Single-sideband phase-sensitive detection method and system

Abstract

The present invention provides a single-sideband phase-sensitive detection method, system, device, storage medium, and computer program product, which relate to the technical fields of signal processing and signal amplification and can be applied to signal detection and other situations. Specifically, a target signal in a detection system is repeatedly triggered, the modulation phase of a modulated signal is changed at each trigger time, and the target signal triggered each time is modulated based on the modulated signal to obtain multiple sets of detection signals with different modulation phases. The multiple sets of detection signals are post-processed to obtain multiple sets of equivalent single-sideband modulated signals, and the multiple sets of equivalent single-sideband modulated signals are demodulated to obtain processed signals. This improves the signal detection bandwidth and sensitivity.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to Chinese Patent Application No. 202211082749.6 (Title: Signal Detection Method and System) filed on September 6, 2022, the entire contents of which are incorporated herein by reference. The present invention relates to the technical fields of signal processing and signal amplification, and is applicable to signal detection and other situations, and in particular to a single-sideband phase-sensitive detection method, system, device, storage medium and computer program product. [Background technology]

[0002] In scientific research, processing weak signals is very important, for example, magnetic resonance signal detection, infrared signal detection, radar signal detection are all weak signals that people are concerned about.

[0003] A lock-in amplifier is an amplifier that detects weak signals in a phase-sensitive manner. It is an effective method for detecting weak signals, significantly suppressing interference noise and improving the signal-to-noise ratio. The signal frequency typically detected by a lock-in amplifier is much smaller than the modulation frequency of the lock-in amplifier. When the detected signal contains a mutated signal and its subsequent evolution over a wide time domain, especially when the varying signal bandwidth is higher than the modulation frequency, traditional lock-in amplification technology cannot solve the problem. Therefore, high-sensitivity signal detection over a wide time domain is extremely difficult. Summary of the Invention

[0004] The present invention provides a Single-Sideband Phase-Sensitive Detection Method (SSB-PSD), a system, an apparatus, a storage medium, and a computer program product to improve the detection sensitivity of weak wideband signals.

[0005] According to one aspect of the present invention, there is provided a single-sideband phase-sensitive detection method including the steps of repeatedly triggering a target signal in a detection system and varying the modulation phase of the modulated signal at each trigger time; modulating the target signal triggered each time based on the modulated signal to obtain multiple sets of detection signals having different modulation phases; post-processing the multiple sets of detection signals to obtain multiple sets of equivalent single-sideband modulated signals; and demodulating the multiple sets of equivalent single-sideband modulated signals to obtain processed signals.

[0006] According to another aspect of the present invention, there is provided a single-sideband phase-sensitive detection system including: a timing controller used to control a modulated signal or trigger a target signal; a signal collector for acquiring a plurality of sets of detected signals having different modulation phases obtained by modulating the target signal repeatedly triggered by the modulated signal; and a signal processor for receiving the plurality of sets of detected signals acquired by the signal collector, post-processing the plurality of sets of detected signals to obtain a plurality of sets of equivalent single-sideband modulated signals, and demodulating the plurality of sets of equivalent single-sideband modulated signals to obtain processed signals.

[0007] According to another aspect of the present invention, there is provided an electronic device including at least one processor and a memory communicatively coupled to the at least one processor, wherein the memory stores instructions executable by the at least one processor, the instructions, when executed by the at least one processor, enable the at least one processor to perform the single-sideband phase-sensitive detection method.

[0008] According to another aspect of the present invention, there is provided a non-transitory computer-readable storage medium having stored thereon computer instructions for causing the computer to perform the single-sideband phase-sensitive detection method.

[0009] According to another aspect of the present invention, there is provided a computer program product including a computer program, the computer program being executed by a processor to implement the single-sideband phase-sensitive detection method.

[0010] It should be noted that the contents described herein are not intended to identify key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will be readily apparent from the following description. [Brief explanation of the drawings]

