CN113965441B - Radar communication integrated signal generation and receiving method based on random step frequency OFDM - Google Patents

Radar communication integrated signal generation and receiving method based on random step frequency OFDM Download PDF

Info

Publication number
CN113965441B
CN113965441B CN202111220945.0A CN202111220945A CN113965441B CN 113965441 B CN113965441 B CN 113965441B CN 202111220945 A CN202111220945 A CN 202111220945A CN 113965441 B CN113965441 B CN 113965441B
Authority
CN
China
Prior art keywords
pulse
sequence
symbol
signal
step frequency
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.)
Active
Application number
CN202111220945.0A
Other languages
Chinese (zh)
Other versions
CN113965441A (en
Inventor
张贞凯
王小江
靳标
尚尚
奚彩萍
苏胤杰
练柱先
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.)
Jiangsu University of Science and Technology
Original Assignee
Jiangsu University of Science and Technology
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 Jiangsu University of Science and Technology filed Critical Jiangsu University of Science and Technology
Priority to CN202111220945.0A priority Critical patent/CN113965441B/en
Priority to PCT/CN2021/126142 priority patent/WO2023065374A1/en
Priority to KR1020227040030A priority patent/KR20230058008A/en
Publication of CN113965441A publication Critical patent/CN113965441A/en
Application granted granted Critical
Publication of CN113965441B publication Critical patent/CN113965441B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

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
    • 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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/06—Systems determining position data of a target
    • G01S13/08—Systems for measuring distance only
    • G01S13/32—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
    • G01S13/34—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
    • G01S13/341—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal wherein the rate of change of the transmitted frequency is adjusted to give a beat of predetermined constant frequency, e.g. by adjusting the amplitude or frequency of the frequency-modulating signal
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/50—Systems of measurement based on relative movement of target
    • G01S13/52—Discriminating between fixed and moving objects or between objects moving at different speeds
    • G01S13/536—Discriminating between fixed and moving objects or between objects moving at different speeds using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/28—Details of pulse systems
    • G01S7/282—Transmitters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/28—Details of pulse systems
    • G01S7/285—Receivers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J13/00—Code division multiplex systems
    • H04J13/0007—Code type
    • H04J13/0055—ZCZ [zero correlation zone]
    • H04J13/0059—CAZAC [constant-amplitude and zero auto-correlation]
    • H04J13/0062—Zadoff-Chu
    • 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
    • H04L27/2614—Peak power aspects
    • 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
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2649—Demodulators
    • H04L27/26534—Pulse-shaped multi-carrier, i.e. not using rectangular window

Abstract

The application discloses a radar communication integrated signal generation and receiving method based on random step frequency OFDM, which comprises the following steps: generating radar communication integrated signals: modulating the step frequency of each pulse in each symbol of the first pulse; modulating user information to be communicated in a corresponding symbol of the second pulse; modulating the communication information in the third to last pulses; up-converting the baseband signal of each pulse according to the step frequency and transmitting the signal; receiving radar communication integrated signals: down-converting the first pulse and demodulating the first pulse to obtain the step frequency of each pulse; performing down-conversion on the second pulse according to the step frequency and demodulating to obtain user information; and carrying out down-conversion on the third to last pulses according to the step frequency and demodulating to obtain communication information. The application can realize point-to-multipoint communication in the radar communication integrated system and realize confidentiality communication in a special system by utilizing the random step frequency of each pulse.

