CN110213191B - FBMC-OQAM timing and channel estimation training sequence design method - Google Patents

FBMC-OQAM timing and channel estimation training sequence design method Download PDF

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CN110213191B
CN110213191B CN201910461412.8A CN201910461412A CN110213191B CN 110213191 B CN110213191 B CN 110213191B CN 201910461412 A CN201910461412 A CN 201910461412A CN 110213191 B CN110213191 B CN 110213191B
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CN110213191A (en
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丁丽琴
李黎明
汪洋
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Shenzhen Graduate School Harbin Institute of Technology
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2602—Signal structure
    • H04L27/261—Details of reference signals
    • H04L27/2613—Structure of the reference signals
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2655—Synchronisation arrangements
    • H04L27/2689—Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation
    • H04L27/2692—Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation with preamble design, i.e. with negotiation of the synchronisation sequence with transmitter or sequence linked to the algorithm used at the receiver
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2655—Synchronisation arrangements
    • H04L27/2689—Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation
    • H04L27/2695—Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation with channel estimation, e.g. determination of delay spread, derivative or peak tracking
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2626—Arrangements specific to the transmitter only
    • H04L27/2627—Modulators
    • H04L27/264—Pulse-shaped multi-carrier, i.e. not using rectangular window
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2697—Multicarrier modulation systems in combination with other modulation techniques
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Abstract

A method and a system for designing FBMC-OQAM timing and channel estimation training sequences relate to the field of wireless communication. The training sequence consists of three consecutive FBMC symbols, including two auxiliary data symbols and one pilot symbol located in the middle of the two auxiliary data symbols. The work subcarrier modulation data of the odd or even sequence number position of the pilot frequency symbol is set to zero, and the work subcarrier modulation data corresponding to the odd or even sequence number position of the two auxiliary data symbols are the same or opposite to each other, so that a sequence with conjugate symmetry property in a time domain is constructed, and the timing synchronization function can be completed through the conjugate symmetry property of the sequence. In addition, by utilizing the symmetrical characteristic of imaginary part interference on a time-frequency plane in the FBMC-OQAM system, the training sequence can be used for not only symbol timing synchronization but also frequency domain channel estimation after filtering of the FBMC-OQAM system.

Description

FBMC-OQAM timing and channel estimation training sequence design method
Technical Field
The invention relates to the field of wireless communication, in particular to a method for designing a training sequence for timing and channel estimation of FBMC-OQAM.
Background
In recent years, multicarrier modulation has been widely used in various communication systems as a communication waveform technique, and its basic idea is to divide a transmission bit stream into a plurality of sub-bit streams and modulate the sub-bit streams onto different sub-carriers for transmission. Among many multicarrier modulation techniques, orthogonal Frequency Division Multiplexing (OFDM) is widely used due to its advantages such as high spectrum efficiency, low transceiver complexity, simple equalization, and easy use in combination with multi-antenna techniques, for example, in the fourth generation Long Term Evolution (LTE) system, digital television Broadcast (DVB), wireless Local Area Network (WLAN), and the like.
With the isomerization and asynchronization Of future communication networks, OFDM has some disadvantages such as high Out Of Band (OOB) radiation, sensitivity to synchronization error, and the like. For example, mass wireless access of the internet of things, multipoint cooperative transmission, direct communication between devices, and the like all need to reduce the requirement of modulation waveforms for accurate synchronization, so as to meet the requirements of low cost and low signaling overhead while ensuring communication performance. In addition, cognitive radio, carrier aggregation, and other technologies also require that the signal modulation waveform have lower out-of-band leakage, so as to utilize the fragmented spectrum more efficiently. To address these challenges, filter Bank Multi-Carrier (FBMC) is considered a promising waveform technology due to its advantages of extremely low OOB radiation. In the FBMC system, OOB radiation is greatly reduced due to the introduction of a Prototype Filter (PF) having a good Time-Frequency focusing (TFL), so that Inter-Carrier Interference (ICI) can be effectively controlled, thereby flexibly and effectively utilizing Frequency spectrum resources and reducing synchronization requirements. FBMC has great advantages in asynchronous communication networks because it modulates very low OOB radiation. For example, in a massive internet of things, due to the number of terminals, synchronization between devices needs to consume a large amount of signaling resources, and the FBMC system can use good protection subcarriers to greatly reduce interference between asynchronous users, so that the signaling resources and the power consumption of terminal devices can be greatly saved. Meanwhile, in order to improve the spectrum utilization and cope with the non-orthogonality caused by the introduction of the prototype filter, the FBMC system usually adopts the Offset Quadrature Amplitude Modulation (OQAM) instead of the conventional QAM. In OQAM modulation, the complex data symbols transmitted by the original QAM modulation can be approximately equivalent to transmitting two real symbols in the same time, thereby keeping the spectral efficiency unchanged. That is, in the FBMC-OQAM system, the complex orthogonal property in the conventional OFDM needs to be relaxed to be the real number domain orthogonal, thereby providing a solution of the compromise of the spectrum efficiency-OOB radiation-orthogonality.