[0011] The drawings are provided for a better understanding of the invention and are not intended to limit the invention. [Figure 1] FIG. 1 is an exemplary system architecture diagram to which the present invention can be applied. [Figure 2] 1 is a flowchart of one embodiment of a single-sideband phase-sensitive detection method of the present invention. [Figure 3] 4 is a flowchart of another embodiment of the single-sideband phase-sensitive detection method of the present invention. [Figure 4] FIG. 2 is a schematic diagram of phase control for a detection signal according to the present invention. [Figure 5] 2 is a schematic diagram of the signal spectrum of the single-sideband phase-sensitive detection method of the present invention; FIG. [Figure 6] 3 is a schematic diagram of a signal after acquisition processing of the present invention; FIG. [Figure 7] 2 is a schematic diagram of a processed signal obtained by the single-sideband phase-sensitive detection method of the present invention; [Figure 8] FIG. 2 is a schematic diagram of a processed signal obtained by a direct sampling method. [Figure 9] 1 is a structural schematic diagram of an embodiment of a single-sideband phase-sensitive detection system of the present invention; [Figure 10] FIG. 2 is a block diagram of an electronic device for implementing a single-sideband phase-sensitive detection method according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. Various details in the embodiments of the present invention are for the purpose of understanding the present invention and are exemplary. Therefore, those skilled in the art will understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Also, for the sake of clarity and conciseness, the following description will omit descriptions of well-known functions and configurations.

[0013] FIG. 1 illustrates an exemplary system architecture 100 in which an embodiment of the single-sideband phase-sensitive detection method of the present invention can be used.

[0014] 1, system architecture 100 may include terminal equipment 101, 102, a network 103, and a server 104. Network 103 is a medium for providing a communication link between terminal equipment 101, 102 and server 104. Network 103 may include various connection types, such as wired, wireless communication links, or fiber optic cables.

[0015] Users can use terminal equipment 101, 102 to interact with server 104 via network 103 to obtain detection signals, etc. The terminal equipment 101, 102 can perform timing control and analog signal control, and then convert the analog signal into a digital signal via a digital-to-analog converter, which can then be used to communicate with server 104 via network 103.

[0016] The terminal equipment 101, 102 may be hardware or software. If it is hardware, the terminal equipment 101, 102 may be various signal collection equipment, timing control equipment, electronic equipment, including but not limited to photoelectric signal sensors, laptops, desktop computers, etc. If it is software, the terminal equipment 101, 102 may be installed in the above electronic equipment, and may be realized as multiple software or software modules, or as a single software or software module, and is not limited thereto.

[0017] The server 104 can provide services based on signal processing. For example, the server 104 can analyze and process the detection signals acquired from the terminal equipment 101, 102 to generate processing results (e.g., determine the processed signals, etc.).

[0018] It should be noted that server 104 may be hardware or software. If it is hardware, server 104 may be implemented as a distributed server cluster consisting of multiple servers, or as a single server. If it is software, server 104 may be implemented as multiple software programs or software modules (e.g., providing distributed services) or as a single software program or software module, and is not limited thereto.

[0019] It is understood that the number of terminal equipments, networks and servers in Figure 1 is merely exemplary, and there can be any number of terminal equipments, networks and servers according to actual needs.

[0020] 2 shows a flowchart 200 of one embodiment of a single-sideband phase-sensitive detection method according to the present invention. The single-sideband phase-sensitive detection method includes the following steps:

[0021] Step 201: A target signal in a detection system is repeatedly triggered, and the modulation phase of the modulated signal at each trigger time is changed.

[0022] In this embodiment, the performer of the single-sideband phase-sensitive detection method can repeatedly trigger a target signal in the detected system and change the modulation phase of the modulated signal at each trigger time. Here, the target signal in the detected system can be repeatedly generated. In some specific physical systems, the target signal is extremely weak and cannot be directly detected, so it must be modulated based on the modulated signal to obtain the target signal. The target signal can be modulated multiple times based on the modulated signal. Specifically, the target signal can be repeatedly generated at multiple trigger times, and the time at which the target signal occurs can be controlled so that the modulated signal has a different modulation phase at each trigger time. Here, the modulation phase of the modulated signal at each trigger time changes according to a specific rule. For example, the distance between adjacent phases is π / 2n, where n is an integer. Alternatively, the modulation phase at each trigger time changes randomly throughout the cycle.

[0023] Step 202: Modulate the target signal triggered each time based on the modulating signal to obtain multiple sets of detection signals with different modulation phases.

[0024] In this embodiment, the executing entity determines multiple trigger times and then modulates the target signal triggered each time based on the modulation signal to obtain multiple sets of detection signals with different modulation phases. For example, the modulation of the target signal can be achieved by changing physical parameters such as the voltage, current, and magnetic field in the detection system. Specifically, the target signal generated at each trigger time is modulated based on the modulation signal at that trigger time, thereby obtaining and sampling the detection signal corresponding to that trigger time to obtain multiple sets of detection signals. Because the modulation signal has a different modulation phase at each trigger time, the obtained multiple sets of detection signals also have different modulation phases.