Description

Radar communication integrated signal generation and receiving method based on random step frequency OFDM
Technical Field
The application belongs to the technical field of radar communication integration, and particularly relates to a radar communication integration signal generation and communication receiving method based on random step frequency OFDM.
Background
The radar communication integrated (Integration ofRadar and Communications, IRC) system realizes radar detection and wireless communication functions at the transmitting end and the receiving end, and has great advantages, such as improving the frequency spectrum utilization rate and the frequency spectrum resource utilization rate, and becomes a hot spot for research in recent years. The radar communication integrated system is widely applied to wireless radar sensor networks, indoor positioning and activity recognition, unmanned aerial vehicle monitoring, internet of vehicles and other systems. Radar communication integrated systems typically employ pulsed communication signals to simultaneously implement detection and communication functions.
Orthogonal frequency division multiplexed (Orthogonal Frequency Division Modulation, OFDM) signals have many excellent characteristics and are thus applied to radar and communication systems. The communication characteristics mainly include high frequency band utilization and multipath resistance, and the radar characteristics mainly include high range resolution and range-free doppler coupling. The pulsed OFDM communication signal is an integrated signal that is often used by radar communication integrated systems. The random step frequency signal can synthesize the instant narrow bandwidth signal into an effective large bandwidth signal, and the distance resolution is improved. In an airborne radar communication integrated system, a signal transmission technology is needed to realize point-to-multipoint and confidentiality communication, and the prior art cannot realize the requirements.
Disclosure of Invention
The application aims to: in order to overcome the defects in the prior art, the radar communication integrated signal generation and communication receiving method based on the random step frequency OFDM is provided, and multi-user and confidentiality communication of the radar communication integrated system can be ensured.
The technical scheme is as follows: in order to achieve the above object, the present application provides a radar communication integrated signal generating and receiving method based on random step frequency OFDM, including the steps of:
the specific generation method for generating the radar communication integrated signal comprises the following steps:
a1: modulating the step frequency of the random step frequency OFDM radar communication integrated baseband signal in each pulse in each symbol of the first pulse;
a2: modulating user information to be communicated in a corresponding symbol of the second pulse;
a3: modulating the communication information in the third to last pulses;
a4: up-converting the baseband signal of each pulse according to the step frequency and transmitting the signal;
the specific receiving method for receiving the radar communication integrated signal comprises the following steps:
b1: down-converting the first pulse and demodulating the first pulse to obtain the step frequency of each pulse;
b2: performing down-conversion on the second pulse according to the step frequency and demodulating to obtain user information;
b3: and carrying out down-conversion on the third to last pulses according to the step frequency and demodulating to obtain communication information.
Further, the expression of the random step frequency OFDM radar communication integrated baseband signal in the step A1 is:
wherein N is p In order to provide the number of pulses, p=0, 1,.. p -1；N s For the number of symbols, m=0, 1, …, N s -1；N c N=0, 1, …, N as the number of subcarriers c -1; c (n, m, p) is communication modulation information of the p-th pulse, the m-th symbol and the n-th subcarrier, Δf is a subcarrier frequency interval, and t=1/Δf is a time width of the OFDM symbol; t (T) cp Is the time width of the cyclic prefix, T s ＝T cp +T is the time bandwidth of the complete OFDM symbol; t (T) p Is a pulse repetition period; rect (t) is a window function, only when t.epsilon.0, 1]And its value is 1 when it is, otherwise, its value is 0.
Further, in the step A1, for c (n, m, p), different ZC (Zadoff-Chu) sequences are adopted as modulation information of subcarriers in different symbols.
The step A1 specifies N s ＝N p And, the number of ZC sequences is defined as N zc The number of sequences and the number of pulses need to satisfy N zc ＞N p The method comprises the steps of carrying out a first treatment on the surface of the Specifying the length N of ZC sequence k ＝N c -1, varying the parameter μ generates N zc ZC sequences, the length of which is extended to N by zero padding c And is used as modulation information of different subcarriers in one symbol; for N zc Numbering the ZC sequences to obtainAnd zc=0, 1,.. zc -1；
Step frequency d of each pulse p Is 0 to N p Random number between-1, number and step frequency d of the p-th pulse p Equal ZC sequence as N of the mth symbol in the first pulse c Modulation information of the sub-carriers, and p=m=zc, to which the step frequency of each pulse is modulated in each symbol of the first pulse. In order to obtain the step frequency of different pulses at the communication receiving end, d is required 0 ＝0。
The step A2 specifically comprises the following steps: in order to implement point-to-multipoint communication in a radar communication integrated system, user information needs to be carried in an integrated signal. Specifying the number of users in the system as N u The number of users and the number of symbols need to satisfy N u ≤N s Stipulating N u ＝N s For N u Numbering the users to obtainAnd u=0, 1,. -%, N u -1, taking the ZC sequence with the same number as the number of the user to be communicated as N of the mth symbol in the second pulse c Modulation information of the sub-carriers, and u=m=zc, up to which the user information to be communicated is modulated in the corresponding symbol of the second pulse.
