CN114513396A - Pilot frequency method and system based on OFDM/OQAM under industrial 5G - Google Patents

Pilot frequency method and system based on OFDM/OQAM under industrial 5G Download PDF

Info

Publication number
CN114513396A
CN114513396A CN202210417445.4A CN202210417445A CN114513396A CN 114513396 A CN114513396 A CN 114513396A CN 202210417445 A CN202210417445 A CN 202210417445A CN 114513396 A CN114513396 A CN 114513396A
Authority
CN
China
Prior art keywords
data
pilot
channel
pilot frequency
discrete
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.)
Granted
Application number
CN202210417445.4A
Other languages
Chinese (zh)
Other versions
CN114513396B (en
Inventor
万亚东
张超
张波
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.)
University of Science and Technology Beijing USTB
Innotitan Intelligent Equipment Technology Tianjin Co Ltd
Original Assignee
University of Science and Technology Beijing USTB
Innotitan Intelligent Equipment Technology Tianjin 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 University of Science and Technology Beijing USTB, Innotitan Intelligent Equipment Technology Tianjin Co Ltd filed Critical University of Science and Technology Beijing USTB
Priority to CN202210417445.4A priority Critical patent/CN114513396B/en
Publication of CN114513396A publication Critical patent/CN114513396A/en
Application granted granted Critical
Publication of CN114513396B publication Critical patent/CN114513396B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/0202—Channel estimation
    • H04L25/0224—Channel estimation using sounding signals
    • H04L25/0228—Channel estimation using sounding signals with direct estimation from sounding signals
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0048—Allocation of pilot signals, i.e. of signals known to the receiver
    • 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

The invention relates to a pilot frequency method and a pilot frequency system based on OFDM/OQAM under industrial 5G, belonging to the technical field of pilot frequency design. The method comprises the steps of mapping binary bit streams to obtain QAM data sets, inserting discrete pilot frequency data into the QAM data sets according to a preset rule to obtain first data streams, performing serial-parallel conversion on complex data in the first data streams to obtain second data streams, then placing IAM-new pilot frequency data in front of the second data streams to obtain pilot data streams, performing discrete processing on channel estimation values to obtain discrete pilot estimation values after channel estimation values are obtained based on the pilot data streams, then performing first-order linear interpolation processing on the discrete pilot estimation values based on the channel estimation values to obtain channel information of each row of pilot data streams, demodulating the channel information to obtain demodulated binary data streams, so that the BER of demodulated information of a receiving end can be reduced, and the robustness of a falling-resistant channel of an OFDM/OQAM system is enhanced.

