symbol and the generation method of frequency-domain OFDM symbol
CN201611013351.1A Withdrawn CN106685877A (en) 2014-03-28 2014-03-28 Processing method of received signals of receiving end
CN201611013939.7A Withdrawn CN106603456A (en) 2014-03-28 2014-03-28 Generation method of preamble symbol and generation method of frequency-domain OFDM symbol

Family Applications Before (1)

Application Number Title Priority Date Filing Date
CN201410121324.0A Active CN104954309B (en) 2014-03-28 2014-03-28 The generation method of leading symbol and the generation method of frequency-domain OFDM symbol

Family Applications After (1)

Application Number Title Priority Date Filing Date
CN201611013939.7A Withdrawn CN106603456A (en) 2014-03-28 2014-03-28 Generation method of preamble symbol and generation method of frequency-domain OFDM symbol

Country Status (1)

Country Link
CN (3) CN104954309B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105007145A (en) * 2014-04-16 2015-10-28 上海数字电视国家工程研究中心有限公司 Method for generating preamble symbol and method for generating frequency domain OFDM symbol
CN105024963A (en) * 2014-04-30 2015-11-04 上海数字电视国家工程研究中心有限公司 Frequency domain OFDM symbol generation method and preamble symbol generation method
WO2024000744A1 (en) * 2022-06-29 2024-01-04 苏州大学 Optimized receiving method for optical universal filtered multi-carrier optical access network

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111490957B (en) * 2020-03-10 2023-06-16 北京睿信丰科技有限公司 Method and device for generating preamble sequence in time domain

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1227993A (en) * 1999-01-04 1999-09-08 北京邮电大学 Frame structure suitable for wide-band code division multiple access signal transmission
CN101170534A (en) * 2007-10-31 2008-04-30 中兴通讯股份有限公司 A timing rough synchronization capturing method for mobile multimedia broadcast system
CN101437005A (en) * 2008-12-12 2009-05-20 中国人民解放军理工大学通信工程学院 Method for estimating integer multiple frequency deviation with timing error during communication synchronization process
CN101945071A (en) * 2009-07-10 2011-01-12 中兴通讯股份有限公司 Confirming method of synchronization sequence in multipoint collaborative environment, synchronizing method and device
US20120087263A1 (en) * 2009-06-30 2012-04-12 Zte Corporation Method And Apparatus For Frequency Offset Estimation And Correction In Orthogonal Frequency Division Multiplexing System
CN103532898A (en) * 2013-04-22 2014-01-22 上海数字电视国家工程研究中心有限公司 OFDM training symbol generation and synchronization method based on CAZAC sequence

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8599764B2 (en) * 2003-09-02 2013-12-03 Qualcomm Incorporated Transmission of overhead information for reception of multiple data streams
CN1937604B (en) * 2005-09-20 2013-01-16 中兴通讯股份有限公司 Initial access frame synchronizing method and device for orthogonal frequency division multiplexing system
CN101374131B (en) * 2007-08-20 2013-01-30 株式会社Ntt都科摩 Method and apparatus of timing synchronization, leading symbol as well as method and apparatus for generating the same
CN101132268B (en) * 2007-09-13 2011-07-13 中兴通讯股份有限公司 Frame generation method based on orthogonal frequency division multiplexing technology in TDD mode
US8248910B2 (en) * 2008-01-29 2012-08-21 Nokia Corporation Physical layer and data link layer signalling in digital video broadcast preamble symbols
CN101695063B (en) * 2009-10-19 2011-12-21 中国电子科技集团公司第五十四研究所 Method for rapidly synchronizing short preamble symbols
CN103581096B (en) * 2013-03-25 2017-05-10 上海数字电视国家工程研究中心有限公司 OFDM modulating and demodulating method and digital signal emitting and receiving system
CN103532899B (en) * 2013-07-31 2016-07-06 上海数字电视国家工程研究中心有限公司 Time domain OFDM synchronizing symbol generates and demodulation method, data frame transmission method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1227993A (en) * 1999-01-04 1999-09-08 北京邮电大学 Frame structure suitable for wide-band code division multiple access signal transmission
CN101170534A (en) * 2007-10-31 2008-04-30 中兴通讯股份有限公司 A timing rough synchronization capturing method for mobile multimedia broadcast system
CN101437005A (en) * 2008-12-12 2009-05-20 中国人民解放军理工大学通信工程学院 Method for estimating integer multiple frequency deviation with timing error during communication synchronization process
US20120087263A1 (en) * 2009-06-30 2012-04-12 Zte Corporation Method And Apparatus For Frequency Offset Estimation And Correction In Orthogonal Frequency Division Multiplexing System
CN101945071A (en) * 2009-07-10 2011-01-12 中兴通讯股份有限公司 Confirming method of synchronization sequence in multipoint collaborative environment, synchronizing method and device
CN103532898A (en) * 2013-04-22 2014-01-22 上海数字电视国家工程研究中心有限公司 OFDM training symbol generation and synchronization method based on CAZAC sequence

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105007145A (en) * 2014-04-16 2015-10-28 上海数字电视国家工程研究中心有限公司 Method for generating preamble symbol and method for generating frequency domain OFDM symbol
CN105007145B (en) * 2014-04-16 2018-12-18 上海数字电视国家工程研究中心有限公司 The generation method of leading symbol and the generation method of frequency-domain OFDM symbol
CN105024963A (en) * 2014-04-30 2015-11-04 上海数字电视国家工程研究中心有限公司 Frequency domain OFDM symbol generation method and preamble symbol generation method
WO2024000744A1 (en) * 2022-06-29 2024-01-04 苏州大学 Optimized receiving method for optical universal filtered multi-carrier optical access network

Also Published As

Publication number Publication date
CN104954309A (en) 2015-09-30
CN106603456A (en) 2017-04-26
CN104954309B (en) 2019-05-03

Similar Documents

Publication Publication Date Title
CN105007145B (en) The generation method of leading symbol and the generation method of frequency-domain OFDM symbol
CN105007146B (en) The generation method of leading symbol in physical frame
CN105024791B (en) The generation method of leading symbol in physical frame
CN105282076B (en) The generation method of leading symbol and the generation method of frequency-domain OFDM symbol
US9948436B2 (en) Receiver and method of receiving
CN110190938B (en) Method for generating preamble symbol in physical frame
CN105024952B (en) The generation method of frequency-domain OFDM symbol and the generation method of leading symbol
US20170237591A1 (en) Transmitter, receiver and methods and computer readable medium
CN103379082B (en) Time-frequency synchronization method and device in LTE communication system
GB2532308A (en) Receiver and method of receiving
CN112039810B (en) Method for generating frequency domain OFDM symbol and method for generating preamble symbol
CN105282078B (en) The generation method of preprocess method and leading symbol to frequency-domain OFDM symbol
CN104954309B (en) The generation method of leading symbol and the generation method of frequency-domain OFDM symbol
GB2540595A (en) Receiver and method of receiving
US20180145864A1 (en) Receiver and method of receiving
KR101257015B1 (en) Methods of estimating timing offset using multi stage for timing synchronization and ofdm reciever
KR101242168B1 (en) Method for generating transmission signal including pre-conjugated preamble, method for detecting preamble from received signal including pre-conjugated preamble and method for restoring preamble from received signal including pre-conjugated preamble
KR101607196B1 (en) Method and apparatus for providing channel estimation of orthogonal frequency division multiplexing system
KR20140077418A (en) Apparatus and method for estimating OFDM channel using space frequency block coded training sequence

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WW01 Invention patent application withdrawn after publication

Application publication date: 20170517

WW01 Invention patent application withdrawn after publication