User information not requiring communication is not modulated in the corresponding symbol of the second pulse, and an alternate sequence is required as N of the symbol c Modulation information of sub-carriers, the sequence being numberedTherefore, the number of sequences and the number of users need to satisfy N zc ＞N u Due to N u ＝N s ，N s ＝N p ，N zc ＞N p Therefore, this condition is easily satisfied. In practice, there isIn the case where multiple users do not need to communicate, there is thus N for multiple symbols in the second pulse c The modulation information of the sub-carrier is a replacement sequence.
Further, the step B1 specifically includes: since the carrier frequency of the first pulse is known to be f c +d 0 B and d 0 =0, down-converting the first pulse at the communication receiving end to obtain a baseband receiving signal, demodulating the baseband receiving signal to obtain ZC sequences in each symbol, and obtaining the number of the ZC sequences in each symbol by looking up a table, namely, the step frequency of each pulse.
Further, the step B2 specifically includes:
step B1 obtains the step frequency d of the second pulse 1 With carrier frequency f c +d 1 B, performing down-conversion on the second pulse at the communication receiving end to obtain a baseband receiving signal, and demodulating the baseband receiving signal to obtain a ZC sequence in each symbol; numbered U u Is numbered ZC zc And the demodulation sequence in the mth symbol is subjected to correlation operation, and u=zc=m, and whether the user is a communicated user is judged according to the operation result.
Further, the method for judging the user to be communicated in the step B2 is as follows:
judging 2Nk-1 amplitude values of the obtained normalized correlation sequence, if only one amplitude value is larger than 0.5, indicating that the obtained sequence is an autocorrelation sequence, and the sequence carried by the mth symbol and the ZC sequence with the same number as the user are the same sequence, wherein the user is a communicated user and needs to continuously receive an integrated signal; if two or more than two amplitude values are larger than 0.5, the obtained sequence is a cross-correlation sequence, the sequence carried by the mth symbol is a replacement sequence, the user is not a communication user, and the integrated signal does not need to be continuously received.
The beneficial effects are that: compared with the prior art, the method has the advantages that the ZC sequence is used as modulation information, so that the low peak-to-average power ratio characteristic of the OFDM radar communication integrated signal and the high peak side lobe ratio characteristic of the fuzzy function of the OFDM radar communication integrated signal are ensured; by carrying user information, point-to-multipoint communication in the radar communication integrated system is realized; by the randomness of the carrier frequency of each pulse, confidentiality communication in a special environment is realized.
Drawings
FIG. 1 is a flow chart of the method of the present application;
FIG. 2 is a schematic diagram of a signal model of the integration of random step frequency OFDM radar communication;
FIG. 3 is a graph of the ZC sequence autocorrelation function of length 31;
fig. 4 is a graph of ZC sequence cross correlation function of length 31.
Detailed Description
The present application is further illustrated in the accompanying drawings and detailed description which are to be understood as being merely illustrative of the application and not limiting of its scope, and various modifications of the application, which are equivalent to those skilled in the art upon reading the application, will fall within the scope of the application as defined in the appended claims.
The application provides a radar communication integrated signal generation and receiving method based on random step frequency OFDM, which comprises two parts of radar communication integrated signal generation and radar communication integrated signal reception, as shown in figure 1, and comprises the following steps:
1. the specific generation method for generating the radar communication integrated signal comprises the following steps:
a1: modulating the step frequency of the random step frequency OFDM radar communication integrated baseband signal in each pulse in each symbol of the first pulse:
the expression of the random step frequency OFDM radar communication integrated baseband signal is as follows:
wherein N is p In order to provide the number of pulses, p=0, 1,.. p -1；N s For the number of symbols, m=0, 1, …, N s -1；N c N=0, 1, …, N as the number of subcarriers c -1; c (n, m, p) is the communication tone of the p-th pulse, m-th symbol, n-th subcarrierInformation is prepared, Δf is a subcarrier frequency interval, and t=1/Δf is a time width of an OFDM symbol; t (T) cp Is the time width of the cyclic prefix, T s ＝T cp +T is the time bandwidth of the complete OFDM symbol; t (T) p Is a pulse repetition period; rect (t) is a window function, only when t.epsilon.0, 1]And its value is 1 when it is, otherwise, its value is 0.
The communication modulation information c (n, m, p) is determined by the information to be transmitted, and thus has randomness, and affects the peak sidelobe ratio performance of the integrated signal blurring function, and further affects the distance and speed detection performance of the integrated signal. In order to ensure peak sidelobe ratio, different ZC sequences are adopted as modulation information of subcarriers in different symbols, and the Fourier invariance, low peak-to-average power ratio characteristic, the distance and speed dimension high peak sidelobe ratio characteristic of an OFDM signal fuzzy function modulated by the ZC sequences and the good autocorrelation and cross-correlation characteristic of the ZC sequences are mainly utilized.
The expression for generating the ZC sequence is:
wherein N is k For the length of the sequence, k=0, 1,.. k -1; mu needs to satisfy mu and N k The greatest common divisor of (2) is 1, two ZC sequences with the same mu are mutually orthogonal, and two ZC sequences with different mu do not have orthogonality; cf is N k The remainder of division by 2; q.epsilon.Z is a parameter.