Description

Pilot frequency method and system based on OFDM/OQAM under industrial 5G
Technical Field
The invention relates to the technical field of pilot frequency design, in particular to an OFDM/OQAM pilot frequency method and system based on industrial 5G.
Background
Industrial 5G means that the communication system has faster transmission speed and higher transmission efficiency, and also means that the communication system has better adaptability to fast fading channels and has wider application space and scenes. At present, an OFDM/OQAM (orthogonal frequency division multiplexing/OQAM) modulation system based on OFDM/OQAM interleaved orthogonal modulation is an important component in 5G technology, and has approximately ideal transmission efficiency under an Additive White Gaussian Noise (AWGN) channel. Meanwhile, the FDM/OQAM has better fast fading channel adaptability compared with the traditional OFDM added with Cyclic Prefix (CP) due to the adoption of a pulse shaping function with better time-frequency energy aggregation, so that the FDM/OQAM has better application prospect.
Although the OFDM/OQAM system has a good capability of resisting a fast fading channel, since the pulse shaping function value of the OFDM/OQAM system satisfies real number domain orthogonality, the information at the receiving end is susceptible to interference of multipath channels and doppler frequencies, thereby causing interference of the receiving information to an imaginary part.
In order to estimate and equalize the channel for the imaginary part interference, for the multi-carrier modulation system, in the trade-off between the computational complexity and the efficiency, the channel state is mainly acquired in the form of pilot frequency, and the information is equalized. In a fast fading channel, the estimation of information is not separated from the design of the pilot. The current pilot design is mainly Interference Adaptation Method (IAM) series pilots. The pilot design is good for estimating a quasi-stationary channel, but in a fast fading channel, the pilot design method causes inaccurate results of subsequent channels. Inaccurate channel estimation can increase Bit Error Rate (BER) of a received signal, so that under a fast fading channel, information needs to have known information at all times, a real-time state of the channel can be acquired, and BER of demodulated information at a receiving end is reduced. Therefore, a design mode of scattered pilot is provided, and the technical problem to be solved in the field is to enhance the robustness of the anti-drop channel of the OFDM/OQAM system.
Disclosure of Invention
The invention aims to provide a pilot frequency method and a pilot frequency system based on OFDM/OQAM under industrial 5G, which can reduce BER of demodulation information of a receiving end and further enhance the robustness of a drop-resistant channel of the OFDM/OQAM system.
In order to achieve the purpose, the invention provides the following scheme:
a pilot frequency method based on OFDM/OQAM under industrial 5G comprises the following steps:
carrying out QAM mapping on the binary bit stream to obtain a QAM data set;
inserting a discrete pilot frequency data between every L-1 QAM data in the QAM data set to obtain a first data stream; the first data stream is a data matrix with N columns and K rows;
performing serial-parallel conversion on the complex data in the first data stream to obtain a second data stream; the second data stream is a data matrix with K columns and N rows;
placing IAM-new pilot frequency data in front of the second data flow to obtain a pilot frequency data flow;
obtaining a channel estimation value based on the pilot data stream;
performing discrete processing on the channel estimation value to obtain a discrete pilot frequency estimation value;
performing first-order linear interpolation processing on the discrete pilot frequency estimated value based on the channel estimated value to obtain channel information of each row of pilot frequency data streams;
and demodulating the channel information to obtain a demodulated binary data stream.
Preferably, the performing serial-to-parallel conversion on the complex data in the first data stream to obtain a second data stream specifically includes:
using a model
Figure 100002_DEST_PATH_IMAGE001
Performing serial-parallel conversion on the complex data in the first data stream to obtain conversion data;
wherein D is the second data stream,d 1is the first complex number data, and the first complex number data,d 2for the second one of the complex number data,d 3as the third complex number data, the first complex number data,d Kfor the Kth complex data, T is the transpose of the matrix, and each complex data includes N data.
Preferably, the scattered pilot distribution model of the second data stream is:
Figure 469304DEST_PATH_IMAGE002
；
Figure 100002_DEST_PATH_IMAGE003
；
where N =0,1, ·, N-1, K =0,1,. ·, K-1, mod (×) is a modulo operation, j is a complex field, and e is a natural logarithm.
Preferably, the obtaining a channel estimation value based on the pilot data stream specifically includes:
acquiring pseudo pilot frequency data of the IAM-new pilot frequency data and data of the IAM-new pilot frequency data after channel reception;
determining a fixed channel estimation value based on the pseudo pilot frequency data, the IAM-new pilot frequency data and data after the IAM-new pilot frequency data is received by a channel;
determining a discrete pilot frequency estimated value based on data of the discrete pilot frequency data after the data is received by a channel;
and determining the channel estimation value based on the discrete pilot estimation value and the interference value of the adjacent signal in the discrete pilot estimation value.
Preferably, the performing a discrete processing on the channel estimation value to obtain a discrete pilot estimation value specifically includes: the demodulating the channel information to obtain demodulated binary data specifically includes:
and after ZF equalization processing is carried out on the channel information, serial-parallel conversion processing and QAM mapping processing are carried out to obtain demodulated binary data.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects:
the invention provides a pilot frequency method based on OFDM/OQAM under industrial 5G, QAM mapping is carried out on binary bit stream to obtain a QAM data set, then a discrete pilot frequency data is inserted between every L-1 QAM data in the QAM data set to obtain a first data stream, performing serial-to-parallel conversion on the complex data in the first data stream to obtain a second data stream, then placing IAM-new pilot data in front of the second data stream to obtain a pilot data stream, obtaining a channel estimation value based on the pilot data stream, performing discrete processing on the channel estimation value to obtain a discrete pilot estimation value, performing first-order linear interpolation processing on the discrete pilot estimation value based on the channel estimation value to obtain channel information of each column of pilot data stream, demodulating the channel information to obtain a demodulated binary data stream, so as to reduce the BER of the demodulation information of the receiving end and further enhance the robustness of the anti-drop channel of the OFDM/OQAM system.