Based on the above characteristics of the FBMC-OQAM system, due to the introduction of the filter with good TFL characteristics, the FBMC symbol is partially overlapped in the time domain while the excellent OOB radiation performance is brought, which makes the synchronization sequence design of the FBMC system not as direct as in the OFDM system. Meanwhile, since the FBMC-OQAM system can only keep the orthogonality in the real number domain, the imaginary part of the received symbol will be interfered by other time frequency point symbols, which brings difficulty to the channel coefficient estimation with complex value. Therefore, the existence of the imaginary interference item makes the key of the channel estimation algorithm in the FBMC-OQAM system to solve how to eliminate the interference item or perform channel estimation by using the interference item, so as to improve the channel estimation accuracy of the FBMC-OQAM system.
Disclosure of Invention
The invention aims to construct a training sequence of FBMC-OQAM, and improve the frequency spectrum efficiency of the timing synchronization and channel estimation training sequence of the FBMC-OQAM system by utilizing the conjugate symmetry characteristic of signals in the FBMC-OQAM system.
According to a first aspect, an embodiment provides a method for designing a FBMC-OQAM timing and channel estimation training sequence, including:
acquiring a data symbol sequence to be transmitted;
generating a training sequence, wherein the training sequence is used for timing synchronization and frequency domain channel coefficient estimation of an FBMC-OQAM system;
the training sequence includes three consecutive FBMC symbols, respectively two auxiliary data symbols and one pilot symbol located in the two auxiliary data symbols, wherein:
the work sub-carriers of odd-numbered sequence numbers of the pilot symbols are set to be zero, the real modulation data of the work sub-carriers of the two auxiliary data symbols with the same even-numbered sequence numbers are the same, and the real modulation data of the work sub-carriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are opposite numbers;
or, the working subcarriers of even-numbered sequence numbers of the pilot symbols are set to zero, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are the same, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same even-numbered sequence numbers are opposite;
and inserting the training sequence into a data symbol sequence to be transmitted.
According to a second aspect, an embodiment provides an FBMC-OQAM timing and channel estimation training sequence design system, comprising:
the training sequence inserting module is used for acquiring a data symbol sequence to be transmitted so as to generate a training sequence and inserting the training sequence into the data symbol sequence to be transmitted;
wherein the training sequence is used for timing synchronization and frequency domain channel coefficient estimation of an FBMC-OQAM system;
the training sequence includes three consecutive FBMC symbols, respectively two auxiliary data symbols and one pilot symbol located in the two auxiliary data symbols, wherein:
the work sub-carriers of odd-numbered sequence numbers of the pilot symbols are set to be zero, the real modulation data of the work sub-carriers of the two auxiliary data symbols with the same even-numbered sequence numbers are the same, and the real modulation data of the work sub-carriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are opposite numbers;
or, the working subcarriers of even-numbered sequence numbers of the pilot symbols are set to zero, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are the same, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same even-numbered sequence numbers are opposite;
and the transmitting module is used for carrying out the baseband signal processing operation of the FBMC system through subcarrier modulation and polyphase filtering after carrying out OQAM phase factor weighting on the training symbols, and transmitting the training symbols to a channel after finishing carrier frequency modulation, filtering and amplification.
According to the FBMC-OQAM timing and channel estimation training sequence design method and system of the above embodiments, since on the subcarrier-symbol coordinates of the FBMC-OQAM system, the training sequence includes three consecutive FBMC symbols, which are two auxiliary data symbols and one pilot symbol located in the two auxiliary data symbols, respectively, a training sequence having a conjugate symmetry characteristic in the time domain is constructed, so that the imaginary intrinsic interferences caused by OQAM modulation cancel each other at the pilot signal point, and thus the training sequence can be used for timing synchronization and frequency domain channel coefficient estimation of the FBMC-OQAM system.
Drawings
FIG. 1 is a diagram illustrating a model structure of a baseband system of an FBMC-OQAM system according to an embodiment;
FIG. 2 is a schematic flow chart illustrating a method for designing FBMC-OQAM timing and channel estimation training sequences in an embodiment;
FIG. 3 is a diagram of an exemplary embodiment of a training sequence of FBMC-OQAM;
FIG. 4 is a flowchart illustrating a method for generating a training sequence of FBMC-OQAM according to an embodiment;
FIG. 5 is a diagram illustrating a model structure of a baseband system of an FBMC-OQAM system according to an embodiment;
FIG. 6 is a block diagram of an FBMC-OQAM polyphase decomposition architecture in accordance with an embodiment;
FIG. 7 is a diagram illustrating the conjugate symmetry of IFFT output signals of an OQAM system according to an embodiment;
FIG. 8 is a schematic time-domain waveform of a prototype filter in accordance with an embodiment;
FIG. 9 is a diagram illustrating exemplary training sequence time-frequency point structures;
FIG. 10 is a diagram illustrating the time domain composition and conjugate symmetry properties of a training sequence in an embodiment;
fig. 11 is a diagram of FBMC-OQAM modulation inherent imaginary interference in one embodiment.
Detailed Description
The present invention will be described in further detail with reference to the following detailed description and accompanying drawings. Wherein like elements in different embodiments are numbered with like associated elements. In the following description, numerous specific details are set forth in order to provide a better understanding of the present application. However, those skilled in the art will readily recognize that some of the features may be omitted or replaced with other elements, materials, methods in different instances. In some instances, certain operations related to the present application have not been shown or described in this specification in order not to obscure the core of the present application with unnecessary detail, and it is not necessary for those skilled in the art to describe these operations in detail, so that they may be fully understood from the description in the specification and the general knowledge in the art.
