Ultrasonic distance measuring method, ultrasonic distance measuring system, storage medium and program product

Abstract

The application discloses an ultrasonic ranging method, an ultrasonic ranging system, a storage medium and a program product, and relates to the technical field of intelligent sensing. The method comprises the following steps: a sending end generates a plurality of candidate sequence codes in a time domain based on orthogonal symbols, the candidate sequence codes are generated by at least one of the following methods: time domain arrangement, adjustment of symbol intervals, combination, random arrangement and adjustment of symbol intervals, a target sequence code is selected from the candidate sequence codes, and the target sequence code is shared with a receiving end; a target ultrasonic signal containing the target sequence code is broadcast to the receiving end; after receiving the target ultrasonic signal returned by the receiving end, the distance between the sending end and the receiving end is determined; the receiving end receives at least one ultrasonic signal; when a target ultrasonic signal matched with the target sequence code is identified, a transmission channel of the target ultrasonic signal is subjected to collision detection; if there is no collision in the current channel or the collision in the channel is solved, the receiving end and the sending end are subjected to ranging based on the target ultrasonic signal.

Description

Technical Field

[0001] The present application relates to the field of intelligent sensing technology, and in particular to an ultrasonic ranging method, an ultrasonic ranging system, a storage medium, and a program product. Background Art

[0002] Since channel resource allocation information between distributed systems is not interoperable, channel conflicts often occur between multiple distributed systems in the absence of centralized coordination, making ranging between distributed systems difficult to perform efficiently and reliably in practical applications.

[0003] Existing technologies for resolving channel conflicts use carrier sensing, time slot reservation, and multiplexing. The carrier sensing mechanism continuously monitors the channel, transmitting when idle and delaying otherwise. However, since ultrasonic ranging signals are short bursts with long sensing cycles, the carrier sensing mechanism is not adaptable to ultrasonic ranging and conflicts will still occur. The time slot reservation mechanism relies on a dedicated out-of-band negotiation channel for time slot pre-allocation, which is considered centralized coordination and violates the principle of distributed autonomy. Multiplexing technologies include time division multiplexing, frequency division multiplexing, and code division multiplexing. Time division multiplexing requires centralized coordination, which violates the principle of distributed autonomy. Frequency division multiplexing uses a narrow ultrasonic bandwidth, which can only be divided into four sub-channels. There is also frequency shift caused by the Doppler effect, resulting in frequency band overlap. Code division multiplexing uses pseudo-random sequences, but the number of codes is limited, making it unable to meet large-scale requirements. In summary, existing technologies in distributed ultrasonic ranging scenarios still face problems such as channel conflicts, making it difficult to meet the needs of large-scale distributed systems.

[0004] The above content is only used to assist in understanding the technical solution of this application and does not constitute an admission that the above content is prior art. Summary of the Invention

[0005] The main purpose of this application is to provide an ultrasonic ranging method, an ultrasonic ranging system, a storage medium and a program product, aiming to solve the problem of channel conflict faced by the existing technology in distributed ultrasonic ranging scenarios and the technical problem that it is difficult to meet the needs of large-scale distributed systems.

[0006] To achieve the above-mentioned objectives, the present application proposes an ultrasonic ranging method, which is applied to a transmitting end. The method includes: generating multiple candidate sequence codes compressed in the time domain based on orthogonal code elements, wherein the generating multiple candidate sequence codes compressed in the time domain based on orthogonal code elements includes at least one of the following methods: (a) randomly permuting the orthogonal code elements in the time domain to form candidate sequence codes; (b) adjusting the code element spacing between adjacent code elements in the random permutation result of the orthogonal code elements to form candidate sequence codes; (c) combining the random permutation and the code element spacing adjustment between adjacent code elements to form candidate sequence codes;

[0007] Selecting a target sequence code from the plurality of candidate sequence codes, and sharing the target sequence code with a receiving end;

[0008] A target ultrasonic signal containing the target sequence code is broadcasted to a receiving end, the target ultrasonic signal returned by the receiving end is received, and a distance to the receiving end is determined based on the target ultrasonic signal.

[0009] In one embodiment, the orthogonal code elements are signals that are orthogonal to each other in the frequency domain or the code domain, and the orthogonal code elements include a first code element and a second code element.

[0010] To achieve the above objectives, the present application proposes an ultrasonic ranging method, which is applied to a receiving end. The method includes:

[0011] receiving at least one ultrasonic signal, and upon identifying a target ultrasonic signal matching a target sequence code, performing conflict detection on a transmission channel of the target ultrasonic signal under multiple decisions, wherein the target sequence code is selected from candidate sequence codes formed according to at least one of the following methods: (a) randomly permuting orthogonal symbols in the time domain; (b) adjusting the symbol spacing between adjacent symbols in the random permutation result of the orthogonal symbols; and (c) combining random permutation and adjustment of the symbol spacing between adjacent symbols, wherein the target sequence code is pre-shared by a transmitting end and a receiving end, and conflicts include coverage conflicts, congestion conflicts, and channel conflicts.

[0012] If a conflict is detected, a conflict resolution decision is triggered under the corresponding conflict; if no conflict is detected, the distance between the receiving end and the transmitting end is measured based on the target ultrasonic signal.

[0013] In one embodiment, after the step of receiving at least one ultrasonic signal, the method further comprises:

[0014] If the target sequence code is not identified in each ultrasonic signal, it is determined to be a coverage conflict, and the transmitting end is notified to resend the target ultrasonic signal containing the target sequence code;

[0015] The step of performing conflict detection on the transmission channel of the target ultrasonic signal under multiple decisions includes:

[0016] If no coverage conflict occurs and the peak-to-average ratio of the target ultrasonic signal is lower than a preset peak-to-average ratio threshold, it is determined to be a congestion conflict, and the transmitting end is notified to resend the target ultrasonic signal containing the target sequence code;

[0017] If no congestion conflict occurs and the relative relationship between the arrival time difference of the first target ultrasonic signal and the second target ultrasonic signal and the signal strength of the first target ultrasonic signal and the second target ultrasonic signal does not conform to the law of sound wave reflection, it is determined to be a channel conflict, and the transmitting end is notified to reselect the target sequence code and generate a new target ultrasonic signal for broadcast.