Corresponding to the pilot method based on OFDM/OQAM under industrial 5G, the invention also provides a pilot system based on OFDM/OQAM under industrial 5G, which comprises:
the data mapping module is used for carrying out QAM mapping on the binary bit stream to obtain a QAM data set;
the data insertion module is used for inserting a scattered pilot frequency data between every L-1 QAM data in the QAM data set to obtain a first data stream; the first data stream is a data matrix with N columns and K rows;
the data conversion module is used for performing serial-parallel conversion on the complex data in the first data stream to obtain a second data stream; the second data stream is a data matrix with K columns and N rows;
the pilot data module is used for placing IAM-new pilot data in front of the second data stream to obtain a pilot data stream;
a channel estimation module, configured to obtain a channel estimation value based on the pilot data stream;
the discrete estimation module is used for performing discrete processing on the channel estimation value to obtain a discrete pilot estimation value;
the interpolation processing module is used for carrying out first-order linear interpolation processing on the discrete pilot frequency estimated value based on the channel estimated value to obtain channel information of each row of pilot frequency data streams;
and the data demodulation module is used for demodulating the channel information to obtain a demodulated binary data stream.
Preferably, the data conversion module includes:
a data conversion unit for adopting the model
Figure 271038DEST_PATH_IMAGE004
Performing serial-parallel conversion on the complex data in the first data stream to obtain conversion data;
wherein D is the second data stream,d 1is the first complex number of data, and the first complex number of data,d 2for the second one of the complex number data,d 3as the third complex number data, the first complex number data,d Kfor the Kth complex data, T is the transpose of the matrix, and each complex data includes N data.
Preferably, the channel estimation module includes:
a data obtaining unit, configured to obtain pseudo pilot data of the IAM-new pilot data and data obtained after the IAM-new pilot data is received through a channel;
a fixed channel estimation unit, configured to determine a fixed channel estimation value based on the pseudo pilot data, the IAM-new pilot data, and data obtained after the IAM-new pilot data is received through a channel;
the pilot frequency point estimation unit is used for determining a pilot frequency point estimation value based on data of the scattered pilot frequency data received by a channel;
and the channel estimation unit is used for determining the channel estimation value based on the pilot point estimated value and the interference value of the adjacent signal in the pilot point estimated value.
Preferably, the data demodulation module includes:
and the data demodulation unit is used for performing ZF equalization processing on the channel information, and then performing serial-parallel conversion processing and QAM mapping processing to obtain demodulated binary data.
The technical effect of the pilot frequency system based on the OFDM/OQAM under the industrial 5G provided by the invention is the same as that of the pilot frequency method based on the OFDM/OQAM under the industrial 5G, so that the detailed description is omitted.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a flowchart of a pilot method based on OFDM/OQAM under industrial 5G according to the present invention;
FIG. 2 is a block diagram of a baseband implementation of OFDM/OQAM;
fig. 3 is a block diagram of pilot insertion according to an embodiment of the present invention;
FIG. 4 is a diagram illustrating simulation results provided by an embodiment of the present invention;
fig. 5 is a schematic structural diagram of a pilot system based on OFDM/OQAM in industrial 5G according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide a pilot frequency method and a pilot frequency system based on OFDM/OQAM under industrial 5G, which can reduce BER of demodulation information of a receiving end and further enhance the robustness of a drop-resistant channel of the OFDM/OQAM system.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
As shown in fig. 1, the pilot method based on OFDM/OQAM under industrial 5G provided by the present invention includes:
step 100: and carrying out QAM mapping on the binary bit stream to obtain a QAM data set. QAM mapping is constellation mapping.
Step 101: a scattered pilot data is inserted between every L-1 QAM data in a QAM data set to obtain a first data stream. The first data stream is a data matrix with N columns and K rows. Assuming that the number of subcarriers is N, L scattered pilot data are inserted into each N-L QAM data to form complex data of L pilots and N-L QAM data, so as to form a first data stream.
Assuming S = N/L, the N data of the 1 st line in the first data stream ared 1：
d 1= j, S-1 data, = [1, S-1 data, j, S-1 data, ], 1, S-1 data, ]]。
N data of line 2 ared 2：
d 2= [1 data, j, S-1 data, -1, S-1 data, -j, S-1 data, 1, S-1 data,..., 1, S-2 data]。
Line 3N data isd 3：
d 3= [2 data, -1, S-1 data, -j, S-1 data, 1, S-1 data, j, S-1 data,..., j, S-3 data]。
By analogy, the K row N data is set asd k 。
Step 102: and performing serial-parallel conversion on the complex data in the first data stream to obtain a second data stream. The second data stream is a data matrix with K columns and N rows. For example, using models
Figure DEST_PATH_IMAGE005
And performing serial-parallel conversion on the complex data in the first data stream to obtain conversion data. The scattered pilot distribution model for the second data stream is:
Figure 459312DEST_PATH_IMAGE006
；
Figure DEST_PATH_IMAGE007
。
wherein D is the second data stream,d 1is the first complex number data, and the first complex number data,d 2for the second one of the complex number data,d 3is the third one of the complex number data,d Kfor the kth complex data, T is the transpose of the matrix, each complex data includes N data, N =0, 1. Each K rows of complex data is a frame, in each frame of complex data, the total quantity of the scattered pilots is N/L K, and the actual transmission data efficiency of each frame is [ (K-1/K +3) × N/N + 1%]B/Hz。