Furthermore, the features, operations, or characteristics described in the specification may be combined in any suitable manner to form various embodiments. Also, the various steps or actions in the method descriptions may be transposed or transposed in order, as will be apparent to one of ordinary skill in the art. Thus, the various sequences in the specification and drawings are for the purpose of describing certain embodiments only and are not intended to imply a required sequence unless otherwise indicated where such sequence must be followed.
The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" as used herein includes both direct and indirect connections (couplings), unless otherwise specified.
The terms used in this application define:
bold lowercase letters, representing row vectors, e.g., a;
bold capital letters, representing a matrix, e.g., a;
superscript T, representing the transpose of the matrix;
superscript H, which represents the conjugate transpose of the matrix;
lower case letters, without bolder, represent scalar values, e.g., a;
superscript, representing conjugate value;
j, an imaginary unit;
Figure GDA0003812787850000041
operating for a solid part;
Figure GDA0003812787850000042
to take the imaginary part.
Referring to fig. 1, a schematic diagram of a baseband system model structure of an FBMC-OQAM system in an embodiment includes a transmitting end and a receiving end. The sending end comprises a serial-parallel conversion module, an OQAM preprocessing module, an IFFT module and a multiphase filter module, and the receiving end comprises a multiphase filter module, an FFT module, an OQAM post-processing module and a parallel-serial conversion module. Because the data to be transmitted is complex data, the data to be transmitted is firstly processed by an OQAM preprocessing module and an OQAM preprocessing module after being subjected to serial-parallel conversionThe block serves to separate input complex data into two real data and is arranged in different sub-carriers or symbol periods. The method aims to separate the real part and the imaginary part of modulation data into two real parts to meet the requirement of OQAM real part orthogonality, then alternately arranging the real part and the imaginary part into two adjacent symbol periods in time, and multiplying the symbol periods by a phase modulation factor j corresponding to the nth symbol period and the mth subcarrier m+n Data which is virtually alternated on subcarrier and symbol arrangement is generated, and finally IFFT subcarrier modulation is carried out. That is, the OQAM modulation requires separation of real and imaginary parts of input complex data, and arrangement of the real and imaginary parts in different symbol periods.
At present, the design method of the synchronization sequence of the FBMC-OQAM mainly comprises the methods of adopting a sequence block method with the same front and back, utilizing the conjugate symmetry characteristic of the FBMC-OQAM signal to carry out synchronization, constructing a constant amplitude zero auto-correlation sequence and the like.
The same sequence block method is adopted to transmit continuous same data symbols to cope with the influence of symbol overlapping so as to construct two repeated signal blocks in a time domain signal to complete synchronization. The method is simple, but the method uses a large number of training symbols, and the frequency spectrum efficiency of the system is reduced.
The synchronization method by using the conjugate symmetry characteristic of the FBMC-OQAM signal mainly aims at the synchronization problem under the condition of burst transmission at present. By utilizing the conjugate symmetry characteristic of the FBMC-OQAM single-symbol time domain signal, the synchronous blind detection can be carried out by utilizing the conjugate symmetry characteristic at the initial stage of the signal, namely the subsequent stage with less symbol interference. In addition, the frequency spectrum efficiency can be improved by a method of storing preset data, and two identical conjugate symmetrical training sequence blocks are constructed at the signal starting stage, so that the synchronization performance is improved.
The method for constructing the Constant Amplitude Zero autocorrelation sequence calculates a specific training symbol value through the FBMC symbol aliasing principle, so that two Constant Amplitude Zero Auto Correlation (CAZAC) sequences are constructed in a time domain for synchronization.
The channel estimation of the FBMC-OQAM system is mainly divided into two types, namely, pilot type and scattered pilot type. The preamble is mainly used for data burst transmission, while the distributed pilot is more applied to continuous information transmission, provides distributed channel estimation on a time-frequency plane, and completes channel estimation on the whole time-frequency plane by interpolation. The pilot channel estimation schemes mainly include three, namely a pilot pair method, an interference approximation method and an interference cancellation method. The pilot frequency pair method constructs a linear equation set related to channel coefficients at two moments at a receiving end by sending two continuous training symbols, and if the channel change is not fast, the channel coefficients at the two moments can be considered to be the same, and then solution equation solution is carried out. The pilot frequency pair method is simple to implement, but the solving process of the channel coefficient is greatly influenced by noise, so that the performance degradation is serious at low signal-to-noise ratio. The interference approximation method is based on the fact that the target pilot symbol is mainly interfered by the imaginary parts of the surrounding adjacent symbols, and if the surrounding symbol data are known as well, the exact value of the imaginary interference can be calculated to assist the channel estimation. The interference cancellation method is opposite to the interference approximation method, and the values of the symbols around the training sequence are set to cancel the respective interference, because the symbols around the scheme can still transmit data, the spectrum utilization efficiency can be improved on the premise of completing the channel estimation.
