Imitation radio frequency division multiplexing-oriented non-fuzzy interference-free sensing parameter estimation method and system

Abstract

The invention discloses a non-fuzzy interference-free sensing parameter estimation method for imitated radio frequency division multiplexing. The method comprises the following steps: obtaining the maximum sensing distance of a target to be sensed and the maximum sensing Doppler of the target to be sensed; and determining the frequency of chirp subcarrier spectrum winding according to the maximum sensing distance of the target to be sensed and the maximum sensing Doppler of the target to be sensed. The method has the advantage of being high in communication and perception integration capacity.

Description

Technical Field

[0001] This application relates to the field of communication technology, and more specifically, to a method and system for estimating unambiguous and interference-free sensing parameters for simulated radio frequency multiplexing. Background Technology

[0002] 6G and communication networks using stronger communication standards need to provide high-quality sensing services to achieve the goal of integrated communication and sensing. Therefore, the physical layer communication waveforms in the communication network must possess good sensing performance while simultaneously requiring the design of low-complexity sensing algorithms. Affine Frequency Division Multiplexing (AFDM) is a highly promising communication waveform for future 6G and communication networks using stronger communication standards, offering superior communication performance compared to existing Orthogonal Frequency Division Multiplexing (OFDM).

[0003] The sensing capability of simulated radio frequency division multiplexing (AFDM) technology is relatively weak, as is its integrated communication and sensing capability. Existing methods for improving the sensing capability of AFDM often reduce the communication performance of the technology, making it difficult to achieve a balance between communication performance and sensing capability.

[0004] Prior art discloses a parameter determination method, apparatus, communication device, and readable storage medium, belonging to the field of communication technology. The parameter determination method in this application includes: the communication device acquiring an analog radio frequency division multiplexing (AFDM) parameter set; and determining target AFDM parameters based on the AFDM parameter set. This method adjusts communication and sensing parameters according to the way parameters are determined based on the AFDM parameter set, but it does not integrate communication and sensing. Summary of the Invention

[0005] This invention addresses the weakness of existing technologies in integrating communication and sensing capabilities by providing a non-ambiguous and interference-free sensing parameter estimation method and system for simulated radio frequency multiplexing. This method features strong integrated communication and sensing capabilities.

[0006] The primary objective of this invention is to solve the aforementioned technical problems. The technical solution of this invention is as follows: Unambiguous and interference-free sensing parameter estimation methods for pseudo-RF multiplexing include: S1: Obtain the maximum sensing distance and the maximum sensing Doppler of the target to be sensed; S2: Determine the number of times the chirped subcarrier spectrum is wrapped based on the maximum sensing distance of the target to be sensed and the maximum sensing Doppler of the target to be sensed.

[0007] Furthermore, in step S2, the formula for calculating the number of times the chirped subcarrier spectrum is wrapped is as follows:

[0008]

[0009] Represents the Doppler dimensional distance. This represents the duration of the spectrum of a single chirped subcarrier. Indicates the Nyquist sampling interval. This indicates the number of times the chirped subcarrier spectrum is wrapped. This indicates rounding up 'a'.

[0010] Furthermore, in step S2, the formula for calculating the number of times the chirped subcarrier spectrum is wrapped is as follows:

[0011]

[0012] Represents the Doppler dimensional distance. This represents the duration of the spectrum of a single chirped subcarrier. Indicates the Nyquist sampling interval. This indicates the number of times the chirped subcarrier spectrum is wrapped. This indicates a pilot protection symbol, where N represents the total number of subcarriers. This indicates rounding up 'a'.

[0013] A sensing method, comprising: S01: The transmitter generates a sensing integrated signal based on the number of times the chirped subcarrier spectrum is wrapped. S02: The transmitting end sends the integrated sensing signal to the first receiving end and the second receiving end respectively through the channel; S03: The first receiving end parses the received integrated sensing signal to obtain a communication signal; the second receiving end parses the integrated sensing signal to obtain the sensing information of the target to be detected.