Each symbol in the first pulse of the integrated signal carries the step frequency of each pulse, so the number of symbols and the number of pulses need to satisfy N s ≥N p The present embodiment specifies N s ＝N p . And, the number of ZC sequences is defined as N zc The number of sequences and the number of pulses need to satisfy N zc ＞N p . We specify the length N of ZC sequence k ＝N c -1, varying the parameter μ generates N zc ZC sequences, the length of which is extended to N by zero padding c And serves as modulation information for different subcarriers in one symbol. For N zc ZC sequencesNumbering to obtainAnd zc=0, 1,.. zc -1。
Step frequency d of each pulse p Is 0 to N p -a random number between 1. Step frequency d of numbering and p-th pulse p Equal ZC sequence as N of the mth symbol in the first pulse c Modulation information of the sub-carriers, and p=m=zc, to which the step frequency of each pulse is modulated in each symbol of the first pulse. In order to obtain the step frequency of different pulses at the communication receiving end, d is required 0 ＝0。
A2: modulating the user information to be communicated in the corresponding symbol of the second pulse:
in order to implement point-to-multipoint communication in a radar communication integrated system, user information needs to be carried in an integrated signal. Specifying the number of users in the system as N u The number of users and the number of symbols need to satisfy N u ≤N s Stipulating N u ＝N s For N u Numbering the users to obtainAnd u=0, 1,. -%, N u -1, taking the ZC sequence with the same number as the number of the user to be communicated as N of the mth symbol in the second pulse c Modulation information of the sub-carriers, and u=m=zc, up to which the user information to be communicated is modulated in the corresponding symbol of the second pulse.
User information not requiring communication is not modulated in the corresponding symbol of the second pulse, and an alternate sequence is required as N of the symbol c Modulation information of sub-carriers, the sequence being numberedTherefore, the number of sequences and the number of users need to satisfy N zc ＞N u Due to N u ＝N s ，N s ＝N p ，N zc ＞N p Therefore, this condition is easily satisfied. In practice, there are situations where multiple users do not need to communicate, so there is N for multiple symbols in the second pulse c The modulation information of the sub-carrier is a replacement sequence.
A3: modulating the communication information in the third to last pulses:
get order 2 l ＜N zc Maximum value of l established, dividing binary communication information into each l and converting into 2 l A binary number for modulating ZC sequences with the same numbers as the conversion values in the third to last N p N of 2 pulses s (N p -2) symbols.
A4: up-converting the baseband signal of each pulse according to the step frequency and transmitting the signal:
up-converting the baseband signal to obtain an integrated transmitting signal, wherein the expression is:
wherein f p Is the carrier frequency of the p-th pulse, and f p ＝f c +d p B，f c As the base carrier frequency, b=n c Δf is the signal bandwidth. The model of the integrated transmission signal of the random step frequency OFDM radar communication is specifically shown in fig. 2.
2. The specific receiving method for receiving the radar communication integrated signal comprises the following steps:
b1: down-converting the first pulse and demodulating to obtain the step frequency of each pulse:
since the carrier frequency of the first pulse is known to be f c +d 0 B and d 0 =0, down-converting the first pulse at the communication receiving end to obtain a baseband receiving signal, demodulating the baseband receiving signal to obtain ZC sequences in each symbol, and obtaining the number of the ZC sequences in each symbol by looking up a table, namely, the step frequency of each pulse.
B2: and carrying out down-conversion on the second pulse according to the step frequency and demodulating to obtain user information:
step B1 obtains the step frequency d of the second pulse 1 With carrier frequency f c +d 1 And B, performing down-conversion on the second pulse at the communication receiving end to obtain a baseband receiving signal, and demodulating the baseband receiving signal to obtain the ZC sequence in each symbol. Numbered U u Is numbered ZC zc And the demodulation sequence in the mth symbol is subjected to correlation operation, and u=zc=m, and whether the user is a communicated user is judged according to the operation result.
The expression of the correlation function of the two sequences is:
wherein i= -N k +1，...，0，...，N k -1, the length of the resulting correlation sequence is 2N k -1；(·) * Representing a conjugate operation. When the two sequences are identical, the expression is an autocorrelation function, otherwise, the expression is a cross correlation function. Normalized auto-and cross-correlation sequences are shown in fig. 3 and 4.
Judging 2N of the obtained normalized correlation sequence k -1 amplitude, if only one amplitude is greater than 0.5, indicating that the obtained sequence is an autocorrelation sequence, the sequence carried by the mth symbol and the ZC sequence with the same number as the user are the same sequence, the user is the user to be communicated, and the integrated signal needs to be continuously received; if two or more than two amplitude values are larger than 0.5, the obtained sequence is a cross-correlation sequence, the sequence carried by the mth symbol is a replacement sequence, the user is not a communication user, and the integrated signal does not need to be continuously received.
B3: down-converting the third to last pulses according to the step frequency and demodulating to obtain communication information:
step B1 obtains the step frequency d of the third to last pulses p With carrier frequency f c +d p B, the user to be communicated down-converts the third to last pulses to obtain a baseband receiving signal, and then the baseband receiving signal is processedThe numbers are demodulated to obtain ZC sequences in each symbol, and the numbers of the ZC sequences in each symbol are obtained through table lookup. Will 2 l The numbering of the bins is converted into l bins and N p N of 2 pulses s (N p -2) combining the binary numbers in the symbols to obtain the communication information.