The channel estimation of the distributed pilot frequency emphasizes the utilization rate of frequency spectrum compared with the pilot mode because the number of the pilot frequencies is larger. There are two commonly used methods at present, which are an Auxiliary Pilot (AP) and a Data Spreading (DS) method. The idea of the AP method is to use a data symbol adjacent to a pilot training symbol as an auxiliary pilot symbol, and calculate the value of the auxiliary pilot symbol to cancel the imaginary interference of other data symbols around the pilot symbol. The method is simple in implementation scheme, but the power of the AP symbol is far higher than that of the ordinary data symbol, and the energy efficiency is reduced. To improve energy efficiency, the DS method is to linearly encode adjacent pilot symbols and decode them at the receiving end to calculate channel coefficients, such as the downlink of LTE.
At present, how to reduce the frequency spectrum efficiency reduction caused by the synchronous training sequence overhead is still a problem of concern, and on the premise of keeping high frequency spectrum efficiency, a training sequence design method combining synchronous channel estimation and frequency domain channel estimation is relatively limited.
In the embodiment of the invention, aiming at a continuous data transmission mode, the invention provides a training sequence pattern for joint timing synchronization channel and frequency domain channel estimation, because real number modulation data points of a training sequence comprise two columns of information data sequences and one column of pilot frequency sequences on a subcarrier-symbol coordinate of an FBMC-OQAM system, the pilot frequency sequences are arranged between the two columns of information data sequences, the training sequence with conjugate symmetry characteristics in a time domain is constructed, so that inherent imaginary part interference brought by OQAM modulation is mutually offset at the pilot frequency signal points, and the training sequence can be used for the synchronization channel and the frequency domain channel estimation after filtering.
Example one
Referring to fig. 2, a flow chart of an embodiment of a method for designing FBMC-OQAM timing and channel estimation training sequences is shown, the method comprising:
step one, a data symbol sequence to be transmitted is obtained.
The transmitting end of the FBMC-OQAM system groups original data to be transmitted and performs serial-parallel conversion on each group of original data to obtain a data symbol sequence to be transmitted. In one embodiment, each FBMC symbol comprises an even number of active subcarriers, and each active subcarrier in the FBMC symbol is sorted in the order of their rank numbers 0,1,2, … M-1,M being an even number greater than 0.
And step two, generating a training sequence.
The training sequence is used for timing synchronization and frequency domain channel coefficient estimation of the FBMC-OQAM system. Referring to fig. 3, a schematic diagram of a training sequence structure of FBMC-OQAM in an embodiment, where a data symbol sequence of subcarrier-symbol coordinates of an FBMC-OQAM system includes three consecutive FBMC symbols, i.e. an auxiliary data symbol 101, an auxiliary data symbol 103, and a pilot symbol 102 located in two auxiliary data symbols, respectively, of a training sequence 10, where:
the work sub-carrier of odd number sequence number bit of pilot frequency symbol is set to zero, and the real number modulation data of the work sub-carrier of even number sequence number bit that two auxiliary data symbols are the same, and the real number modulation data of the work sub-carrier of odd number sequence number bit that two auxiliary data symbols are the same number of opposite each other. Or, the working sub-carriers of the even-numbered sequence numbers of the pilot symbols are set to zero, the real modulation data of the working sub-carriers of the odd-numbered sequence numbers of the two auxiliary data symbols are the same, and the real modulation data of the working sub-carriers of the even-numbered sequence numbers of the two auxiliary data symbols are opposite numbers to each other. In an embodiment, the working sub-carrier with odd-numbered bits of the pilot symbol 102 is set to zero, the real modulation data of the working sub-carriers with even-numbered bits of the two auxiliary data symbols are the same, and the real modulation data of the working sub-carriers with odd-numbered bits of the two auxiliary data symbols are opposite numbers to each other. In an embodiment, any one of the auxiliary data symbols 101 and 103 is a data symbol to be transmitted. In an embodiment, pilot data and real modulation data to be transmitted are placed on the non-zeroed working subcarriers of the pilot symbols 102. In one embodiment, the pilot symbols 102 have pilot data placed on all non-zero active subcarriers. In one embodiment, the pilot symbol 102 data is a set of pseudo-random sequences.
Referring to fig. 4, a flow chart of a method for generating a training sequence of FBMC-OQAM in an embodiment is shown, where the method includes:
step 1, obtaining a data symbol to be transmitted at a pre-insertion position.
And acquiring a data symbol to be transmitted at a pre-insertion position on a data symbol sequence of a subcarrier-symbol coordinate of the FBMC-OQAM system.
And 2, taking the acquired data symbol to be transmitted as an auxiliary data symbol of the training sequence.
And 3, acquiring another auxiliary data symbol according to the data symbol to be transmitted.
And acquiring another auxiliary data symbol according to the fact that the real modulation data of the two auxiliary data symbols on the working subcarriers with the same even-number sequence number are the same and the real modulation data of the working subcarriers with the same odd-number sequence number are opposite numbers.
Or, another auxiliary data symbol is obtained according to the fact that the real modulation data of the two auxiliary data symbols on the working subcarriers with the same odd-numbered sequence number bits are the same and the real modulation data of the working subcarriers with the same even-numbered sequence number bits are opposite numbers.
And 4, inserting the pilot symbols between the two auxiliary data symbols to form a training sequence.
And step three, inserting the training sequence into the data symbol sequence.
And inserting the generated training sequence into the position of the data symbol to be transmitted, which is obtained in the first step.