[0014] Further, in step S03, the second receiving end parses the integrated sensing signal to obtain the sensing information of the target to be detected, including: S0301: Perform matched filtering on the integrated sensing signal to obtain a matched-filtered integrated sensing signal; S0302: Perform multi-target detection on the matched-filtered integrated sensing signal to obtain the sensing information of the target to be detected; The matched filter formula is as follows:

[0015] This represents the m-th subcarrier in the integrated sensing signal. This represents the integrated sensor signal after conjugation operation. Indicates time delay. Let j denote Doppler, j denote the complex field, and t denote time. This represents the sensing pulse of the target to be detected.

[0016] Furthermore, the integrated sensing signal includes pilot signals, pilot protection symbols, and data symbols.

[0017] Furthermore, the formula for the data symbols of the integrated sensing signal is as follows:

[0018] This represents the m-th subcarrier in the integrated sensing signal, where m represents the subcarrier index. The slope representing the digital chirped signal. The auxiliary phase representing the chirped signal. Indicates the Nyquist sampling interval. denoted by , j represents the complex domain, t represents time, and q represents the sequence number of the chirped subcarrier spectrum winding.

[0019] Furthermore, the relationship between the number of times the chirped subcarrier spectrum is wrapped and the slope of the digital chirped signal is as follows:

[0020] The slope of the digital chirped signal is represented by N, which represents the total number of subcarriers.

[0021] An unambiguous and interference-free sensing parameter estimation system for simulated radio frequency multiplexing includes: Perception parameter acquisition module: acquires the maximum sensing distance and the maximum sensing Doppler of the target to be sensed; Spectrum winding determination module: Determines the number of times the chirped subcarrier spectrum is wound based on the maximum sensing distance of the target to be sensed and the maximum sensing Doppler of the target to be sensed.

[0022] A sensing system, comprising: Signal generation module: Based on the number of times the chirped subcarrier spectrum is wrapped, the transmitter generates an integrated sensing signal; Signal transmission module: The transmitter sends the integrated sensing signal to the first receiver and the second receiver respectively through the channel; Signal perception and analysis module: The first receiving end analyzes the received integrated perception signal to obtain the communication signal; the second receiving end analyzes the integrated perception signal to obtain the perception information of the target to be detected.

[0023] Compared with the prior art, the beneficial effects of the present invention are: This invention obtains the maximum sensing distance and maximum sensing Doppler of the target; and determines the number of chirped subcarrier spectrum wrapping operations based on the maximum sensing distance and maximum sensing Doppler of the target. This invention ensures that, after matching filtering based on the determined number of chirped subcarrier spectrum wrapping operations, the pulses of multiple targets are all within a certain range, thereby achieving unambiguous sensing.

[0024] Meanwhile, based on the number of times the chirped subcarrier spectrum is wrapped, the transmitter generates an integrated sensing signal; the transmitter sends the integrated sensing signal to the first receiver and the second receiver respectively through the channel; the first receiver parses the received integrated sensing signal to obtain a communication signal; the second receiver parses the integrated sensing signal to obtain the sensing information of the target to be detected; this algorithm is flexible and simple in complexity, and can significantly improve the sensing capability of the simulated radio frequency division multiplexing (AFDM) system without reducing its original excellent communication performance, thus making the integrated communication and sensing capability strong. Attached Figure Description

[0025] Figure 1 The flowchart is for the unambiguous and interference-free sensing parameter estimation method for simulated radio frequency multiplexing provided in Example 1.

[0026] Figure 2 A flowchart of a sensing method provided in Example 1.

[0027] Figure 3 This is a schematic diagram of the simulated radio frequency multiplexing communication system provided in Example 1.

[0028] Figure 4 The time-frequency distribution diagram of the chirped subcarrier in the simulated radio frequency multiplexing provided in Example 1.