[0018] In one embodiment, the orthogonal code element includes a first code element and a second code element, and before the step of performing ranging on a receiving end and a transmitting end of the ultrasonic signal based on the target ultrasonic signal, the step further includes:

[0019] Identify the time domain forward shift feature of the first symbol correlation peak and the time domain backward shift feature of the second symbol correlation peak;

[0020] Calculating a Doppler frequency offset estimate at a relative moving speed between a transmitting end and a receiving end according to the time domain forward shift feature and the time domain backward shift feature;

[0021] Time delay compensation is performed on the target ultrasonic signal according to the Doppler frequency offset estimation to eliminate the Doppler effect of the target ultrasonic signal.

[0022] In one embodiment, the step of measuring the distance between the receiving end and the transmitting end of the ultrasonic signal based on the target ultrasonic signal includes:

[0023] Obtain a first timestamp and a second timestamp of the target ultrasonic signal sent by the transmitting end, wherein the first timestamp is the first time when the transmitting end records that the target ultrasonic signal is sent, and the second timestamp is the second time when the receiving end records that the target ultrasonic signal is received;

[0024] When returning the target ultrasonic signal to the transmitting end, obtaining a third timestamp and a fourth timestamp, wherein the third timestamp is a third time recorded by the receiving end when the receiving end sends the target ultrasonic signal, and the fourth timestamp is a fourth time recorded by the transmitting end when the transmitting end receives the target ultrasonic signal;

[0025] Calculating a propagation delay of a target ultrasonic signal based on a first difference between the fourth timestamp and the first timestamp, and a second difference between the third timestamp and the second timestamp;

[0026] The distance between the receiving end and the transmitting end of the ultrasonic signal is obtained according to the propagation delay and the propagation speed of the ultrasonic wave.

[0027] In one embodiment, the orthogonal code element includes a first code element and a second code element, and after the step of receiving at least one ultrasonic signal, the method further includes:

[0028] Performing filtering on the received ultrasonic signal to obtain a preprocessed ultrasonic signal;

[0029] Calculating a first channel response curve of the preprocessed ultrasonic signal and a first code element and a second channel response curve of the second code element;

[0030] Searching, from the first channel response curve and the second channel response curve based on the symbol interval after time domain compression, for a correlation peak combination that matches the time domain distribution of the target sequence code, while eliminating the mutual correlation interference between the first channel response curve and the second channel response curve;

[0031] According to the time domain position of the correlation peak combination and the consistency of the coding interval, a target ultrasonic signal matching the time domain characteristics of the target sequence coding is determined.

[0032] In addition, to achieve the above objectives, the present application also proposes an ultrasonic ranging system, which includes: a transmitting end and a receiving end, and the transmitting end and / or the receiving end are configured to implement the steps of the ultrasonic ranging method as described above.

[0033] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium. A computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the ultrasonic ranging method described above are implemented.

[0034] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps of the ultrasonic ranging method described above are implemented.

[0035] One or more technical solutions proposed in this application have at least the following technical effects:

[0036] Existing collision avoidance mechanisms (carrier sensing, time slot reservation, and multiplexing) have problems such as insufficient adaptability, reliance on centralized coordination, or limited coding resources in distributed scenarios, resulting in frequent channel conflicts.

[0037] This application uses at least one of the following methods: (a) randomly arranging orthogonal code elements in the time domain; (b) adjusting the code element interval between adjacent code elements in the random arrangement result of orthogonal code elements; (c) combining random arrangement and code element interval adjustment between adjacent code elements to generate a large number of candidate sequence codes. This can improve the code element density per unit time through time domain compression, so that more orthogonal code element combinations can be arranged under the same code length. By adjusting the code element interval, the fixed code element interval limit is broken, the coding space dimension is further increased, the number of candidate sequence codes is greatly increased, and the probability of multi-device coding conflicts is reduced. The coding method mentioned in this application allows devices to autonomously generate candidate sequence codes without relying on global codebook allocation, adapting to distributed scenarios, and solving the technical problem that existing technologies are difficult to meet the needs of large-scale distributed scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings, which are incorporated herein and constitute part of the specification, illustrate embodiments consistent with the application and, together with the description, serve to explain the principles of the application.

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the accompanying drawings required by the embodiments or prior art description will be briefly introduced as follows. Obviously, the drawings are only for the purpose of illustrating the embodiments of the present application, and for those skilled in the art, other drawings can also be obtained on the basis of these drawings without creative labor.

[0040] Figure 1 A schematic diagram of a prior art channel conflict;

[0041] Figure 2 A flowchart provided by an embodiment of the ultrasonic ranging method of the present application;

[0042] Figure 3 A schematic diagram of not performing time domain compression provided by an embodiment of the ultrasonic ranging method of the present application;

[0043] Figure 4 A schematic diagram of time domain compression provided by an embodiment of the ultrasonic ranging method of the present application;

[0044] Figure 5 A schematic diagram of conflict detection and resolution provided by an embodiment of the ultrasonic ranging method of the present application;

[0045] Figure 6 A schematic diagram of related peak offset provided by an embodiment of the ultrasonic ranging method of the present application;

[0046] Figure 7 A schematic diagram of ultrasonic signal processing provided by an embodiment of the ultrasonic ranging method of the present application;

[0047] Figure 8 A schematic diagram of the overall structure provided by an embodiment of the ultrasonic ranging method of the present application.

[0048] The purpose of the present application, functional characteristics and advantages will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0049] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application, and are not used to limit the present application.

[0050] In order to better understand the technical solutions of the present application, the following will be described in detail in combination with the drawings and specific embodiments of the specification.

[0051] Against the backdrop of the rapid development of the Internet of Things (IoT) and ubiquitous computing, ultrasonic ranging systems with distributed coordination of multiple devices are becoming an important research direction in the field of intelligent sensing. Compared to centralized architectures that rely on central control nodes, distributed coordination systems, through autonomous device decision-making and local coordination, are better able to adapt to dynamic and open environments, demonstrating unique application advantages in complex scenarios.