[0025] Step 203: Post-process the sets of detected signals to obtain sets of equivalent single-sideband modulated signals. In this embodiment, the above-mentioned implementation entity obtains multiple sets of detection signals, and then post-processes the multiple sets of detection signals to obtain multiple sets of equivalent single sideband modulated signals. Specifically, the multiple sets of detection signals can be high-pass filtered using any digital or hardware filter. That is, the modulation signal frequency is set as a frequency threshold, and all signals in each set of detection signals below the frequency threshold are cut off, and signals above the frequency threshold are retained, thereby obtaining multiple sets of filtered signals, and the multiple sets of filtered signals are determined as multiple sets of equivalent single sideband modulated signals.

[0026] The resulting detection signal contains various noise signals. 1 / f noise, which is widely present in nature, exhibits a distribution in which the lower the frequency, the greater the noise intensity. Therefore, to accurately detect the target signal, it is necessary to remove noise signals from the detection signal, especially low-frequency noise signals. The target signal contains lower and upper sideband signals because its frequency has been shifted to near the modulation frequency through modulation processing. By suppressing the lower sideband signal and retaining the upper sideband signal in the detection signal, noise can be removed and a wide bandwidth can be maintained.

[0027] Step 204: demodulating the sets of equivalent single sideband modulated signals to obtain processed signals;

[0028] In this embodiment, the execution entity acquires multiple sets of equivalent single sideband modulated signals, and then demodulates the multiple sets of equivalent single sideband modulated signals to obtain processed signals. Specifically, the execution entity acquires demodulated signals, demodulates the multiple sets of equivalent single sideband modulated signals based on the demodulated signals, and the demodulated signals are used as processed signals. Note that the demodulated signals may be acquired before performing step 201, or may be acquired after performing at least one of steps 201-203; this is not a limitation of the present invention. The demodulated signals may be acquired using signal acquisition equipment, and the frequency and phase of the modulated signals may be acquired, and then a signal may be generated by simulation to serve as the demodulated signal; this is not a limitation of the present invention. Here, the demodulated signals and the modulated signals have the same frequency and phase.

[0029] In the single-sideband phase-sensitive detection method provided in the embodiment of the present invention, first, a target signal in the detection system is repeatedly triggered, and the modulation phase of the modulated signal is changed at each trigger time. Then, the target signal is modulated based on the modulated signal each time it is triggered, thereby obtaining multiple sets of detection signals with different modulation phases. Next, the multiple sets of detection signals are post-processed to obtain multiple sets of equivalent single-sideband modulated signals. Finally, the multiple sets of equivalent single-sideband modulated signals are demodulated to obtain processed signals. By filtering noise with single-sideband filtering, most low-frequency noise in the detection signals is removed, thereby improving the accuracy of the processed signals. Furthermore, by filtering with single-sideband filtering, a wide bandwidth is preserved in the detection signals, preventing distortion or deformation of the variance signals in the detection signals. An advantage of the single-sideband phase-sensitive detection method of the present invention is that the width of the target signal can be larger than the width of the modulated signal.

[0030] 3 is a flowchart 300 of another embodiment of a single-sideband phase-sensitive detection method according to the present invention, which includes the following steps:

[0031] Step 301: The target signal in the detection system is repeatedly triggered, and the modulation phase of the modulated signal at each trigger time is changed.

[0032] In this embodiment, the specific operation of step 301 has been described in detail in step 201 in the embodiment shown in FIG. 2, so the description will be omitted here.

[0033] In some implementations of this embodiment, a continuous modulated signal can be acquired. The frequency of the trigger signal is determined based on the principle of aliasing between the modulated signal and the trigger signal. The trigger signal repeatedly triggers the target signal in the detection system, changing the modulation phase of the modulated signal at each trigger time.

[0034] Specifically, Figure 4 is a schematic diagram illustrating the phase control of a detection signal according to the present invention. As can be seen from Figure 4(a), a continuous modulated signal can be acquired, and the target signal in the detection system can be repeatedly generated based on the frequency of the trigger signal. The generated target signals are overlapping but not mutually overlapping. Based on the principle of aliasing between the modulated signal and the trigger signal, the trigger signal generation frequency can be determined, and the target signal can be repeatedly generated at multiple different trigger times. The modulated signal can have a different modulation phase at each trigger time, and the modulated signal can be controlled to generate multiple modulation phases at the multiple trigger times. This allows the repeated generation of the target signal at multiple different trigger times under the continuous modulated signal, and the repeatedly generated target signal can be modulated based on this continuous modulated signal to obtain multiple sets of detection signals. Because the modulated signal has a different modulation phase at each trigger time, the resulting multiple sets of detection signals also have different initial phases.