[0029] Figure 5 This is a schematic diagram of a single / dual base station simulated radio frequency multiplexing communication and sensing integrated system provided in Example 1.

[0030] Figure 6 This is a schematic diagram of a single-base station simulated radio frequency multiplexing communication and sensing integrated system provided in Example 1.

[0031] Figure 7 This is a schematic diagram of the dual-base station simulated radio frequency multiplexing communication and sensing integrated system provided in Example 1.

[0032] Figure 8 This is a schematic diagram of the dual-base station simulated radio frequency multiplexing communication and sensing integrated system provided in Example 1.

[0033] Figure 9This is a schematic diagram of the ambiguity function of the simulated radio frequency multiplexing pilot signal at a 45-degree angle provided in Example 1.

[0034] Figure 10 This is a top-down view of the ambiguity function of the simulated radio frequency multiplexing pilot signal provided in Example 1.

[0035] Figure 11 This is a schematic diagram of the ambiguity function rotation periodic pulse of the simulated radio frequency multiplexing pilot signal provided in Example 1.

[0036] Figure 12 The diagram shows the unambiguous quadrilateral of the ambiguity function of the pilot signal provided in Example 1.

[0037] Figure 13 This is a schematic diagram of the simulated radio frequency multiplexing symbol design provided in Example 1.

[0038] Figure 14 This is a schematic diagram of the ambiguity function of the transmitted signal and its pilot component provided in Example 1 at a 45-degree angle.

[0039] Figure 15 This is a top-view schematic diagram of the ambiguity function of the transmitted signal and its pilot component provided in Example 1.

[0040] Figure 16 The simulation parameter diagram provided for Example 1.

[0041] Figure 17 The output diagram of the sensing matched filter signal when the parameters provided in Example 1 are relatively small.

[0042] Figure 18 The output diagram of the sensing matched filter signal when the parameters provided in Example 1 are relatively large. Detailed Implementation

[0043] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this patent. To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions; It will be understood by those skilled in the art that certain well-known structures and their descriptions may be omitted in the accompanying drawings.

[0044] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0045] Example 1 like Figure 1 As shown, a non-ambiguous and interference-free sensing parameter estimation method for pseudo-RF multiplexing includes: S1: Obtain the maximum sensing distance and the maximum sensing Doppler of the target to be sensed; S2: Determine the number of times the chirped subcarrier spectrum is wrapped based on the maximum sensing distance of the target to be sensed and the maximum sensing Doppler of the target to be sensed.

[0046] Furthermore, in step S2, the formula for calculating the number of times the chirped subcarrier spectrum is wrapped is as follows:

[0047]

[0048] Represents the Doppler dimensional distance. This represents the duration of the spectrum of a single chirped subcarrier. Indicates the Nyquist sampling interval. This indicates the number of times the chirped subcarrier spectrum is wrapped. This indicates rounding up 'a'.

[0049] Furthermore, in step S2, the formula for calculating the number of times the chirped subcarrier spectrum is wrapped is as follows:

[0050]

[0051] Represents the Doppler dimensional distance. This represents the duration of the spectrum of a single chirped subcarrier. Indicates the Nyquist sampling interval. This indicates the number of times the chirped subcarrier spectrum is wrapped. This indicates a pilot protection symbol, where N represents the total number of subcarriers. This indicates rounding up 'a'.

[0052] like Figure 2 As shown, a sensing method includes: S01: The transmitter generates a sensing integrated signal based on the number of times the chirped subcarrier spectrum is wrapped. S02: The transmitting end sends the integrated sensing signal to the first receiving end and the second receiving end respectively through the channel; S03: The first receiving end parses the received integrated sensing signal to obtain a communication signal; the second receiving end parses the integrated sensing signal to obtain the sensing information of the target to be detected.