[0052] For example, in augmented reality scenarios, when multiple users' head-mounted displays (HMDs) build a spatial perception network using ultrasonic signals and remote controls, the HMDs struggle to rely on a central node for centralized coordination, leading to the formation of multiple independent distributed ranging subsystems. In enterprise office scenarios, multiple terminal devices with ranging-based user status recognition capabilities are constrained by a lack of cross-system coordination and can only rely on local decision-making to complete recognition tasks. In medical monitoring scenarios, multiple mobile medical devices establish distance links with different users' smart terminals to track them. In many cases, these scenarios, due to high device density, highly dynamic environments, and limited resources, make centralized coordination between the multiple distributed systems within the scenario impossible.

[0053] Achieving efficient and reliable distributed ranging without relying on global coordination hinges on minimizing channel conflicts between distributed systems. Channel conflicts arise when distributed systems lack information about channel resource allocation and lack centralized coordination. This means that multiple distributed systems use the same coded signal and cannot distinguish between them. This leads to incorrect distance calculations due to the inability to distinguish signal sources.

[0054] The traditional carrier sense mechanism is a classic collision avoidance scheme. Its core principle is to continuously sense the channel status and check whether the channel is idle before a node (receiving or transmitting) sends data. If the channel is idle, the signal is transmitted immediately. If the channel is occupied, a random backoff delay mechanism is initiated to avoid collisions. However, the traditional carrier sense mechanism, with its fixed sensing period of several seconds or even tens of seconds, is difficult to adapt to the instantaneous transmission characteristics of ultrasonic ranging pulses.

[0055] The time slot reservation mechanism is another existing conflict avoidance scheme that relies on a dedicated out-of-band negotiation channel and is a centralized pre-allocation model. However, this centralized pre-allocation model fundamentally conflicts with the core principles of distributed systems, which rely on autonomous decision-making and local coordination.

[0056] The above-mentioned traditional conflict avoidance mechanism is difficult to adapt to the short-term instantaneous characteristics of ultrasonic signals, and does not conform to the principle of autonomous coordination of distributed systems.

[0057] Therefore, the use of multi-channel coding schemes has become a key way to reduce the probability of collisions. Although multiplexing technologies (time division multiplexing, frequency division multiplexing, and code division multiplexing) can realize the parallel transmission of multiple ultrasonic signals, they still have limitations. Among them, time division multiplexing technology relies on strict time slice allocation. This allocation mechanism requires centralized coordination, which is contrary to the principle of autonomy of distributed systems. Although frequency division multiplexing technology uses the available frequency band of 18kHz-24kHz to divide orthogonal sub-channels, it is limited by the narrow bandwidth and the actual number of orthogonal sub-channels that can be supported does not exceed 4. In addition, the environmental Doppler effect will cause subcarrier offset, resulting in frequency band overlap, further reducing channel isolation. Code division multiplexing technology is based on pseudo-random sequences to distinguish devices. Due to the pseudo-orthogonality of the modulation signal, the number of optional codes is still limited, which makes it difficult to meet the needs of large-scale distributed scenarios.

[0058] like Figure 1 As shown, Figure 1 This paper shows an existing channel conflict case. In the same space, device 1 and device 2 are performing ranging, while device 3 and device 4 are also performing ranging. However, the two groups of ranging devices are unaware of each other, i.e., device 1 and device 2 are unaware that device 3 and device 4 are also performing ranging. In one case, device 1 and device 2, and device 3 and device 4, select the same or similar coding signal when performing ranging, i.e., Figure 1 As shown, device 1 receives a signal from device 4 or device 3 receives a signal from device 2; in the case of such a conflict, the devices will calculate an incorrect distance because they cannot distinguish the signal sources.

[0059] In order to solve the above problems, this application proposes an ultrasonic ranging method:

[0060] According to at least one of the following methods: (a) randomly arranging orthogonal code elements in the time domain; (b) adjusting the code element interval between adjacent code elements in the random arrangement result of the orthogonal code elements; (c) combining the random arrangement and the adjustment of the code element interval between adjacent code elements to generate a large number of candidate sequence codes, which greatly increases the ranging signal selection space of the distributed system and avoids signal collisions between distributed systems (the transmitting end and the receiving end can be regarded as a distributed system) to a large extent; the receiving end performs precise conflict suppression through conflict detection to realize conflict-resistant distributed ranging.

[0061] It should be noted that the execution subject of this embodiment can be an ultrasonic ranging system, or a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, mobile phone, etc., or an electronic device or processor capable of implementing the above functions. The following describes this embodiment and the following embodiments using an ultrasonic ranging system as an example.

[0062] Based on this, the embodiment of the present application provides an ultrasonic ranging method, referring to Figure 2 , Figure 2 This is a flow chart of an embodiment of the ultrasonic ranging method of the present application.

[0063] In this embodiment, the ultrasonic ranging method includes steps S10 to S30:

[0064] Step S10: generating multiple candidate sequence codes compressed in the time domain based on the orthogonal symbols, wherein generating multiple candidate sequence codes compressed in the time domain based on the orthogonal symbols comprises at least one of the following methods: (a) randomly permuting the orthogonal symbols in the time domain to form candidate sequence codes; (b) adjusting the symbol spacing between adjacent symbols in the random permutation result of the orthogonal symbols to form candidate sequence codes; (c) combining random permutation and symbol spacing adjustment between adjacent symbols to form candidate sequence codes;

[0065] It should be noted that orthogonal symbols refer to a group of basic signal units that do not interfere with each other. Time domain compression refers to compressing multiple symbols into a shorter time for transmission by shortening the symbol interval between adjacent symbols.

[0066] The candidate sequence encoding is generated by repeating or replacing orthogonal code elements in a specific or random order. In this embodiment, the arrangement of orthogonal code elements is not limited, forming encoding sequences with different time domain structures. For example, if 0 / 1 is selected as the orthogonal code element, one arrangement result may be: 11001010. In the arranged code element sequence, the code element interval between adjacent code elements may also be adjusted to be uniform or non-uniform. For example, the sequence encoding with adjusted code element interval may be: 1__1__0_0__1__0__1__0.