And step four, modulating the data symbol sequence and then sending the modulated data symbol sequence to a channel.
And carrying out OQAM phase factor weighting on the data symbol sequence to be transmitted inserted into the training sequence, then carrying out FBMC system baseband signal processing operation through subcarrier modulation and polyphase filtering, and sending the data symbol sequence to be transmitted into a channel after carrier frequency modulation, filtering and amplification are completed.
Referring to fig. 5, a schematic diagram of a baseband system model structure of an FBMC-OQAM system in an embodiment is shown, where the FBMC-OQAM system includes a transmitting end and a receiving end. The transmitting end of the FBMC-OQAM system comprises a serial-to-parallel conversion module 21, a training sequence insertion module 22 and a transmitting module. The serial-to-parallel conversion module 21 is configured to group the original data to be transmitted, and perform serial-to-parallel conversion on each group of original data to obtain a data symbol sequence to be transmitted. The training sequence inserting module 22 is configured to obtain a data symbol sequence to be transmitted, to generate a training sequence, and insert the training sequence into the data symbol sequence to be transmitted, where the training sequence is used for timing synchronization and/or frequency domain channel coefficient estimation of the FBMC-OQAM system. The training sequence comprises three continuous FBMC symbols which are respectively two auxiliary data symbols and one pilot symbol positioned in the two auxiliary data symbols, wherein working subcarriers of odd-numbered sequence numbers of the pilot symbols are set to be zero, real modulation data of the working subcarriers of the two auxiliary data symbols with the same even-numbered sequence numbers are the same, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are opposite numbers. The transmitting module is used for carrying out the baseband signal processing operation of the FBMC system through subcarrier modulation and polyphase filtering after carrying out OQAM phase factor weighting on the training symbols, and transmitting the training symbols to a channel after finishing carrier frequency modulation, filtering and amplification. The transmission block includes an OQAM pre-processing block 23, an IFFT block 24 and a pre-polyphase filtering block 25. The OQAM pre-processing block 23 is configured to perform OQAM phase factor weighting on the training sequence and the common information data symbols. The FFT block 24 is used for subcarrier modulation. The pre-polyphase filtering module 25 is used for processing baseband signals of the FBMC system, and transmits the processed signals to a channel after carrier frequency modulation, filtering and amplification are completed. The transmitting end of the FBMC-OQAM system inserts a training sequence into a data symbol sequence to be transmitted, carries out FBMC system baseband signal processing operation of subcarrier modulation and polyphase filtering after OQAM phase factor weighting, and sends the signal to a channel after carrier frequency modulation, filtering and amplification are completed.
The receiving end of the FBMC-OQAM system comprises a synchronization module 31, a post-polyphase filtering module 32, an FFT module 33, a channel estimation module 34, a demodulation module 35, an OQAM post-processing module 36 and a parallel-to-serial conversion module 37. The synchronization channel module 31 is configured to perform symbol timing detection on the time domain received signal by using the conjugate symmetry property, and determine a start position of the pilot symbol. The post-polyphase filter module 32 is configured to polyphase filter the baseband signals received from the channel, and the FFT module 33 is configured to FFT-convert the data symbols for subcarrier demodulation. The channel estimation module 34 is used to detect the frequency domain channel coefficients. The demodulation module 35 and the OQAM post-processing module 36 are configured to perform OQAM demodulation on the data symbols to obtain estimated values of the common information data symbols. The parallel-serial conversion module 37 is configured to output the estimated value of the common information data symbol after parallel-serial conversion. The symbol timing detection of the time domain received signal by the synchronization channel module 32 using the conjugate symmetry property includes:
let r (k) be the received time domain baseband signal, k be the sampling time sequence number, M be the number of working subcarriers of the FBMC-OQAM system, F be the subcarrier bandwidth, the receiver sampling frequency be MF, and W (g) be the autocorrelation timing metric function for symbol timing:
Figure GDA0003812787850000081
wherein | is a get amplitude operation, and
Figure GDA0003812787850000091
Figure GDA0003812787850000092
timing estimator
Figure GDA0003812787850000093
Is composed of
Figure GDA0003812787850000094
Wherein the content of the first and second substances,
Figure GDA0003812787850000095
m is the number of working sub-carriers of the FBMC-OQAM system in order to obtain the value of a timing deviation estimation parameter g for maximizing W (g).
The receiving end of the FBMC-OQAM system performs FFT subcarrier demodulation and filtering on the signals which finish timing synchronization to obtain a frequency domain receiving signal y on the 2m subcarrier on a pilot frequency symbol (assumed as the nth symbol period) 2m，n The channel estimation module 34 detects the channel coefficient h of the frequency domain by single-point zero forcing 2m，n ＝y 2m，n /x 2m，n Wherein x is 2m，n Representing the pilot sequence values on that subcarrier.
Based on the present embodiment, the implementation idea of the technical solution of the present application is explained from the principle of multi-carrier modulation of FBMC-OQAM system. Since the FBMC-OQAM baseband transmission signal is formed by overlapping M subcarrier signals, generally M =2 L And the value range of L is a natural number larger than 2. The baseband transmit signal s (t) of FBMC-OQAM containing M subcarriers can be expressed as:
Figure GDA0003812787850000096
where (m, n) represents the mth subcarrier and the nth symbol period,
Figure GDA0003812787850000097
and
Figure GDA0003812787850000098
real data symbols, j, sent on even and odd subcarriers, respectively (2m+n) For the OQAM modulation phase factor term, p (T) is the prototype filter, T and F are the symbol period and subcarrier spacing, respectively, and TF =1/2 is satisfied.