[0053] It should be noted that the sensing method provided by this invention greatly improves the reliability and practicality of traditional simulated radio frequency multiplexing (RFD) systems. It is applicable to all integrated RFD communication and sensing systems, exhibiting high robustness, extremely low complexity, and high flexibility.

[0054] like Figure 3 As shown, assuming is The transmitter first assigns a vector of quadrature amplitude modulation (QAM) information symbols to be transmitted. Each information symbol is modulated to On each chirped subcarrier, its mathematical expression is as follows: (Formula 1) in, Indicates the transmission of time-domain signals, variables Represents a continuous-time variable, variable Represents subcarrier index, It is The time delay of each subcarrier is specifically expressed as follows: (Formula 2) in (Formula 3) It is the subcarrier segmentation time point. It is the Nyquist sampling interval. It is the total duration of the transmitted signal. . and These are two fundamental parameters of AFDM. It is the slope of the digital chirped signal, and its value satisfies It is a positive integer (the physical meaning of parameter C is) Figure 4 (Number of times the AFDM chirped subcarrier spectrum is wrapped) parameters It is the auxiliary phase of the chirped signal, and its value is not restricted.

[0055] like Figure 4 As shown, the vertical axis variable For frequency, , As can be seen, the bandwidth occupied by the subcarriers in the simulated radio frequency multiplexing is... Its instantaneous frequency increases linearly with time, and when its instantaneous frequency reaches... The time jumps to 0 at the next moment, and then continues to increase linearly with time, repeating this cycle until the total signal duration is reached. Before sending to the channel, it is necessary to transmit time-domain signals. Add a duration in front The cyclic prefix, where is Maximum normalized delay spread of the channel.

[0056] Modeling the dual-dispersion wireless channel in the time-delay-Doppler domain yields: (Formula 4) Formula 4 indicates that the dual-dispersion wireless channel consists of P paths. , Let represent the fading coefficient, time delay, and Doppler of the i-th (i=1,…,P) path segment, respectively. and It is the digital domain normalized time delay and normalized Doppler frequency shift. and Represents the integer part. and Represents the fractional part.

[0057] The transmitted time-domain signal reaches the receiver after passing through the dual-dispersion wireless channel described above. The receiver then removes the cyclic prefix from the received time-domain signal to obtain the received time-domain signal. Its relationship with the channel and the transmitted time-domain signal The relationship is (Formula 5) in It receives time-domain Gaussian white noise. Operators represent Modulus. The physical meaning of Formula 5 is that the received signal is the linear superposition of P signal replicas obtained after the transmitted signal has passed through P paths with different time delays and Doppler frequency offsets.

[0058] For received time domain signals After performing matched filtering, we get (Formula 6) Then, by performing channel estimation and signal detection in traditional communication, the data sent by the transmitter can be recovered.

[0059] like Figure 5 As shown, based on the traditional simulated radio frequency multiplexing (RFD) communication system, this patent further proposes a single / dual base station communication sensing system based on simulated RFD, designing a single-base station unambiguous sensing algorithm and a dual-base station interference-free sensing algorithm. The blue base station in the lower left corner is an AFDM-ISAC transmitter and also a single-base station sensing receiver; the yellow car on the right is a communication receiver and can also be a dual-base station sensing receiver; the lower right corner is an independent dual-base station sensing receiver; and the two drones represent the two targets to be sensed.

[0060] like Figure 6As shown, in addition to the traditional communication transmission link, single-base station AFDM-ISAC also has a single-base station sensing link. Specifically, the single-base station sensing link and the communication transmission link share the transmission signal, but they pass through a communication dual-selection channel and a single-base station sensing dual-selection channel respectively. The scatterers in these two channels are different, so the two channels are not entirely the same.

[0061] Let the signal that returns to the monostatic sensing receiver after passing through the sensing channel be denoted as . Its mathematical expression can be obtained similarly through Formula 5. The monostatic sensing receiver first performs matched filtering with the known signal, where the mathematical expression of generalized matched filtering is as follows: (Formula 7) Matched filtering for monostatic sensing. And known signal That is, to send a signal This is because the monostatic sensing receiver and the integrated sensing signal transmitter are located in the same position, and their information is fully shared. Then, target detection is performed based on the location of high energy in the obtained matched filter.