[0067] For example, multiple candidate sequence codes may be generated by randomly arranging only the orthogonal code elements in the time domain, or by adjusting only the code element interval between adjacent code elements. Alternatively, multiple candidate sequence codes may be generated by both randomly arranging the code elements in the time domain and adjusting the code element interval between adjacent code elements. This embodiment does not limit the method for generating the candidate sequence codes.

[0068] like Figure 3 As shown, Figure 3 A sequence coding without time domain compression is shown, e.g. Figure 4 As shown, Figure 4This demonstration demonstrates sequence coding using time-domain compression. By comparing multiple symbols and compressing them for transmission within a shorter timeframe, signal transmission efficiency can be improved. By compressing multiple symbols in the time domain, the resulting sequence code is no longer than two symbols, while maintaining information transmission capacity. Experiments have shown that while time compression reduces the transmission energy of a single symbol, overall signal quality does not significantly decrease.

[0069] It is understandable that, in step S10, a large number of candidate codes are generated through flexible arrangement and interval adjustment, which provides a basis for the subsequent selection of target sequence codes, thereby reducing the probability of signal conflicts between multiple devices.

[0070] Step S20, selecting a target sequence code from a plurality of candidate sequence codes, and sharing the target sequence code with a receiving end;

[0071] It should be noted that the transmitter randomly selects a target sequence code from a library of candidate codes and then shares it with the receiver. For example, code sharing with the receiver can be accomplished by pre-transmitting the target code's permutation rules and spacing patterns using low-frequency wireless communication. Alternatively, a consistent target sequence code can be generated using an encryption algorithm within an encrypted channel, enabling decentralized code synchronization.

[0072] It can be understood that step S20 ensures that the sending end and the receiving end reach a consensus on the uniqueness of the target code in a distributed scenario, thereby avoiding ranging failure caused by code mismatch.

[0073] Step S30 : broadcasting a target ultrasonic signal containing a target sequence code to a receiving end, receiving the target ultrasonic signal returned by the receiving end, and determining a distance to the receiving end based on the target ultrasonic signal.

[0074] It should be noted that the transmitter converts the target sequence code into a target ultrasonic signal and broadcasts it. The uniqueness of the target code filters out interference signals from other devices, ensuring ranging accuracy. After receiving the target ultrasonic signal from the receiver, the transmitter can determine the distance to the receiver based on the timestamp of the target ultrasonic signal. For specific ranging methods, see the receiver's embodiment.

[0075] It can be understood that step S30, by encoding and broadcasting the ultrasonic signal, can achieve accurate ranging in a distributed environment and is compatible with multi-device collaboration in dynamic scenarios.

[0076] In a feasible implementation, orthogonal code elements are signals that are orthogonal to each other in the frequency domain or the code domain. The orthogonal code elements are orthogonal to each other in the code domain and can utilize code division multiplexing and adopt relatively classic code division signals in the field of communication or signal processing, such as ZC sequence, pseudo-random sequence, linear frequency modulation signal, etc.

[0077] It should be noted that, since current multiplexing technology supports relatively few channel options for ultrasonic signals, relying solely on traditional multiplexing technology cannot meet the need to avoid channel conflicts as much as possible in distributed concurrent ranging scenarios. Based on the problems existing in the existing technology, this application designs code elements in the time domain through operations such as repetition and replacement, and also considers the selection of code elements. Since it is hoped that the code elements have sufficient bandwidth to cope with complex signal transmission environments, the code elements are generally selected to support code division multiplexing technology with strong autocorrelation and weak cross-correlation, that is, with orthogonal characteristics.

[0078] Orthogonal symbols with orthogonal properties include two symbols (the first symbol and the second symbol). This means that when selecting orthogonal symbols, two symbols, one symbol, or more symbols can be selected, with no limit on the number of symbols. The time-frequency traces of the first and second symbols mirror each other, causing the integral of the two symbol signals after multiplication in the time domain to approach zero, thus achieving strong differentiation between the signals. This orthogonal property enables the receiver to accurately separate the two symbols through matched filtering, significantly improving the anti-interference capability and multipath mitigation effect of multi-device parallel communication in ultrasonic ranging.

[0079] In this embodiment, at least one of the following methods is used: (a) orthogonal code elements are randomly arranged in the time domain; (b) the code element interval between adjacent code elements is adjusted in the random arrangement result of the orthogonal code elements; (c) a large number of candidate sequence codes are generated by combining random arrangement and code element interval adjustment between adjacent code elements, thereby breaking through the number limitation of traditional code division multiplexing codes and significantly reducing the probability of channel collisions; by randomly selecting the target sequence code and pre-synchronizing it with the receiving end, decentralized code allocation is achieved, avoiding the resource overhead of centralized coordination, and ensuring code differentiation between different systems.

[0080] Based on the above embodiment of the present application, in another embodiment of the present application, the same or similar contents as the above embodiment can be referred to the above introduction and will not be repeated hereafter. The ultrasonic ranging method further includes steps D10 to D20:

[0081] Step D10: Receive at least one ultrasonic signal, and when a target ultrasonic signal matching a target sequence code is identified, perform conflict detection on a transmission channel of the target ultrasonic signal under multiple decisions, wherein the target sequence code is selected from candidate sequence codes formed according to at least one of the following methods: (a) randomly permuting orthogonal symbols in the time domain; (b) adjusting the symbol spacing between adjacent symbols in the random permutation result of the orthogonal symbols; (c) combining random permutation and symbol spacing adjustment between adjacent symbols, wherein the transmitting end and the receiving end pre-share the target sequence code, and conflicts include coverage conflicts, congestion conflicts, and channel conflicts.

[0082] It should be noted that after the receiving end captures at least one ultrasonic signal, it first identifies the matching target ultrasonic signal from multiple ultrasonic signals through the target sequence code shared in advance with the transmitting end, and then performs conflict detection under multiple decisions on the transmission channel of the target ultrasonic signal; wherein, the target sequence code is generated by orthogonal code elements through time domain arrangement, adjustment of adjacent code element intervals, combined execution of random arrangement and code element interval adjustment between adjacent code elements, at least one method; the conflict types include coverage conflict, congestion conflict and channel conflict. Coverage conflict refers to the inability of the receiving end to detect the target ultrasonic signal due to excessive interference or missed transmission by the transmitting end; congestion conflict refers to the signal receiving end incorrectly identifying the target sequence code due to a complex environment, multiple distributed subsystems for concurrent ranging, and poor signal transmission conditions; channel conflict refers to different distributed subsystems simultaneously selecting the same sequence code and broadcasting signals simultaneously in a short period of time. The receiving end cannot identify the target ultrasonic signal transmitted by the transmitting end, and the multipath characteristics of the signal do not conform to the law of sound wave reflection.