Claims (2)

1. The radar communication integrated signal generating and receiving method based on the random step frequency OFDM is characterized by comprising the following steps of:
the specific generation method for generating the radar communication integrated signal comprises the following steps:
a1: modulating the step frequency of the random step frequency OFDM radar communication integrated baseband signal in each pulse in each symbol of the first pulse;
a2: modulating user information to be communicated in a corresponding symbol of the second pulse;
a3: modulating the communication information in the third to last pulses;
a4: up-converting the baseband signal of each pulse according to the step frequency and transmitting the signal;
the specific receiving method for receiving the radar communication integrated signal comprises the following steps:
b1: down-converting the first pulse and demodulating the first pulse to obtain the step frequency of each pulse;
b2: performing down-conversion on the second pulse according to the step frequency and demodulating to obtain user information;
b3: down-converting the third to last pulses according to the step frequency and demodulating the third to last pulses to obtain communication information;
the expression of the random step frequency OFDM radar communication integrated baseband signal in the step A1 is as follows:
wherein N is p In order to provide the number of pulses, p=0, 1,.. p -1；N s For the number of symbols, m=0, 1, …，N s -1；N c N=0, 1, …, N as the number of subcarriers c -1; c (n, m, p) is communication modulation information of the p-th pulse, the m-th symbol and the n-th subcarrier, Δf is a subcarrier frequency interval, and t=1/Δf is a time width of the OFDM symbol; t (T) cp Is the time width of the cyclic prefix, T s ＝T cp +T is the time bandwidth of the complete OFDM symbol; t (T) p Is a pulse repetition period; rect (t) is a window function, only when t.epsilon.0, 1]When the value is 1, otherwise, the value is 0;
in the step A1, aiming at c (n, m, p), different ZC sequences are adopted as modulation information of subcarriers in different symbols;
the step A1 specifies N s ＝N p And, the number of ZC sequences is defined as N zc The number of sequences and the number of pulses need to satisfy N zc ＞N p The method comprises the steps of carrying out a first treatment on the surface of the Specifying the length N of ZC sequence k ＝N c -1, varying the parameter μ generates N zc ZC sequences, the length of which is extended to N by zero padding c And is used as modulation information of different subcarriers in one symbol; for N zc Numbering the ZC sequences to obtain ZAnd zc=0, 1,.. zc -1；
Step frequency d of each pulse p Is 0 to N p Random number between-1, number and step frequency d of the p-th pulse p Equal ZC sequence as N of the mth symbol in the first pulse c Modulation information of subcarriers, and p=m=zc, up to which the step frequency of each pulse is modulated in each symbol of the first pulse;
the step A2 specifically comprises the following steps: specifying the number of users in the system as N u The number of users and the number of symbols need to satisfy N u ≤N s Stipulating N u ＝N s For N u Numbering the users to obtainAnd u=0, 1,. -%, N u -1, taking the ZC sequence with the same number as the number of the user to be communicated as N of the mth symbol in the second pulse c Modulation information of the sub-carrier, and u=m=zc, so far, user information to be communicated is modulated in a corresponding symbol of the second pulse;
in the step A4, the baseband signal is up-converted to obtain an integrated transmitting signal, and the expression is:
wherein f p Is the carrier frequency of the p-th pulse, and f p ＝f c +d p B，f c As the base carrier frequency, b=n c Δf is the signal bandwidth;
the step B1 specifically comprises the following steps: since the carrier frequency of the first pulse is known to be f c +d 0 B and d 0 =0, down-converting the first pulse at the communication receiving end to obtain a baseband receiving signal, demodulating the baseband receiving signal to obtain ZC sequences in each symbol, and obtaining the number of the ZC sequences in each symbol by looking up a table, namely, the step frequency of each pulse;
the step B2 specifically comprises the following steps:
step B1 obtains the step frequency d of the second pulse 1 With carrier frequency f c +d 1 B, performing down-conversion on the second pulse at the communication receiving end to obtain a baseband receiving signal, and demodulating the baseband receiving signal to obtain a ZC sequence in each symbol; numbered U u Is numbered ZC zc Performing correlation operation on the demodulation sequence in the mth symbol, wherein u=zc=m, and judging whether the user is a communicated user according to an operation result;
the method for judging the communicated user in the step B2 is as follows:
judging 2N of the obtained normalized correlation sequence k -1 amplitude, if only one amplitude is greater than a set threshold, indicating that the resulting sequence is an autocorrelation sequence, mth symbolThe carried sequence and the ZC sequence with the same number as the user are the same sequence, the user is a communicated user, and the integrated signal needs to be continuously received; if two or more amplitude values are larger than the set threshold value, the obtained sequence is a cross-correlation sequence, the sequence carried by the mth symbol is a replacement sequence, the user is not a communication user, and the integrated signal does not need to be continuously received.
2. The method for generating and receiving radar communication integrated signals based on random step-frequency OFDM according to claim 1, wherein the step A3 specifically includes:
get order 2 l ＜N zc Maximum value of l established, dividing binary communication information into each l and converting into 2 l A binary number for modulating ZC sequences with the same numbers as the conversion values in the third to last N p N of 2 pulses s (N p -2) symbols.
CN202111220945.0A 2021-10-20 2021-10-20 Radar communication integrated signal generation and receiving method based on random step frequency OFDM Active CN113965441B (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN202111220945.0A CN113965441B (en) 2021-10-20 2021-10-20 Radar communication integrated signal generation and receiving method based on random step frequency OFDM
PCT/CN2021/126142 WO2023065374A1 (en) 2021-10-20 2021-10-25 Radar-communication integration signal generating and receiving method based on random step frequency ofdm
KR1020227040030A KR20230058008A (en) 2021-10-20 2021-10-25 Radar communication integrated signal generation and reception method based on random step frequency OFDM