[0062] like Figure 7 As shown, specifically, the sensing link and communication transmission link of the integrated sensing and receiving dual-base station share the same transmission signal and pass through the same dual-selection channel, that is, communication and sensing share the dual-selection channel. Let the signal passing through the shared dual-selection channel to the integrated sensing receiver be denoted as... Its mathematical expression can also be obtained through Formula 5. Then, the integrated sensing receiver first transmits the received signal to the communication processing module and the sensing processing module respectively for communication and sensing processing. Similarly, the sensing processing module first... Matched filtering is performed with the known signal. At this point, since the sensing receiver and the integrated inductive signal transmitter are located in different positions, the known signal is only the pilot portion of the transmitted signal; its random data portion is unknown. Finally, target detection is performed based on the location of high energy in the obtained matched filter.

[0063] like Figure 8 As shown, based on the traditional communication transmission link, the inductive receiving independent dual-base station AFDM-ISAC also has a dual-base station sensing link. Specifically, the inductive receiving independent dual-base station sensing link and the communication transmission link share the transmission signal, but they pass through a communication dual-selection channel and a dual-base station sensing dual-selection channel respectively. The scatterers in these two channels are different, so the two channels are not entirely identical. Further, let the signal arriving at the dual-base sensing receiver be denoted as... Its mathematical expression can also be obtained through Equation 5. The bistatic sensing receiver first processes... Matched filtering is performed on the known signal. Similar to the dual-base station AFDM-ISAC system with integrated sensing and receiving, since the sensing receiver and the integrated sensing signal transmitter are located in different positions, the known signal can only be the pilot portion of the transmitted signal; its random data portion is unknown. Finally, target detection is performed based on the location of high energy in the obtained matched filter.

[0064] The above analysis covers three generalized analog radio frequency division multiplexing (AFDM-ISAC) systems: a single base station, a dual base station with integrated sensing and receiving, and a dual base station with independent sensing and receiving. These systems can essentially cover or be combined into all ISAC scenarios. Specifically, all three ISAC systems require matched filtering of the received sensing signal and the known signal. The usable known signal differs depending on whether the sensing receiver and transmitter are located at the same position. However, regardless of whether it's a single base station or either of the two dual base station types, the known signal includes the pilot portion of the transmitted signal. Since the output of the matched filter is a linear superposition of copies obtained by applying the ambiguity function of the known signal to the corresponding target's time delay and Doppler shift, the following analysis examines the ambiguity function of the pilot portion of the transmitted signal. Based on the conclusions, an AFDM-ISAC system design is proposed, along with corresponding parameter selection strategies to improve the sensing performance of the AFDM-ISAC system.

[0065] Further, in step S03, the second receiving end parses the integrated sensing signal to obtain the sensing information of the target to be detected, including: S0301: Perform matched filtering on the integrated sensing signal to obtain a matched-filtered integrated sensing signal; S0302: Perform multi-target detection on the matched-filtered integrated sensing signal to obtain the sensing information of the target to be detected; The matched filter formula is as follows: (Formula 8) This represents the m-th subcarrier in the integrated sensing signal. This represents the integrated sensor signal after conjugation operation. Indicates time delay. Let j denote Doppler, j denote the complex field, and t denote time. This represents the sensing pulse of the target to be detected.