[0083] In a feasible embodiment, after the step of receiving at least one ultrasonic signal in step D10, the method further includes:

[0084] If the target sequence code is not identified in each ultrasonic signal, it is determined to be a coverage conflict, and the transmitting end is notified to resend the target ultrasonic signal containing the target sequence code.

[0085] It should be noted that if the receiving end fails to detect the target sequence code among all received ultrasonic signals (i.e., it cannot identify the target ultrasonic signal that matches the target sequence code through matched filtering), it determines a coverage conflict. In this case, the receiving end immediately sends a retransmission instruction to the transmitting end, requesting it to retransmit the target ultrasonic signal.

[0086] Step D10, performing conflict detection on the transmission channel of the target ultrasonic signal under multiple decisions, includes steps E10 to E20:

[0087] Step E10: If no coverage conflict occurs and the peak-to-average ratio of the target ultrasonic signal is lower than a preset peak-to-average ratio threshold, it is determined to be a congestion conflict, and the transmitting end is notified to retransmit the target ultrasonic signal containing the target sequence code;

[0088] It should be noted that, when no coverage conflict occurs, if the peak-to-average ratio (peak value to average value) of the target ultrasonic signal falls below a preset threshold, a congestion conflict is detected. A low peak-to-average ratio indicates the presence of multiple devices transmitting the same frequency signal in the channel, causing waveform distortion and a sudden drop in the signal-to-noise ratio. In this case, the receiver notifies the transmitter to retransmit the target ultrasonic signal with a random delay, thus distributing the signal transmission time and reducing the probability of channel congestion.

[0089] In step E20, if no congestion conflict occurs and the relative relationship between the arrival time difference between the first target ultrasonic signal and the second target ultrasonic signal and the signal strength of the first target ultrasonic signal and the second target ultrasonic signal does not conform to the law of sound wave reflection, it is determined to be a channel conflict, and the transmitting end is notified to reselect the target sequence code and generate a new target ultrasonic signal for broadcast.

[0090] It should be noted that, when no congestion conflict occurs, if the relative relationship between the arrival time difference and the signal strength of the first target ultrasonic signal and the second target ultrasonic signal deviates from the acoustic wave reflection law, it is determined to be a channel conflict;

[0091] Among them, the first target ultrasonic signal can be a signal that reaches the receiving end directly without passing through an obstacle, with a short propagation time and high signal strength. The second target ultrasonic signal can be a signal that reaches the receiving end after being reflected by an obstacle, with a long propagation time and low signal strength. In an ideal environment, the relative relationship between the arrival time difference and the signal strength should satisfy the following requirements: the time difference is proportional to the path difference; and the signal strength is inversely proportional to the path length.

[0092] The relative relationship between the signal intensities of the first target ultrasonic signal and the second target ultrasonic signal does not conform to the law of sound wave reflection: the arrival time difference between the two target ultrasonic signals may be large, but the difference in the intensities of the two target ultrasonic signals is small; or the difference in the intensities of the two target ultrasonic signals may be significant, but the arrival time difference between the two target ultrasonic signals does not conform to the calculated sound speed value.

[0093] For example, the arrival time difference ΔT between two target ultrasonic signals is small, but the target ultrasonic signal strength difference ΔR is large, which violates the physical law that "the longer the distance, the greater the attenuation and the longer the propagation time", and is determined to be a channel conflict.

[0094] This type of conflict is primarily caused by multipath effects (e.g., sound waves reflecting off walls create false paths). The receiver notifies the transmitter to change the target sequence encoding (e.g., by switching the time-domain compression mode or spacing rule). By regenerating an orthogonal symbol arrangement or adjusting the symbol spacing, channel occupancy conflicts are avoided, thereby restoring channel reliability.

[0095] For example, Figure 5 As shown, Figure 5 A schematic diagram of conflict detection and resolution is shown. After receiving at least one ultrasonic signal, the receiver performs conflict detection. First, it checks for coverage conflicts. If so, it notifies the transmitter to retransmit the target ultrasonic signal with a random delay. It then checks for congestion conflicts. If so, it notifies the transmitter to retransmit the target ultrasonic signal with a random delay. It then checks for channel conflicts. If so, it notifies the transmitter to reselect the target sequence code and generate a new target ultrasonic signal. If no conflict is detected, it calculates the distance between the transmitter and receiver and outputs the distance value.

[0096] In this embodiment, when the target sequence code is completely unrecognized, it is determined to be environmental noise or strong interference coverage, triggering a signal retransmission mechanism to avoid ranging failure caused by the loss of the target ultrasonic signal; when the target ultrasonic signal exists but the peak-to-average ratio is lower than the threshold, it is determined to be channel congestion caused by the concurrency of multiple devices, and signal transmission is dispersed through random delay retransmission to reduce signal superposition interference; when the relationship between the arrival time difference and intensity of the target ultrasonic signal is abnormal, it is determined to be code duplication or illegal occupation, and the target sequence code is replaced to avoid channel conflicts and ensure code uniqueness; through a hierarchical conflict detection and conflict response mechanism, prone conflicts are resolved first, reducing unnecessary code switching overhead, and significantly improving the reliability and adaptability of the distributed ultrasonic ranging system.

[0097] Step D20: If a conflict is detected, a conflict resolution decision is triggered under the corresponding conflict; if no conflict is detected, the receiving end and the transmitting end are ranged based on the target ultrasonic signal.

[0098] It should be noted that after conflict detection, if there is no conflict in the current channel or the conflict in the channel is resolved, the distance between the receiving end and the transmitting end is measured based on the target ultrasonic signal.