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111220945.0A CN113965441B (en) 2021-10-20 2021-10-20 Radar communication integrated signal generation and receiving method based on random step frequency OFDM

Publications (2)

Publication Number Publication Date
CN113965441A CN113965441A (en) 2022-01-21
CN113965441B true CN113965441B (en) 2023-10-27

Family

ID=79465690

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111220945.0A Active CN113965441B (en) 2021-10-20 2021-10-20 Radar communication integrated signal generation and receiving method based on random step frequency OFDM

Country Status (3)

Country Link
KR (1) KR20230058008A (en)
CN (1) CN113965441B (en)
WO (1) WO2023065374A1 (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104066147A (en) * 2013-03-19 2014-09-24 中兴通讯股份有限公司 Network node searching method, device and equipment based on downlink detection reference signal
CN104982055A (en) * 2013-02-07 2015-10-14 交互数字专利控股公司 Interference measurements and management in directional mesh networks
CN105306399A (en) * 2015-07-24 2016-02-03 西安电子科技大学 Optimization method for radar communication integrated signal
CN108365910A (en) * 2017-01-26 2018-08-03 华为技术有限公司 A kind of launching technique of signal, method of reseptance and equipment
CN110290087A (en) * 2019-07-05 2019-09-27 电子科技大学 A kind of modulation, demodulation method and the device of GFDM signal
CN111953378A (en) * 2020-08-05 2020-11-17 江苏科技大学 Radar communication integrated signal transmission technology based on multi-symbol OFDM