[0066] It should be noted that in the above formula, the simulated radio frequency division multiplexing (AFDM) pilot symbol is preset to unit 1 and placed on the m-th subcarrier. Its physical meaning is that the m-th subcarrier is time-delayed from itself. and Doppler Integrating the conjugates after the conjugates, and substituting Equation 2 into the above equation, we get:

[0067]

[0068] (Formula 9) Visualizing the above formula, we can obtain... Figure 9 , Figure 10 .like Figure 9 As shown, the ambiguity function of the simulated radio frequency division multiplexing (AFDM) pilot signal exhibits a periodic pulse distribution along both the rotating time delay and the rotating Doppler dimension. This is determined by the chirp characteristics of the AFDM subcarriers, as explained in the following principle. Figure 11 As shown. Specifically, the solid line represents the time-frequency distribution of the original pilot signal, and the dashed line represents the pilot signal after time delay. and Doppler The subsequent time-frequency distribution diagram shows that at that time... and Doppler When the slope of the time-frequency distribution diagram of the original pilot signal is satisfied, the two signals can achieve a high degree of overlap, corresponding to the excitation of a high-energy pulse on the ambiguity function. This pattern causes the ambiguity function to be distributed along the rotating Doppler dimension. Furthermore, due to the time delay... When large enough Figure 11 As shown on the right, the two signals can also achieve a high degree of overlap, and can similarly excite a high-energy pulse. This pattern determines that the ambiguity function of the AFDM pilot signal has multiple parallel lines parallel to the rotating Doppler, formed by the periodic pilot, such as... Figure 10 As shown.

[0069] Based on this, the ambiguity function of the AFDM pilot signal is formed as follows: Figure 12 The virtual grid outlined by the dashed lines shows that every four adjacent pulses can form a parallelogram. Specifically, the time delay distance between two adjacent pulses distributed along the rotational Doppler dimension is... Doppler dimensional distance is ,in The AFDM subcarrier spacing is equal to the reciprocal of the total AFDM duration. This means that the AFDM parameter C determines the distribution characteristics of the periodic pulses of the ambiguity function of the AFDM pilot signal. Specifically, the delineated virtual grid equivalently assigns each pulse a parallelogram of the same shape and size as the parallelogram that can be formed by every four adjacent pulses, such as... Figure 12 The parallelogram assigned to the pulse located at the origin is shown. Let... Then the x-coordinate of point c is The vertical axis is ( - ) The x-coordinate of point c' is = The vertical axis is The x-coordinate of point a' is = The vertical axis is - The x-coordinate of point g' is = The vertical axis is The x-coordinate of point i' is = The vertical axis is This indicates that the AFDM parameter C determines the shape of the parallelogram. Furthermore, since the output of the matched filter at the sensing receiver is a linear superposition of copies obtained by applying time delay and Doppler shift to the ambiguity function of the known signal, the pulse period distribution characteristics of the ambiguity function of the AFDM pilot signal may lead to ambiguity decision, i.e., it is impossible to determine which target's ambiguity function component a certain pulse belongs to, thus causing ambiguity sensing.

[0070] After matched filtering, the pulses of multiple targets will all fall within the corresponding parallelogram range, thus achieving unambiguous perception. Therefore, this parallelogram is named the unambiguous parallelogram.

[0071] Furthermore, the integrated sensing signal includes pilot signals, pilot protection symbols, and data symbols.

[0072] It should be noted that single-base station sensing and communication share pilots, and a single pilot symbol can achieve the sensing resolution limit in both distance and velocity dimensions. The process of dynamically adjusting spectrum winding is simple and flexible, greatly improving the spectrum utilization and sensing accuracy of the single-base station integrated sensing system. Dual-base station sensing and communication share pilots and protection symbols, which improves the spectrum utilization of the integrated sensing system while avoiding interference from random data symbols to the determined pilot symbols, thus improving the sensing accuracy of the dual-base station integrated sensing system.

[0073] like Figure 13 As shown, for integrated sensing with dual base stations, the transmitted signal includes not only deterministic pilot signals but also random data. Matching the received signal with the pilot signal causes data interference with the pilot, resulting in interference with the dual-base station sensing. To mitigate this interference, Q pilot symbols can be inserted between the pilot and the data.