If so, the
Figure GDA0003812787850000099
Sampling a baseband transmit signal s (t) for a period, where f s For the sampling rate, assume f in this patent s = MF, the discrete baseband transmit signal s (k) can be expressed as:
Figure GDA00038127878500000910
wherein k is a discrete sampling number.
For analytical convenience, we represent the baseband signal in matrix form, i.e., s (k) in vector form s. Referring to FIG. 6, an exemplary FBMC-0QAM polyphase decomposition scheme is shown, where s is represented by a plurality of FBMC symbols t n The shift superposition result of (2).
p represents the prototype filter signal vector, and the sample point length of the prototype filter can be regarded as KM, where K is an overlap Factor (Overlapping Factor), where the first sample data is 0, and the remaining KM-1 data points are generally real and centrosymmetric.
The further vector p can be written in the form of a block vector:
Figure GDA00038127878500000911
wherein the superscript T represents the transpose of the matrix, the vector
Figure GDA00038127878500000912
The ith block representing p,
Figure GDA0003812787850000101
representing the corresponding sample points.
In FIG. 6, a n Representing the input data vector as sub-carriers
Figure GDA00038127878500001016
Because the OQAM modulated data can be regarded as real numbers and imaginary numbers alternately arranged on subcarriers, the input data vector is output by Inverse Fast Fourier Transform (IFFT)
Figure GDA0003812787850000102
Can be expressed as:
Figure GDA0003812787850000103
if the data on the even subcarriers and the odd subcarriers are extracted separately, an even subcarrier input data vector and an odd subcarrier input data vector can be formed:
Figure GDA0003812787850000104
Figure GDA0003812787850000105
at this time, a n Can be represented by a n，1 And a n，2 The two parts are as follows:
Figure GDA0003812787850000106
wherein the content of the first and second substances,
Figure GDA0003812787850000107
f is the fourier transform matrix and superscript H is the conjugate transpose of the matrix.
The diagonal matrix E is:
E＝diag([1，e π/(M/2) ，e 2π/(M/2) ，...，e (M/2-1)π/(M/2) ] T ) (8)
in this case, diag (a) represents a diagonal matrix having a vector a as a diagonal element.
According to fig. 6, the signal t of the nth FBMC symbol n Can be expressed as:
Figure GDA0003812787850000108
wherein the content of the first and second substances,
Figure GDA0003812787850000109
and
Figure GDA00038127878500001010
respectively representing the Kronecker product and the Hadamard product, t n，i Representing the ith signal data block, then:
Figure GDA00038127878500001011
the last nth baseband output signal data block can be regarded as being formed by overlapping 2K data blocks:
Figure GDA00038127878500001012
since the characteristics of the OQAM modulated input data and the nature of the fourier transform are known,
Figure GDA00038127878500001013
and
Figure GDA00038127878500001014
respectively, a conjugate symmetric sequence and a conjugate negative symmetric sequence, so that the IFFT outputs a n Also has the characteristic of conjugate symmetry, please refer to fig. 7, which is a schematic diagram of conjugate symmetry of IFFT output signals of the polyphase decomposition OQAM modulation system in an embodiment, a n，1 And a n，2 Respectively a n，0 Contains two sets of sequences with conjugate symmetry about respective center points.
FIG. 8 is a schematic time-domain waveform of a prototype filter according to an embodiment, although s n The data block is formed by superposing 2K different symbol data blocks, but the energy is mainly concentrated in two adjacent data blocks. Hence in the following we will refer to s n′ ，＝s n+K The approximation is:
Figure GDA00038127878500001015
in the above formula and hereinafter, n is assumed to be a multiple of 4, so that j in the formula (9) is omitted n A phase factor term. The factor term can change the constructed training sequence from conjugate symmetry to conjugate negative symmetry, which is called conjugate symmetry in the patent.
Please refer to fig. 9, which is a schematic diagram of a time-frequency point structure of a training sequence in an embodiment, in order to recover the conjugate symmetry of FBMC baseband signals, pilot symbols are placed on even subcarriers of an nth symbol, and odd subcarriers are left blank; the even subcarrier data symbol of the (n + 1) th symbol is equal to the even subcarrier data symbol of the (n-1) th symbol, and the odd subcarrier data symbol of the (n + 1) th symbol is set as the opposite number of the odd subcarrier data of the (n-1) th symbol. This time is:
Figure GDA0003812787850000111
Figure GDA0003812787850000112
referring to fig. 10, a schematic diagram of the time domain composition and conjugate symmetry characteristics of the training sequence in an embodiment is shown, and according to the above formula and the time domain signal structure diagram shown in fig. 10, it can be found that the IFFT outputs a of the (n + 1) th and (n-1) th symbols can be found in consideration of the conjugate symmetry of the output of the OQAM modulation IFFT n+1 And a n-1 The head and the tail are conjugated and symmetrical with each other. And the IFFT output a of the nth symbol n A in (a) n，1 And a n，2 And are mutually in conjugate symmetry. Thus, the training sequence generates a block s of time domain signals n‘ And s n‘-1 Comprising two signal blocks of length M/2-1 which are in conjugate symmetry with each other. And the symmetric sequence of the time domain conjugate can be used as the timing synchronization of the receiving end.