Step 103: and placing the IAM-new pilot data before the second data stream to obtain the pilot data stream. The resulting pilot data stream is 3 columns.
Step 104: a channel estimate is derived based on the pilot data stream. Specifically, the method comprises the following steps:
and acquiring pseudo pilot frequency data of the IAM-new pilot frequency data and data of the IAM-new pilot frequency data after channel reception.
And determining a fixed channel estimation value based on the pseudo pilot frequency data, the IAM-new pilot frequency data and the data after the IAM-new pilot frequency data is received by the channel.
A scattered pilot estimation value is determined based on data of the scattered pilot data received through a channel.
And determining a channel estimation value based on the discrete pilot estimation value and the interference value of the adjacent signal in the discrete pilot estimation value.
Step 105: and carrying out discrete processing on the channel estimation value to obtain a discrete pilot frequency estimation value.
Step 106: and performing first-order linear interpolation processing on the discrete pilot frequency estimated value based on the channel estimated value to obtain channel information of each column of pilot frequency data stream.
Step 107: and demodulating the channel information to obtain a demodulated binary data stream. For example, after ZF equalization processing is performed on the channel information, serial-to-parallel conversion processing and QAM mapping processing are performed to obtain demodulated binary data.
In the implementation, each time a frame of data is transmitted, corresponding scattered pilot and IAM-new pilot data are inserted according to steps 100-103.
An OFDM/OQAM baseband implementation block diagram is shown in fig. 2, where a random data bit stream is generated, QAM mapping is performed, serial-to-parallel conversion is performed, pilot is added, then phase offsets are added to a real part and an imaginary part of data, OFDM modulation is performed, then a Time Frequency aggregation (TFL) function with a good TFL performance by using an Isotropic Orthogonal Transformation Algorithm (IOTA) is added, and finally a baseband transmission signal is formed by entering a channel.
The receiving process is the inverse of the transmitting process and will not be described in more detail here. The equalization may use Zero Forcing (ZF) mode, and the specific simulation parameters are shown in table 1.
Figure 891561DEST_PATH_IMAGE008
The following describes a specific implementation process of the pilot method based on OFDM/OQAM under industrial 5G provided above, taking the generation of 4QAM signal as an example.
Step 1, generating a binary bit stream, and carrying out 4QAM mapping to obtain 4QAM data.
Step 2, inserting 1 scattered pilot into every 31 4QAM data of the data in the step 1, if the number of subcarriers is 2048, inserting 64 scattered pilot data into every 1984 QAM data, and forming complex data of 64 pilots and 1984 QAM data:
the 1 st 2048 complex data is d1：
d 1= 1,31 data, j,31 data, -1,31 data, -j,31 data,. -, j,31 data]。
2048 complex data of the 2 nd row ared 2：
d 2= 1 data, j,31 data, -1,31 data, -j,31 data, 1,31 data,.. 1,30 data]。
2048 complex data of the 3 rd row ared 3：
d 3= [2 numbers ]Data, -1,31 data, -j,31 data, 1,31 data, j,31 data]。
By analogy, the 20 th line 2048 complex data isd k ：
d 20= 19 data, -1,31 data, -j,31 data, 1,31 data, j,31 data,.. j,12 data]。
And 3, performing serial-parallel conversion on the data stream obtained in the step 2, wherein each column of data is 2048, and each 20 columns of data are one frame of data.
The mathematical model for this step 3 is then:
Figure DEST_PATH_IMAGE009
;
suppose that
Figure 532496DEST_PATH_IMAGE010
Mod is a modulo operation, where the number of rows of one frame data is k (k =0,1, 2, …, 19), and the number of rows of data is N (N =0,1, 2.. N-1), the mathematical model of the scattered pilots is:
Figure DEST_PATH_IMAGE011
。
and 4, placing an IAM-new pilot frequency in front of the data D in the step 3 to obtain a 3-column matrix, wherein the 1 st column and the 3 rd column are 0, and the 2 nd column is {1, j, -1, -j,. 1, j, -1, -j }, and the pilot frequency structure is shown in FIG. 3.
Each time one frame of data is transmitted, corresponding scattered pilot and IAM-new pilot are inserted according to steps 1-4.
The OFDM/OQAM adopts Fourier fast algorithm (IFFT and FFT) to reduce the implementation complexity, and adopts the IOTA function to reduce the power of side lobes and improve the robustness of a fast fading channel. And adding the pilot frequency data into the express train A channel model at the same time. The specific steps of this process are not described in detail because of the conventional art.
Step 5, fixing the IAM-new line by utilizing an interference utilization methodThe channel estimation value of the interference part is
Figure 872342DEST_PATH_IMAGE012
。
The IAM-new pilot data has pseudo pilot data ofICI n ：
Figure DEST_PATH_IMAGE013
。
Wherein the content of the first and second substances,P n for the IAM-new pilot data,P n+p adjacent pilot values for the IAM-new pilot data,<g>which is an inner product, is herein understood to be a correlation value between adjacent data.
The fixed channel estimation value obtained by the IAM-new is
Figure 915122DEST_PATH_IMAGE014
：
Figure DEST_PATH_IMAGE015
Wherein, in the step (A),
Figure 518273DEST_PATH_IMAGE016
is the result after the IAM-new pilot data is received through the channel.
Step 6: channel estimation values obtained using scattered pilots
Is provided withnIs the number of sub-carriers (value range 0-2047),kfor the number of columns of the signal where scattered pilots are mixed with 4QAM (ranging from 0 to 19), the predicted value of the (scattered) pilot point is
Figure DEST_PATH_IMAGE017
：
Figure 652363DEST_PATH_IMAGE018
，
Figure DEST_PATH_IMAGE019
For nodes after scattered pilot data has been received via the channelAnd (5) fruit.
The scattered pilot estimation has Interference value of adjacent signals, i.e. imaginary Interference (IRS), and Real channel estimation value
Figure 264741DEST_PATH_IMAGE020
Subtract IRS for the estimate, expressed as:
Figure DEST_PATH_IMAGE021
wherein, in the step (A),qthe column number in the parallel data, p the row number in the parallel data,
Figure 427607DEST_PATH_IMAGE022
for data values adjacent to the receiving end data,
Figure DEST_PATH_IMAGE023
for the channel estimation values adjacent to the current channel estimation value,
Figure 263976DEST_PATH_IMAGE024
is the inner product value of the filter at the receiving end.
And 7: and performing first-order linear interpolation on the channel estimation result of the scattered pilot frequency to obtain:
Figure DEST_PATH_IMAGE025
wherein, in the step (A),
Figure 161393DEST_PATH_IMAGE026
in order for the data to be interpolated to be,
Figure DEST_PATH_IMAGE027