[0074] At this point, the ambiguity function between the transmitted signal and its pilot components is as follows: Figure 14 , Figure 15 As shown, the pilot component and data component of the ambiguity function of the transmitted signal and its pilot component are clearly separated, and a parallelogram smaller than the unambiguous quadrilateral can be further delineated. The x-coordinate of point p is... = The vertical axis is The x-coordinate of point q is = The vertical axis is The x-coordinate of point u is = The vertical axis is The x-coordinate of point z is = The vertical axis is

[0075] When the target of the channel can be encompassed as... Figure 15 Within the parallelogram shown, pilot signals and data will not interfere with each other, thus achieving interference-free sensing between dual base stations. Therefore, this smaller parallelogram is named the interference-free parallelogram. In particular, the number of guard symbols should be set according to the maximum delay spread and maximum Doppler spread of the channel. The larger the maximum delay spread and maximum Doppler spread of the channel, the larger the number of guard symbols should be to meet the interference-free condition.

[0076] Furthermore, the formula for the data symbols of the integrated sensing signal is as follows:

[0077] This represents the m-th subcarrier in the integrated sensing signal, where m represents the subcarrier index. The slope representing the digital chirped signal. The auxiliary phase representing the chirp signal. Indicates the Nyquist sampling interval. denoted by , j represents the complex domain, t represents time, and q represents the sequence number of the chirped subcarrier spectrum winding.

[0078] Furthermore, the relationship between the number of times the chirped subcarrier spectrum is wrapped and the slope of the digital chirped signal is as follows:

[0079] The slope of the digital chirped signal is represented by N, which represents the total number of subcarriers.

[0080] An unambiguous and interference-free sensing parameter estimation system for simulated radio frequency multiplexing includes: Perception parameter acquisition module: acquires the maximum sensing distance and the maximum sensing Doppler of the target to be sensed; Spectrum winding determination module: Determines the number of times the chirped subcarrier spectrum is wound based on the maximum sensing distance and the maximum sensing Doppler of the target.

[0081] A sensing system, comprising: Signal generation module: Based on the number of times the chirped subcarrier spectrum is wrapped, the transmitter generates an integrated sensing signal; Signal transmission module: The transmitter sends the integrated sensing signal to the first receiver and the second receiver respectively through the channel; Signal perception and analysis module: The first receiving end analyzes the received integrated perception signal to obtain the communication signal; the second receiving end analyzes the integrated perception signal to obtain the perception information of the target to be detected.

[0082] This invention is verified through numerical simulation. Assume the sensing channel has four paths, with (time delay, Doppler) values ​​of (0,0), (3,4), and (4,0). 5.1 (9.7) 2.3 ) and (11.8 -3.5 The remaining parameters are as follows: Figure 16 As shown.

[0083] like Figure 17 As shown, when the AFDM (Analog Radio Division Multiplexing) parameter C=1, it is possible to roughly determine that there are four targets, but it is impossible to determine the time delay and Doppler of each target. This is because C is set too small at this time, and its Doppler sensing range is much smaller than the maximum Doppler of the target in the channel. That is, the target cannot be included within the unambiguous parallelogram assigned to the origin, so the parameter is ambiguous. However, when C is set large enough (C=13), as... Figure 18 As shown, it can satisfy the condition that all targets can be included within the parallelogram assigned to the origin, thus achieving unambiguous perception.

[0084] The same or similar labels correspond to the same or similar parts; The terms used to describe positional relationships in the accompanying drawings are for illustrative purposes only and should not be construed as limiting this patent. Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for estimating unambiguous and interference-free sensing parameters for simulated radio frequency multiplexing, characterized in that: include: S1: Obtain the maximum sensing distance and the maximum sensing Doppler of the target to be sensed; S2: Determine the number of times the chirped subcarrier spectrum is wrapped based on the maximum sensing distance of the target to be sensed and the maximum sensing Doppler of the target to be sensed.