Similarly, the operations on the odd and even subcarriers are interchanged, that is, pilot symbols are placed on odd subcarriers and the auxiliary data on both sides of the pilot symbols are the same, pilot symbols on even subcarriers are null, and the modulated data on the odd subcarriers of the auxiliary data symbols on both sides are opposite, so that training sequences with the same properties can be obtained.
The timing synchronization detection method for such a time-domain conjugate symmetric training sequence will be described below. Specifically, assuming r (k) is the received time domain signal, the autocorrelation timing metric function W (g) can be expressed as:
Figure GDA0003812787850000113
wherein | is a get amplitude operation, and
Figure GDA0003812787850000114
Figure GDA0003812787850000115
timing estimator
Figure GDA0003812787850000116
Is composed of
Figure GDA0003812787850000117
Wherein the content of the first and second substances,
Figure GDA0003812787850000118
the parameter g is calculated to maximize W (g).
In addition to the above-mentioned conjugate symmetry property, the training sequence can also be used as a channel estimate. Due to the particularity of OQAM real-quadrature modulation, inherent imaginary part interference exists between time-frequency point symbols at a receiving end. Taking a Hermite filter as an example, assume that a certain time-frequency signal point is taken as a center, and the influence of the surrounding signal point data on the point is given. Referring to fig. 11, which is a schematic diagram of the imaginary part interference inherent to FBMC-OQAM modulation in an embodiment, it can be observed from fig. 11 that the interference distribution of the surrounding signal points is in (positive and negative) symmetric relationship, and also since the interference is mainly concentrated on the adjacent signal points, we can approximately consider only the influence of the adjacent signal points as before. Combining the interference symmetry relationship of fig. 11 and the sequence value setting of the training region of fig. 9, it can be found that the interference from the adjacent signal points at the pilot signal points in the training region exactly cancels out positively and negatively. Thus, the pilot signal point can be considered as not being interfered, and thus it can be used as a channel estimate, i.e. the filtered frequency domain channel coefficient h at the mth subcarrier in the nth symbol m，n Comprises the following steps:
Figure GDA0003812787850000121
wherein x is m，n For pilot data symbol values, y m，n The received filtered frequency domain signal value is mapped to the signal point.
In the embodiment of the application, an FBMC-OQAM continuous data transmission training sequence with high spectral efficiency is provided, which is composed of a pilot symbol with null odd number sub-carriers and training symbols with same load data of two even number sub-carriers, wherein the load data of the odd number sub-carriers are opposite numbers. The training sequence has the conjugate symmetry characteristic in the time domain, the timing synchronization function can be completed through the characteristic, meanwhile, due to the numerical value relationship in the training symbols, the inherent imaginary part interference caused by the OQAM is mutually offset at the pilot signal point, and therefore the training sequence can also be used for frequency domain channel estimation after filtering.
The present invention has been described in terms of specific examples, which are provided to aid understanding of the invention and are not intended to be limiting. Numerous simple deductions, modifications or substitutions may also be made by those skilled in the art in light of the present teachings.

Claims (8)

1. A method for designing training sequences for timing and channel estimation of FBMC-OQAM comprises the following steps:
acquiring a data symbol sequence to be transmitted;
generating a training sequence, wherein the training sequence is used for timing synchronization and frequency domain channel coefficient estimation of an FBMC-OQAM system;
the training sequence includes two auxiliary data symbols and three consecutive FBMC symbols of a pilot symbol located in between the two auxiliary data symbols, wherein:
in a time-frequency plane, setting the working subcarriers of odd-numbered sequence numbers of the pilot symbols to zero, and setting the real modulation data of the working subcarriers of the two auxiliary data symbols with the same even-numbered sequence numbers to be the same, wherein the real modulation data of the working subcarriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are opposite numbers;
or, the working subcarriers of even-numbered sequence numbers of the pilot symbols are set to zero, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are the same, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same even-numbered sequence numbers are opposite numbers to each other;
inserting the training sequence into a data symbol sequence to be transmitted; pilot data and real number modulation data to be transmitted are all placed on the non-zero working subcarriers of the pilot symbols;
the FBMC-OQAM system generates a time domain signal according to the data symbol sequence to be transmitted after the training sequence is inserted and sends out the time domain signal;
a receiving end of the FBMC-OQAM system receives a time domain signal containing the training sequence in a time domain, and completes timing synchronization by utilizing autocorrelation detection according to the conjugate symmetry characteristic of the time domain signal generated by the training sequence;
the completing timing synchronization by utilizing autocorrelation detection according to the conjugate symmetry characteristic of the time domain signal generated by the training sequence comprises:
the autocorrelation timing metric function for symbol timing is represented as:
W（g）=|V 1 （g）|／U 1 （g）；
Figure DEST_PATH_IMAGE001
；
Figure DEST_PATH_IMAGE002
；
wherein the content of the first and second substances,W(g) For the autocorrelation timing metric function, | | is a fetch amplitude operation,r(k) For the received time domain baseband signal, k is the sample time sequence number,Mthe number of working subcarriers of the FBMC-OQAM system is set;
the timing estimation point
Figure DEST_PATH_IMAGE003
Comprises the following steps:
Figure DEST_PATH_IMAGE004
；
wherein the content of the first and second substances,
Figure DEST_PATH_IMAGE005
to make an effort toW（g) The maximum timing deviation estimation parameter g value.