[0099] In this embodiment, the target sequence coding generated based on the time domain arrangement and interval adjustment of orthogonal code elements reduces the probability of channel conflicts between multiple devices; through the judgment logic of coverage conflict, congestion conflict, and channel conflict, conflicts are accurately identified and differentiated conflict resolution strategies are triggered to achieve decentralized autonomous coordination.

[0100] The Doppler effect refers to the shift in the frequency of a received ultrasonic signal when there is relative motion between the transmitting device (the transmitter) and the receiving device (the receiver). Specifically, when the transmitting device moves toward the receiving device, the received signal frequency will be higher than the transmitted frequency; conversely, when the transmitting device moves away from the receiving device, the received signal frequency will be lower than the transmitted frequency. This frequency shift can be expressed as:

[0101] ;

[0102] in, is the signal frequency of the ultrasonic signal, is the signal frequency of the received ultrasonic signal, is the propagation speed of sound waves in the medium, is the movement speed of the receiving device, The movement speed of the sending device.

[0103] Since frequency offset introduces additional channel response offset, reducing the accuracy of ranging that relies on signal propagation time, the Doppler effect can cause serious ranging errors in sound signal ranging.

[0104] The traditional method of eliminating the Doppler effect is to use multi-dimensional information to calculate the frequency offset amplitude or device movement speed and compensate for the received signal, which will bring additional system overhead.

[0105] This application proposes a new method for eliminating the Doppler effect. In a feasible implementation, the method includes steps G10 to G30 before step D20:

[0106] Step G10, identifying a time-domain forward shift feature of a first symbol correlation peak and a time-domain backward shift feature of a second symbol correlation peak;

[0107] It should be noted that when the transmitter and receiver are relatively close, the Doppler effect causes the signal wavelength to be compressed, the received signal frequency to increase, and the first symbol correlation peak in the time domain appears to be shifted forward (the peak appears earlier than expected); when the transmitter and receiver are relatively far away, the Doppler effect causes the signal wavelength to be stretched, the received signal frequency to decrease, and the second symbol correlation peak in the time domain appears to be shifted backward (the peak appears later than expected). Since the first symbol and the second symbol have orthogonal characteristics, the time domain offset direction caused by their Doppler frequency deviation is also opposite. Figure 6 As shown in the figure, the correlation peak shifts of the two codeword signals under the Doppler effect interference of different speeds are displayed. The left side is the first codeword, and its correlation peak is shifted forward in the time domain; the right side is the second codeword, and its correlation peak is shifted backward in the time domain.

[0108] It can be understood that step G10 provides complementary information for Doppler frequency offset estimation by comparing the time domain offset directions of the two code elements, thereby avoiding misjudgment of the offset direction of a single signal.

[0109] Step G20, calculating the Doppler frequency offset estimation amount at the relative moving speed between the transmitting end and the receiving end based on the time domain forward shift feature and the time domain backward shift feature;

[0110] It should be noted that by utilizing the fixed and independent characteristics of the autocorrelation peak shifts exhibited by two orthogonal code elements facing the same speed, the Doppler frequency offset estimate is calculated without relying on external sensors or complex motion models, thus reducing computational complexity.

[0111] Step G30: performing time delay compensation on the target ultrasonic signal according to the Doppler frequency offset estimation to eliminate the Doppler effect of the target ultrasonic signal.

[0112] It should be noted that the Doppler frequency offset estimation is used to eliminate the target ultrasonic signal propagation delay deviation caused by device movement.

[0113] In this embodiment, the time domain forward shift characteristics of the first codeword correlation peak and the time domain backward shift characteristics of the second codeword correlation peak are used to calculate the Doppler frequency offset estimate by taking the difference between the two time shifts, thereby overcoming the estimation error caused by a single signal offset direction. The ultrasonic signal propagation delay is then corrected based on the Doppler frequency offset estimate to eliminate the Doppler effect caused by the relative motion of the device, thereby eliminating the coding recognition error caused by the Doppler effect and the resulting ranging deviation. In addition, this application utilizes the fixed and independent characteristics of the autocorrelation peak offset exhibited by two orthogonal codewords at the same speed to calculate the Doppler frequency offset estimate, without relying on external sensors or complex motion models, which can reduce computational complexity.

[0114] In another embodiment, step D20 includes:

[0115] Obtain a first timestamp and a second timestamp when the transmitting end sends the target ultrasonic signal, wherein the first timestamp is the first time when the transmitting end records that the target ultrasonic signal is sent, and the second timestamp is the second time when the receiving end records that the target ultrasonic signal is received;

[0116] When returning the target ultrasonic signal to the transmitting end, obtaining a third timestamp and a fourth timestamp, wherein the third timestamp is a third time when the receiving end records that the target ultrasonic signal is sent, and the fourth timestamp is a fourth time when the transmitting end records that the target ultrasonic signal is received;

[0117] Calculating a propagation delay of the target ultrasonic signal based on a first difference between the fourth timestamp and the first timestamp, and a second difference between the third timestamp and the second timestamp;

[0118] The distance between the receiving end and the transmitting end of the ultrasonic signal is obtained based on the propagation delay and the propagation speed of the ultrasonic wave.

[0119] It should be noted that the first timestamp (T1) is the time when the transmitter records the target ultrasonic signal; the second timestamp (T2) is the time when the receiver records the signal. The third timestamp (T3) is the time when the receiver records the reply signal (i.e., the target ultrasonic signal). The fourth timestamp (T4) is the time when the transmitter records the target ultrasonic signal.

[0120] The first difference is the total time from the transmitter sending to the receiver receiving the target ultrasonic signal (T4 - T1); the second difference is the local time the receiver processes the signal (T3 - T2).

[0121] Propagation delay ; The distance between the receiving end and the sending end of the ultrasonic signal : , where v is the propagation speed of ultrasound (about 343 m / s at room temperature).

[0122] In this embodiment, the accuracy and reliability of ultrasonic ranging are significantly improved through a two-way timestamp interaction mechanism and precise propagation delay calculation.