2. The unambiguous and interference-free sensing parameter estimation method for pseudo-RF multiplexing according to claim 1, characterized in that, In step S2, the formula for calculating the number of times the chirped subcarrier spectrum is wrapped is as follows: Represents the Doppler dimensional distance. This represents the duration of the spectrum of a single chirped subcarrier. Indicates the Nyquist sampling interval. This indicates the number of times the chirped subcarrier spectrum is wrapped. This indicates rounding up 'a'.

3. The unambiguous and interference-free sensing parameter estimation method for pseudo-RF multiplexing according to claim 1, characterized in that, In step S2, the formula for calculating the number of times the chirped subcarrier spectrum is wrapped is as follows: Represents the Doppler dimensional distance. This represents the duration of the spectrum of a single chirped subcarrier. Indicates the Nyquist sampling interval. This indicates the number of times the chirped subcarrier spectrum is wrapped. This indicates a pilot protection symbol, where N represents the total number of subcarriers. This indicates rounding up 'a'.

4. A sensing method, applied to the parameter estimation method according to any one of claims 1 to 3, characterized in that, include: S01: The transmitter generates a sensing integrated signal based on the number of times the chirped subcarrier spectrum is wrapped. S02: The transmitting end sends the integrated sensing signal to the first receiving end and the second receiving end respectively through the channel; S03: The first receiving end parses the received integrated sensing signal to obtain a communication signal; the second receiving end parses the integrated sensing signal to obtain the sensing information of the target to be detected.

5. The sensing method according to claim 4, characterized in that, In step S03, the second receiving end parses the integrated sensing signal to obtain the sensing information of the target to be detected, including: S0301: Perform matched filtering on the integrated sensing signal to obtain a matched-filtered integrated sensing signal; S0302: Perform multi-target detection on the matched-filtered integrated sensing signal to obtain the sensing information of the target to be detected; The matched filter formula is as follows: This represents the m-th subcarrier in the integrated sensing signal. This represents the integrated sensor signal after conjugation operation. Indicates time delay. Let j denote Doppler, j denote the complex field, and t denote time. This represents the sensing pulse of the target to be detected.

6. The sensing method according to claim 4, characterized in that, The integrated sensing signal includes pilot signals, pilot protection symbols, and data symbols.

7. The sensing method according to claim 6, characterized in that, The formula for the data symbols of the integrated sensing signal is as follows: This represents the m-th subcarrier in the integrated sensing signal, where m represents the subcarrier index. The slope representing the digital chirped signal. The auxiliary phase representing the chirp signal. Indicates the Nyquist sampling interval. denoted by , j represents the complex domain, t represents time, and q represents the sequence number of the chirped subcarrier spectrum winding.

8. The sensing method according to claim 7, characterized in that, The relationship between the number of times the chirped subcarrier spectrum is wrapped and the slope of the digital chirped signal is as follows: The slope of the digital chirped signal is represented by N, which represents the total number of subcarriers.

9. A non-ambiguous and interference-free sensing parameter estimation system for simulated radio frequency multiplexing, applied to the parameter estimation method described in any one of claims 1 to 3, characterized in that, include: Perception parameter acquisition module: acquires the maximum sensing distance and the maximum sensing Doppler of the target to be sensed; Spectrum winding determination module: Determines the number of times the chirped subcarrier spectrum is wound based on the maximum sensing distance and the maximum sensing Doppler of the target.

10. A sensing system applied to the sensing method according to any one of claims 4 to 8, characterized in that, include: Signal generation module: Based on the number of times the chirped subcarrier spectrum is wrapped, the transmitter generates an integrated sensing signal; Signal transmission module: The transmitter sends the integrated sensing signal to the first receiver and the second receiver respectively through the channel; Signal perception and analysis module: The first receiving end analyzes the received integrated perception signal to obtain the communication signal; the second receiving end analyzes the integrated perception signal to obtain the perception information of the target to be detected.

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