2. The method of claim 1, wherein any one of the two secondary data symbols is a data symbol to be transmitted.
3. The method of claim 1, wherein the pilot data is a set of pseudo-random sequences.
4. The method of claim 1, wherein the generating the training sequence comprises:
acquiring a data symbol to be transmitted at a pre-insertion position;
taking the data symbol to be transmitted as the auxiliary data symbol;
acquiring another auxiliary data symbol according to the data symbol to be transmitted;
and inserting the pilot symbols into the middle of the two auxiliary data symbols to form the training sequence.
5. The method of claim 4, wherein the inserting the training sequence into the sequence of data symbols to be transmitted comprises:
and inserting the training sequence into the position of the data symbol to be transmitted in the pre-insertion position.
6. The method of claim 4, wherein said obtaining another of said auxiliary data symbols from said data symbol to be transmitted comprises:
and acquiring another auxiliary data symbol according to the fact that the real modulation data of the two auxiliary data symbols on the same working subcarrier with the even or odd ordinal number are the same and the real modulation data of the two auxiliary data symbols on the same working subcarrier with the odd or even ordinal number are opposite to each other.
7. The method of claim 1, further comprising:
and carrying out the baseband signal processing operation of the FBMC system through subcarrier modulation and polyphase filtering after carrying out OQAM phase factor weighting on a data symbol sequence to be transmitted, and sending the data symbol sequence to a channel after completing carrier frequency modulation, filtering and amplification.
8. An FBMC-OQAM timing and channel estimation training sequence design system, comprising:
the training sequence inserting module is used for acquiring a data symbol sequence to be transmitted so as to generate a training sequence and inserting the training sequence into the data symbol sequence to be transmitted;
wherein the training sequence is used for timing synchronization and frequency domain channel coefficient estimation of an FBMC-OQAM system;
the training sequence includes three consecutive FBMC symbols, respectively two auxiliary data symbols and one pilot symbol located in between the two auxiliary data symbols, wherein:
the work sub-carriers of odd-numbered sequence numbers of the pilot symbols are set to be zero, the real modulation data of the work sub-carriers of the two auxiliary data symbols with the same even-numbered sequence numbers are the same, and the real modulation data of the work sub-carriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are opposite numbers;
or, the working subcarriers of even-numbered sequence numbers of the pilot symbols are set to zero, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same odd-numbered sequence numbers are the same, and the real modulation data of the working subcarriers of the two auxiliary data symbols with the same even-numbered sequence numbers are opposite numbers to each other;
pilot data and real number modulation data to be transmitted are all placed on the non-zero working subcarriers of the pilot symbols;
the transmitting module is used for carrying out OQAM phase factor weighting on the training symbol to be transmitted after the training sequence is inserted, then carrying out FBMC system baseband signal processing operation of subcarrier modulation and polyphase filtering, and transmitting the symbol to be transmitted to a channel after carrier frequency modulation, filtering and amplification are completed;
the receiving end is used for receiving a time domain signal generated by the training sequence in a time domain and completing timing synchronization by utilizing autocorrelation detection according to the conjugate symmetry characteristic of the time domain signal generated by the training sequence;
the completing timing synchronization by utilizing autocorrelation detection according to the conjugate symmetry characteristics of the time domain signal generated by the training sequence comprises:
the autocorrelation timing metric function for symbol timing is represented as:
W（g）=|V 1 （g）|／U 1 （g）；
Figure DEST_PATH_IMAGE006
；
Figure DEST_PATH_IMAGE007
；
wherein the content of the first and second substances,W(g) For the autocorrelation timing metric function, | | is a fetch amplitude operation,r(k) For the received time domain baseband signal, k is the sample time sequence number,Mthe number of working subcarriers of the FBMC-OQAM system is set;
the timing estimation point
Figure DEST_PATH_IMAGE008
Comprises the following steps:
Figure DEST_PATH_IMAGE009
；
wherein the content of the first and second substances,
Figure DEST_PATH_IMAGE010
to make an effort toW(g) The maximum timing deviation estimation parameter g value.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108600142A (en) * 2018-03-27 2018-09-28 西安电子科技大学 A kind of synchronous method in FBMC/OQAM systems

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016018032A1 (en) * 2014-07-28 2016-02-04 Samsung Electronics Co., Ltd. Method and apparauts for performing sequence synchronization in mobile communication system
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CN109600334B (en) * 2019-01-04 2021-08-31 哈尔滨工业大学（深圳） OFDM synchronization method and device for bandwidth satellite communication system and readable storage medium

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108600142A (en) * 2018-03-27 2018-09-28 西安电子科技大学 A kind of synchronous method in FBMC/OQAM systems

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
FBMC/OQAM系统符号定时同步算法改进;任壮等;《广东通信技术》;20180115(第01期);全文 *

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