is a channel estimate of the pilot position,iis the data sequence number between adjacent pilots.
Thus, the channel information of each column of pilot frequency can be obtained, and the fast change part in the channel can be estimated.
And performing ZF equalization on the estimated data information, then performing serial-parallel conversion and QAM inverse mapping to obtain demodulated binary data, wherein the BER simulation result is P-COMBINE. The invention analyzes the effectiveness (actual transmission rate of data) and the reliability (BER) by calculating the computational complexity and the engineering realizability.
(1) Effectiveness of
For the simulation parameters, the IOTA function is used, the number of taps is 4N of the number of subcarriers, and the effective data transmission rate is as follows: η =20/27= 74.1%.
The IOTA is 4 taps, which results in 3N data, the block pilot needs 3N data, and the scattered pilot has N data. The effective data transmission rates of the present invention, OFDM-CP and IAM-new are shown in Table 2.
Figure 764413DEST_PATH_IMAGE028
As can be seen from Table 2, the effective transmission rate of OFDM/CP is the highest, and the invention is the lowest.
(2) BER performance comparison
From the reliability, the present invention performs better than OFDM/CP and IAM-new, as shown in fig. 4, when BER =2 x 10-3Next, the present invention (P-COMBINE) has 2dB less energy than OFDM/CP compared to IAM-new.
(3) Complexity of calculation
As shown in table 3, the computational complexity of the present invention focuses on interference cancellation of adjacent channels, and the multiplicative and additive complexity is proportional to the number of subcarriers and the length.
Figure DEST_PATH_IMAGE029
The invention estimates the fixed interference part of the channel by using the IAM-new block pilot frequency, and further eliminates the fast change part of the channel by designing the discrete pilot frequency. The effectiveness of the design of the invention is verified through simulation by sacrificing a certain amount of effective information transmission rate and calculation complexity.
Based on this, the design method of the invention is divided into a scattered pilot design and a block pilot design, the design idea is that aiming at the time-varying fast fading channel, the block pilot aims at the inherent channel interference part in the time-varying channel, and the inherent interference part of the channel frequency domain response can be obtained by utilizing the characteristic of the maximum pseudo pilot power. The design of the discrete pilot frequency of the invention is to utilize the current information to estimate the burst interference or random interference in the time domain and the frequency domain of the channel part to obtain the fast changing part of the channel, aiming at the changing condition of the channel, the insertion quantity of the discrete pilot frequency needs to be adjusted in time to obtain the estimated value of the channel, and at the demodulation end, the quality of the received information can be improved.
Corresponding to the above-mentioned pilot method based on OFDM/OQAM under industrial 5G, the present invention also provides a pilot system based on OFDM/OQAM under industrial 5G, as shown in fig. 5, the system includes:
and the data mapping module 500 is configured to perform QAM mapping on the binary bit stream to obtain a QAM data set.
A data inserting module 501, configured to insert a scattered pilot data between every L-1 QAM data in a QAM data set to obtain a first data stream. The first data stream is a data matrix with N columns and K rows.
The data conversion module 502 is configured to perform serial-to-parallel conversion on the complex data in the first data stream to obtain a second data stream. The second data stream is a data matrix with K columns and N rows.
A pilot data module 503, configured to put IAM-new pilot data before the second data stream to obtain a pilot data stream.
A channel estimation module 504, configured to obtain a channel estimation value based on the pilot data stream.
A discrete estimation module 505, configured to perform discrete processing on the channel estimation value to obtain a discrete pilot estimation value.
And an interpolation processing module 506, configured to perform first-order linear interpolation on the discrete pilot estimation values based on the channel estimation values to obtain channel information of each column of pilot data streams.
And a data demodulation module 507, configured to demodulate the channel information to obtain a demodulated binary data stream.
As a preferred embodiment of the present invention, the data conversion module 502 adopted above includes:
a data conversion unit for adopting the model
Figure 329255DEST_PATH_IMAGE030
And performing serial-parallel conversion on the complex data in the first data stream to obtain conversion data.
Wherein D is the second data stream,d 1is the first complex number data, and the first complex number data,d 2for the second one of the complex number data,d 3as the third complex number data, the first complex number data,d Kt is the transpose of the matrix for the Kth complex data, each complex data comprising N data.
As another preferred embodiment of the present invention, the channel estimation module 504 adopted above includes:
and the data acquisition unit is used for acquiring the pseudo pilot frequency data of the IAM-new pilot frequency data and the data of the IAM-new pilot frequency data after the IAM-new pilot frequency data is received by a channel.
And the fixed channel estimation unit is used for determining a fixed channel estimation value based on the pseudo pilot frequency data, the IAM-new pilot frequency data and the data after the IAM-new pilot frequency data is received by the channel.
And the pilot point estimation unit is used for determining a pilot point estimation value based on the data of the scattered pilot data received by the channel.
And the channel estimation unit is used for determining a channel estimation value based on the pilot point estimated value and the interference value of the adjacent signal in the pilot point estimated value.
As another preferred embodiment of the present invention, the data demodulation module adopted above includes:
and the data demodulation unit is used for performing ZF equalization processing on the channel information, and then performing serial-parallel conversion processing and QAM mapping processing to obtain demodulated binary data.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. For the system disclosed by the embodiment, the description is relatively simple because the system corresponds to the method disclosed by the embodiment, and the relevant points can be referred to the method part for description.
The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims (9)