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10502824B2 (en) * 2015-11-09 2019-12-10 Infineon Technologies Ag Frequency modulation scheme for FMCW radar
CN107786480B (en) * 2017-09-28 2019-10-29 清华大学 Radar-communication integration signal creating method and device
CN108627818B (en) * 2018-03-19 2023-11-17 桂林电子科技大学 OFDM-based frequency control array radar communication integrated waveform design method
CN108768446B (en) * 2018-05-30 2019-08-13 西安电子科技大学 The signal waveform design method of low probability of intercept radar communication integrated system

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104982055A (en) * 2013-02-07 2015-10-14 交互数字专利控股公司 Interference measurements and management in directional mesh networks
CN104066147A (en) * 2013-03-19 2014-09-24 中兴通讯股份有限公司 Network node searching method, device and equipment based on downlink detection reference signal
CN105306399A (en) * 2015-07-24 2016-02-03 西安电子科技大学 Optimization method for radar communication integrated signal
CN108365910A (en) * 2017-01-26 2018-08-03 华为技术有限公司 A kind of launching technique of signal, method of reseptance and equipment
CN110290087A (en) * 2019-07-05 2019-09-27 电子科技大学 A kind of modulation, demodulation method and the device of GFDM signal
CN111953378A (en) * 2020-08-05 2020-11-17 江苏科技大学 Radar communication integrated signal transmission technology based on multi-symbol OFDM

Also Published As

Publication number Publication date
WO2023065374A1 (en) 2023-04-27
KR20230058008A (en) 2023-05-02
CN113965441A (en) 2022-01-21

Similar Documents

Publication Publication Date Title
CN101356755B (en) Method and apparatus for pilot signal transmission
CN107800662B (en) Method for reducing peak-to-average power ratio of spread spectrum OFDM signal
CN113726713B (en) Time domain multiplexing frequency shift chirp keying modulation and orthogonal modulation extension method thereof
Bai et al. Double-sub-stream M-ary differential chaos shift keying wireless communication system using chaotic shape-forming filter
CN1939019A (en) Methods and apparatus for generating and processing wideband signals having reduced discrete power spectral density components
CN113315541B (en) Pseudo-random phase sequence spread spectrum modulation method
CN101534278B (en) Time-frequency expansion Orthogonal Frequency Division Multiplexing transmitting and receiving device, method and system
CN101771644B (en) Joint detection and soft decision decoding-based signal receiving method
Huang et al. Constant envelope OFDM RadCom fusion system
CN110808933A (en) Index modulation underwater acoustic multi-carrier communication method based on wavelet packet transformation
Jhingan et al. Performance Evaluation for Wavelet based OFDM system effected by CFO over Rayleigh channel
CN113965441B (en) Radar communication integrated signal generation and receiving method based on random step frequency OFDM
CN1593046A (en) Partial response signaling for orthogonal frequency division multiplexing
CN106685474A (en) Circulating spread spectrum modulation method based on ZC sequence
Khare et al. Effect of Doppler frequency and ber in FFT based OFDM system with Rayleigh fading channel
Mietzner DFT-spread OFDM MIMO-radar–an alternative for reduced crest factors
Liu et al. Carrier interferometry code index modulation aided OFDM-based DCSK communications
CN110581819B (en) Method, device, electronic equipment and storage medium for reducing PAPR
Liu et al. A power-efficient radar waveform compatible with communication
Gupta et al. 5th Generation of Gfdm and analysis of Ser using filter
CN114629763B (en) OFDM system IQ signal demodulation method and device based on neural network
Huang et al. Multicarrier chirp-division multiplexing for wireless communications
Ghanim et al. Analysis of MC-CDMA System in Mobile Communications
Tang et al. Study on the identification method of wavelet packet modulation signals
Hussien et al. Chaotic-based Orthogonal Frequency Division Multiplexing with Index Modulation

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