[0123] In another embodiment, step D10 includes:

[0124] Performing filtering on the received ultrasonic signal to obtain a preprocessed ultrasonic signal;

[0125] Calculate a first channel response curve of the preprocessed ultrasonic signal and the first symbol and a second channel response curve of the second symbol;

[0126] Searching for a correlation peak combination matching the time domain distribution of the target sequence code from the first channel response curve and the second channel response curve based on the symbol interval after time domain compression while eliminating the mutual correlation interference between the first channel response curve and the second channel response curve;

[0127] According to the time domain position of the correlation peak combination and the consistency of the coding interval, the target ultrasonic signal that matches the time domain characteristics of the target sequence coding is determined.

[0128] It should be noted that due to the noise that will appear during the signal transmission process and the cross-correlation interference between mutually orthogonal code elements, the receiving end will first pass the ultrasonic signal through a high-pass filter after receiving it to remove most of the interference noise outside the signal frequency band. For example, the cutoff frequency of the high-pass filter can be set to 16kHz.

[0129] To extract the target sequence code from the received ultrasonic signal, the channel characteristics of the different symbol signals must be extracted from the preprocessed ultrasonic signal. Correlation results are calculated between the received signal and a pair of symbol signals. The signal matching the target sequence code is then identified from these two sets of correlation results. Because the selected pair of symbol signals is orthogonal, the location of each symbol can be found by searching for correlation peaks within the correlation results. For example, symbol 1 has correlation peaks at t1, t3, t5, and t6, while symbol 0 has correlation peaks at t2, t4, and t7. These two sets of correlation peaks can also be called two sets of correlation results. The resulting sequence code is 1010110.

[0130] However, when there are multiple unknown distributed systems in the environment transmitting multiple sequence coded signals at unknown times and with unknown intensities, there will be considerable cross-correlation interference between different code elements. Therefore, it is also necessary to use interference cancellation algorithms to significantly suppress the cross-correlation interference.

[0131] like Figure 7As shown, first, correlation results of different code elements are obtained to obtain two groups of correlation results; then, interference elimination is performed on the two groups of correlation results to make the correlation peak of the code element signal more prominent.

[0132] After filtering and interference elimination, the channel response curves of the two codeword signals are obtained to obtain the first channel response curve and the second channel response curve. The two channel response curves are then replaced by an array of the positions of the correlation peaks in the curves. Finally, the correlation peak combination that best matches the target ultrasonic signal is searched in the two arrays consisting of the time domain coordinates of the correlation peaks to find the target ultrasonic signal that matches the time domain characteristics of the target sequence encoding.

[0133] For example, the existing search method is to adopt a complete traversal, but this scheme needs to traverse all nodes in the array to detect any code element. When the sequence coding length is k, it has a time complexity of O(kmn), which may cause a lot of delay in complex environments.

[0134] To optimize time complexity, the search method employed in this application is as follows: Based on the increasing nature of the candidate coordinate arrays for the two code elements, a binary search algorithm is employed. First, each element of array A is traversed in ascending order. For each candidate array element A[i], the sequence code C (C consists of 0s and 1s) is traversed. The algorithm determines which candidate array to use for confidence determination based on the value of C[n]. Next, a binary search is used to find the first candidate coordinate that is greater than or equal to the theoretical coordinates of the code element. This candidate coordinate is then checked to see if it falls within the fuzzy range, thereby determining whether the code element is a successful match. For each successfully matched code element, the confidence of the virtual signal starting with A[i] is incremented by 1. At the end of traversing each element of A, the confidence level is used to determine whether the optimal result should be updated. Ultimately, the ultrasonic signal with the highest confidence level (using the oldest-first principle for equal confidence levels) is selected as the target ultrasonic signal.

[0135] It is understandable that since the target sequence code includes two dimensions when it is formed, one is composed of multiple code element signals compressed in the time dimension, and the other is the code element interval between multiple code element signals. At the receiving end, only when the code element signals of the ultrasonic signal are consistent in both dimensions is it considered a successful match, that is, the target ultrasonic signal is successfully found.

[0136] In this implementation, filtering effectively removes low-frequency noise, improving the signal-to-noise ratio (SNR) of the received signal. A cross-correlation algorithm is then used to calculate the channel response curves for the first and second symbols. This is combined with an interference cancellation algorithm to suppress cross-correlation interference, ensuring that the correlation peaks are prominent. Based on the symbol interval characteristics after time-domain compression, the channel response curve is searched for correlation peak combinations that strictly match the target sequence's coding time-domain distribution. This is achieved through dual verification of time-domain position deviation and coding interval consistency, improving the matching rate of the target ultrasonic signal. Multi-stage signal processing and anti-interference design significantly improve the ultrasonic ranging system's signal recognition accuracy and ability to resist environmental interference.

[0137] For example, in order to help understand the implementation process of the ultrasonic ranging method obtained by combining this embodiment with the above embodiments, please refer to Figure 8 , Figure 8 A schematic diagram of the overall structure of an ultrasonic ranging method is provided, specifically:

[0138] Mobile phones and laptops can be both transmitters and receivers; the transmitter generates a target ultrasonic signal carrying a target sequence code, wherein the target sequence code is generated by at least one of the following methods: arranging orthogonal code elements in the time domain, adjusting the interval between adjacent code elements, combining random arrangement and adjusting the interval between adjacent code elements, and has uniqueness and anti-interference characteristics. The transmitter and receiver use an inter-device communication link to synchronize the target sequence code in real time. When the transmitter broadcasts the ultrasonic signal carrying the target sequence code to the receiver, the receiver receives and processes the signal and matches the processed signal with the target sequence code. If the sequence codes are completely matched and there is no conflict, the distance between the receiver and the transmitter of the ultrasonic signal is directly calculated and the distance value is output; if a conflict is detected, the conflict determination logic is used to accurately identify the conflict and trigger a differentiated conflict resolution strategy to achieve decentralized autonomous coordination.

[0139] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the ultrasonic ranging method of the present application. More forms of simple transformations based on this technical concept, such as the interaction and combination of various embodiments, are all within the scope of protection of the present application.

[0140] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, a computer program) stored thereon, and the computer-readable program instructions are used to execute the ultrasonic ranging method in the above embodiment.