1. A pilot method based on OFDM/OQAM under industrial 5G is characterized by comprising the following steps:
carrying out QAM mapping on the binary bit stream to obtain a QAM data set;
inserting a discrete pilot frequency data between every L-1 QAM data in the QAM data set to obtain a first data stream; the first data stream is a data matrix with N columns and K rows;
performing serial-parallel conversion on the complex data in the first data stream to obtain a second data stream; the second data stream is a data matrix with K columns and N rows;
placing IAM-new pilot frequency data in front of the second data flow to obtain a pilot frequency data flow;
obtaining a channel estimation value based on the pilot data stream;
performing discrete processing on the channel estimation value to obtain a discrete pilot frequency estimation value;
performing first-order linear interpolation processing on the discrete pilot frequency estimated value based on the channel estimated value to obtain channel information of each row of pilot frequency data streams;
and demodulating the channel information to obtain a demodulated binary data stream.
2. The industrial 5G-based pilot method for OFDM/OQAM according to claim 1, wherein the performing serial-to-parallel conversion on the complex data in the first data stream to obtain a second data stream specifically comprises:
using a model
Figure DEST_PATH_IMAGE001
Performing serial-parallel conversion on the complex data in the first data stream to obtain conversion data;
wherein D is the second data stream,d 1is the first complex number data, and the first complex number data,d 2for the second one of the complex number data,d 3as the third complex number data, the first complex number data,d Kfor the Kth complex data, T is the transpose of the matrix, and each complex data includes N data.
3. The industrial 5G OFDM/OQAM-based pilot method as claimed in claim 2, wherein the scattered pilot distribution model of the second data stream is:
Figure 550396DEST_PATH_IMAGE002
；
Figure DEST_PATH_IMAGE003
；
where N =0,1, ·, N-1, K =0,1,. ·, K-1, mod (×) is a modulo operation, j is a complex field, and e is a natural logarithm.
4. The industrial 5G OFDM/OQAM-based pilot method according to claim 1, wherein the obtaining of the channel estimation value based on the pilot data stream specifically comprises:
acquiring pseudo pilot frequency data of the IAM-new pilot frequency data and data of the IAM-new pilot frequency data after channel reception;
determining a fixed channel estimation value based on the pseudo pilot frequency data, the IAM-new pilot frequency data and data after the IAM-new pilot frequency data is received by a channel;
determining a discrete pilot frequency estimated value based on data after the discrete pilot frequency data is received by a channel;
and determining the channel estimation value based on the discrete pilot estimation value and the interference value of the adjacent signal in the discrete pilot estimation value.
5. The pilot method based on OFDM/OQAM in industrial 5G according to claim 1, wherein the discretizing the channel estimation value to obtain a discretized pilot estimation value specifically comprises: the demodulating the channel information to obtain demodulated binary data specifically includes:
and after ZF equalization processing is carried out on the channel information, serial-parallel conversion processing and QAM mapping processing are carried out to obtain demodulated binary data.
6. A pilot system based on OFDM/OQAM under industrial 5G, comprising:
the data mapping module is used for carrying out QAM mapping on the binary bit stream to obtain a QAM data set;
the data insertion module is used for inserting a scattered pilot frequency data between every L-1 QAM data in the QAM data set to obtain a first data stream; the first data stream is a data matrix with N columns and K rows;
the data conversion module is used for performing serial-parallel conversion on the complex data in the first data stream to obtain a second data stream; the second data stream is a data matrix with K columns and N rows;
the pilot frequency data module is used for placing IAM-new pilot frequency data in front of the second data stream to obtain a pilot frequency data stream;
a channel estimation module, configured to obtain a channel estimation value based on the pilot data stream;
the discrete estimation module is used for performing discrete processing on the channel estimation value to obtain a discrete pilot estimation value;
the interpolation processing module is used for carrying out first-order linear interpolation processing on the discrete pilot frequency estimated value based on the channel estimated value to obtain channel information of each row of pilot frequency data streams;
and the data demodulation module is used for demodulating the channel information to obtain a demodulated binary data stream.
7. The pilot system of claim 6, wherein the data conversion module comprises:
a data conversion unit for adopting the model
Figure 608482DEST_PATH_IMAGE004
Performing serial-parallel conversion on the complex data in the first data stream to obtain conversion data;
wherein D is the second data stream,d 1is the first complex number data, and the first complex number data,d 2for the second one of the complex number data,d 3as the third complex number data, the first complex number data,d Kfor the Kth complex data, T is the transpose of the matrix, and each complex data includes N data.
8. The industrial 5G OFDM/OQAM based pilot system as claimed in claim 6, wherein said channel estimation module comprises:
a data obtaining unit, configured to obtain pseudo pilot data of the IAM-new pilot data and data obtained after the IAM-new pilot data is received through a channel;
a fixed channel estimation unit, configured to determine a fixed channel estimation value based on the pseudo pilot data, the IAM-new pilot data, and data obtained after the IAM-new pilot data is received through a channel;
the pilot frequency point estimation unit is used for determining a pilot frequency point estimation value based on data of the scattered pilot frequency data received by a channel;
and the channel estimation unit is used for determining the channel estimation value based on the pilot point estimated value and the interference value of the adjacent signal in the pilot point estimated value.
9. The industrial 5G OFDM/OQAM based pilot system as claimed in claim 6, wherein said data demodulation module comprises:
and the data demodulation unit is used for performing ZF equalization processing on the channel information, and then performing serial-parallel conversion processing and QAM mapping processing to obtain demodulated binary data.
CN202210417445.4A 2022-04-21 2022-04-21 Pilot frequency method and system based on OFDM/OQAM under industrial 5G Active CN114513396B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210417445.4A CN114513396B (en) 2022-04-21 2022-04-21 Pilot frequency method and system based on OFDM/OQAM under industrial 5G

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210417445.4A CN114513396B (en) 2022-04-21 2022-04-21 Pilot frequency method and system based on OFDM/OQAM under industrial 5G

Publications (2)

Publication Number Publication Date
CN114513396A true CN114513396A (en) 2022-05-17
CN114513396B CN114513396B (en) 2022-07-08

Family

ID=81555014

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210417445.4A Active CN114513396B (en) 2022-04-21 2022-04-21 Pilot frequency method and system based on OFDM/OQAM under industrial 5G

Country Status (1)

Country Link
CN (1) CN114513396B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115118558A (en) * 2022-08-22 2022-09-27 北京科技大学 Self-interference elimination method and system for OFDM/OQAM in mobile communication

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006117268A1 (en) * 2005-05-03 2006-11-09 France Telecom Method for the iterative decoding of an ofdm/oqam signal using symbols with complex values, and corresponding device and computer program
CN102273113A (en) * 2009-01-08 2011-12-07 夏普株式会社 Transmitter apparatus, transmission method, communication system and communication method
CN104506467A (en) * 2014-12-31 2015-04-08 上海交通大学 Channel estimation method for improving receiving sensitivity of OQAM (Offset Quadrate Amplitude Modulation)-OFDM (Orthogonal Frequency Division Multiplexing) light transmission system
CN106888178A (en) * 2017-03-29 2017-06-23 桂林电子科技大学 A kind of OFDM/OQAM system channel estimation methods
CN107438038A (en) * 2017-06-07 2017-12-05 西安交通大学 A kind of FBMC/OQAM pilot design and synchronization channel estimation method
CN109167744A (en) * 2018-11-06 2019-01-08 上海事凡物联网科技有限公司 A kind of phase noise combined estimation method
CN113300995A (en) * 2021-06-08 2021-08-24 西安邮电大学 Channel estimation algorithm for IM/DD-OFDM/OQAM-PON system