[0141] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems or devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0142] Computer program code for performing the operations of the present application may be written in one or more programming languages, or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0143] The flow charts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, program segment or a part of code, and the module, program segment or a part of code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order than that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented by a dedicated hardware-based system that performs the specified function or operation, or can be implemented by a combination of dedicated hardware and computer instructions.

[0144] The modules described in the embodiments of the present application may be implemented in software or hardware, wherein the name of a module does not necessarily limit the unit itself.

[0145] The computer-readable storage medium provided in this application stores computer-readable program instructions (i.e., a computer program) for executing the aforementioned ultrasonic ranging method. This computer-readable storage medium can address the channel conflicts faced by existing technologies in distributed ultrasonic ranging scenarios, which hinders their ability to meet the requirements of large-scale distributed systems. Compared to existing technologies, the beneficial effects of the computer-readable storage medium provided in this application are similar to those of the ultrasonic ranging method provided in the aforementioned embodiments, and are not further elaborated here.

[0146] The present application also provides a computer program product, comprising a computer program, which implements the steps of the ultrasonic ranging method as described above when the computer program is executed by a processor.

[0147] The computer program product provided in this application can address the channel conflict issues faced by existing technologies in distributed ultrasonic ranging scenarios, making it difficult to meet the requirements of large-scale distributed systems. Compared with existing technologies, the beneficial effects of the computer program product provided in this application are the same as those of the ultrasonic ranging method provided in the above-mentioned embodiments, and will not be elaborated here.

[0148] The above description is only part of the embodiments of the present application and does not limit the patent scope of the present application. All equivalent structural transformations made by using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. An ultrasonic ranging method, characterized in that: Applied to the receiving end, the ultrasonic ranging method includes: Receive at least one ultrasonic signal, and after the step of receiving at least one ultrasonic signal, further include: if the target sequence code is not identified in each ultrasonic signal, it is determined to be a coverage conflict, and the transmitting end is notified to retransmit the target ultrasonic signal containing the target sequence code; when the target ultrasonic signal matching the target sequence code is identified, the transmission channel of the target ultrasonic signal is subjected to conflict detection under multiple decisions, and the step of performing conflict detection on the transmission channel of the target ultrasonic signal under multiple decisions includes: if the coverage conflict does not occur and the peak-to-average ratio of the target ultrasonic signal is lower than a preset peak-to-average ratio threshold, it is determined to be a congestion conflict, and the transmitting end is notified to retransmit the target ultrasonic signal containing the target sequence code; if the congestion conflict does not occur and the first target ultrasonic signal When the relative relationship between the arrival time difference of the first target ultrasonic signal and the second target ultrasonic signal and the signal strength of the second target ultrasonic signal does not conform to the law of sound wave reflection, it is determined to be a channel conflict, and the transmitting end is notified to reselect the target sequence code and generate a new target ultrasonic signal for broadcast; wherein, the target sequence code is selected from the candidate sequence codes formed according to at least one of the following methods: (a) randomly arranging orthogonal code elements in the time domain; (b) adjusting the code element interval between adjacent code elements in the random arrangement result of the orthogonal code elements; (c) combining the random arrangement and the code element interval adjustment between adjacent code elements, the transmitting end and the receiving end pre-share the target sequence code, and the conflict includes coverage conflict, congestion conflict and channel conflict; If a conflict is detected, a conflict resolution decision is triggered under the corresponding conflict; if no conflict is detected, the distance between the receiving end and the transmitting end is measured based on the target ultrasonic signal.

2. The method according to claim 1, wherein The orthogonal code element includes a first code element and a second code element, and before the step of performing distance measurement on the receiving end and the transmitting end based on the target ultrasonic signal, the step further includes: Identify the time domain forward shift feature of the first symbol correlation peak and the time domain backward shift feature of the second symbol correlation peak; Calculating a Doppler frequency offset estimate at a relative moving speed between a transmitting end and a receiving end according to the time domain forward shift feature and the time domain backward shift feature; Time delay compensation is performed on the target ultrasonic signal according to the Doppler frequency offset estimation to eliminate the Doppler effect of the target ultrasonic signal.

3. The method according to claim 1, wherein The step of measuring the distance between the receiving end and the transmitting end based on the target ultrasonic signal includes: Obtain a first timestamp and a second timestamp of the target ultrasonic signal sent by the transmitting end, wherein the first timestamp is the first time when the transmitting end records that the target ultrasonic signal is sent, and the second timestamp is the second time when the receiving end records that the target ultrasonic signal is received; When returning the target ultrasonic signal to the transmitting end, obtaining a third timestamp and a fourth timestamp, wherein the third timestamp is a third time recorded by the receiving end when the receiving end sends the target ultrasonic signal, and the fourth timestamp is a fourth time recorded by the transmitting end when the transmitting end receives the target ultrasonic signal; Calculating a propagation delay of a target ultrasonic signal based on a first difference between the fourth timestamp and the first timestamp, and a second difference between the third timestamp and the second timestamp; The distance between the receiving end and the transmitting end of the ultrasonic signal is obtained according to the propagation delay and the propagation speed of the ultrasonic wave.

4. The method according to claim 1, wherein The orthogonal code element includes a first code element and a second code element. After the step of receiving at least one ultrasonic signal, the method further includes: Performing filtering on the received ultrasonic signal to obtain a preprocessed ultrasonic signal; Calculating a first channel response curve of the preprocessed ultrasonic signal and a first code element and a second channel response curve of the second code element; Searching, from the first channel response curve and the second channel response curve based on the symbol interval after time domain compression, for a correlation peak combination that matches the time domain distribution of the target sequence code, while eliminating the mutual correlation interference between the first channel response curve and the second channel response curve; According to the time domain position of the correlation peak combination and the consistency of the coding interval, a target ultrasonic signal matching the time domain characteristics of the target sequence coding is determined.

5. An ultrasonic ranging system, characterized in that: The ultrasonic ranging system includes a transmitting end and a receiving end, and the receiving end is configured to implement the steps of the ultrasonic ranging method according to any one of claims 1 to 4.

6. A storage medium, characterized in that The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the ultrasonic ranging method according to any one of claims 1 to 4 are implemented.

7. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the ultrasonic ranging method according to any one of claims 1 to 4 are implemented.

Images