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006117268A1 (en) * 2005-05-03 2006-11-09 France Telecom Method for the iterative decoding of an ofdm/oqam signal using symbols with complex values, and corresponding device and computer program
CN102273113A (en) * 2009-01-08 2011-12-07 夏普株式会社 Transmitter apparatus, transmission method, communication system and communication method
CN104506467A (en) * 2014-12-31 2015-04-08 上海交通大学 Channel estimation method for improving receiving sensitivity of OQAM (Offset Quadrate Amplitude Modulation)-OFDM (Orthogonal Frequency Division Multiplexing) light transmission system
CN106888178A (en) * 2017-03-29 2017-06-23 桂林电子科技大学 A kind of OFDM/OQAM system channel estimation methods
CN107438038A (en) * 2017-06-07 2017-12-05 西安交通大学 A kind of FBMC/OQAM pilot design and synchronization channel estimation method
CN109167744A (en) * 2018-11-06 2019-01-08 上海事凡物联网科技有限公司 A kind of phase noise combined estimation method
CN113300995A (en) * 2021-06-08 2021-08-24 西安邮电大学 Channel estimation algorithm for IM/DD-OFDM/OQAM-PON system

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
孙希东: "OFDM/OQAM系统在瑞利信道下的信道估计与均衡方法", 《自动化技术与应用》 *
张凯等: "基于压缩感知的OQAM/OFDM系统POP方法信道估计", 《测控技术》 *
陈西宏等: "OQAM/OFDM中基于干扰消除的插值信道估计", 《探测与控制学报》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115118558A (en) * 2022-08-22 2022-09-27 北京科技大学 Self-interference elimination method and system for OFDM/OQAM in mobile communication
CN115118558B (en) * 2022-08-22 2022-11-08 北京科技大学 Self-interference elimination method and system for OFDM/OQAM in mobile communication

Also Published As

Publication number Publication date
CN114513396B (en) 2022-07-08

Similar Documents

Publication Publication Date Title
Colieri et al. A study of channel estimation in OFDM systems
JP4472771B2 (en) Receiver for receiving a multicarrier signal
Ghauri et al. Implementation of OFDM and channel estimation using LS and MMSE estimators
CN101136884B (en) Channel estimation method for TDS-OFDM system
CN103227768B (en) The application in OFDM modulates of a kind of new ICI self elimination method
CN107770110A (en) A kind of sending method of discontinuous frame, channel compensating method
CN111600816A (en) Two-dimensional interpolation channel estimation method for power line carrier communication
CN107483373A (en) A kind of the LMMSE channel estimation methods and device of the weighting of anti-multipath iteration
CN114513396B (en) Pilot frequency method and system based on OFDM/OQAM under industrial 5G
Zhou et al. Channel Estimation Based on Linear Filtering Least Square in OFDM Systems.
CN109861939B (en) OQPSK frequency domain equalization wireless data transmission method
CN100477651C (en) High-performance OFDM channel estimation method based on combined pilot
Al-Susa et al. A predictor-based decision feedback channel estimation method for COFDM with high resilience to rapid time-variations
Al-Gharabally et al. On the performance of OFDM systems in time varying channels with channel estimation error
Harbi et al. Wiener filter channel estimation for OFDM/OQAM with iterative interference cancellation in LTE channel
KR101294283B1 (en) Method for estimating channel based on cross correlation of ofdm system and device thereof
Khan et al. A novel channel estimation error minimizing interpolation technique for OFDM systems
Khadagade et al. Comparison of BER of OFDM system using QPSK and 16QAM over multipath Rayleigh fading channel using pilot-based channel estimation
WO2014037321A1 (en) Method and device for improving a home network making use of an adaptive guard interval
CN103414667A (en) OFDM self-adaptive channel estimation method based on two-dimensional scattered pilot frequencies
CN115118558B (en) Self-interference elimination method and system for OFDM/OQAM in mobile communication
Ahmed et al. Semi-adaptive channel estimation technique for LTE systems
Zhang et al. Research on pilot-aided channel estimation techniques in OFDM system
Yang et al. Channel estimation for the Chinese DTTB system based on a novel iterative PN sequence reconstruction
KR101131494B1 (en) Method for doppler frequency estimation and receiver for doppler frequency estimation for ofdm system

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
GR01 Patent grant
GR01 Patent grant