[0035] In some implementations of this embodiment, the trigger signal and the modulating signal of the target signal can be timed so that the modulating signal has different modulation phases at multiple trigger times of the trigger signal, and the trigger signal repeatedly triggers the target signal in the system being detected.

[0036] Specifically, referring to Figure 4, as can be seen from Figure 4(b), the trigger signal and modulating signal of the target signal are timing-controlled to generate multiple sets of modulating signals. Each time a trigger signal is generated, the multiple sets of modulating signals have different modulation phases at each trigger time. The generated multiple sets of modulating signals can be controlled to generate multiple modulation phases at many trigger times. This allows the target signal generated at each trigger time to be modulated based on a corresponding set of modulating signals to obtain a set of detection signals. This results in multiple sets of detection signals. Because each set of modulating signals has a different modulation phase, the resulting multiple sets of detection signals also have different initial phases.

[0037] Step 302: Modulate the target signal triggered each time based on the modulating signal to obtain a plurality of sets of detection signals with different modulation phases.

[0038] In this embodiment, the specific operation of step 302 has been described in detail in step 202 in the embodiment shown in FIG. 2 and step 301 in the embodiment shown in FIG. 3, so the description will be omitted here.

[0039] The obtained multiple sets of detection signals are at least two sets of detection signals. When multiple sets of detection signals are included, each detection signal has a corresponding other detection signal with a modulation phase shift of π / 2. When there are only two sets of detection signals, the phase difference between the modulation signals at the initial point of the two sets of detection signals is π / 2.

[0040] Step 303: High-pass filtering the sets of detected signals to obtain sets of filtered signals.

[0041] In this embodiment, the specific operation of step 303 has been described in detail in step 203 in the embodiment shown in FIG. 2, so the description will be omitted here.

[0042] Step 304: Perform Hilbert transform on the multiple sets of filtered signals to obtain multiple sets of transformed signals, and packetize and superimpose the multiple sets of filtered signals and the multiple sets of transformed signals to obtain multiple sets of equivalent single-sideband modulated signals.

[0043] In this embodiment, the executing entity obtains multiple sets of filtered signals, then performs Hilbert transform on the multiple sets of filtered signals to obtain multiple sets of transformed signals, and packetizes and superimposes the multiple sets of filtered signals and the multiple sets of transformed signals to obtain multiple sets of equivalent single sideband modulated signals. Specifically, the target signal is a periodically changing signal that can be divided into the sum of multiple cosine signals, and therefore the target signal can be expressed in the form of the following Fourier expansion:

number

[0044] Furthermore, f kin If (t) is expanded to complex space, it can be expressed in the following form:

number

[0045] Each modulation signal is also a periodically changing signal, and can be expressed in the form of a cosine signal as follows:

number

[0046] Furthermore, when f1(t) is expanded to the complex space, it can be expressed in the following form:

number

[0047] The modulation frequency is ω mod If , the initial modulation phase sampled at the kth time in the sampling direction is φ mod (k), and b is the linear modulation amplitude, which allows us to obtain a single-sideband modulated signal. The single-sideband modulated signal can be expressed as follows:

number

[0048] By expanding F(t,k), the real part of the signal can be expressed as follows:

number

number

[0049] Noise may be mixed into the signal during transmission. Due to the influence of noise, the detected signal may also contain a noise signal. The signal actually detected after modulation may also contain a noise signal, which is specifically expressed by the following formula:

number

number

[0050] The plurality of sets of filtered signals are subjected to Hilbert transform to obtain a plurality of sets of transformed signals. Here, Hilbert transform refers to performing a Hilbert operation on the filtered signals. This operation is for constructing the following parts of the equivalent single sideband modulated signal:

number

[0051] Select different sampling batches of signals from the multiple sets of filtered signals, and make them shift in phase from the modulation signal corresponding to the converted signal by π / 2. That is, the filtered signal modulation phase is φ mod (k') is the conversion signal modulation phase φ mod (k) has the following relationship:

number

[0052] This operation is to construct the following part of the equivalent single sideband modulated signal:

number

[0053] The filtered signals with a phase difference of π / 2 can be superimposed with the converted signals to obtain multiple sets of equivalent single-sideband modulated signals, as follows:

number

[0054] FIG. 5 is a schematic diagram of a signal spectrum for the single-sideband phase-sensitive detection method of the present invention. FIG. 5(a) shows a target signal. In some specific physical systems, the target signal is too weak to be detected directly. Therefore, the target signal can only be obtained by modulating it based on the modulating signal. FIG. 5(b) shows a detected signal. By repeatedly triggering the target signal in the detected system, changing the modulation phase of the modulating signal at each trigger time, and modulating the target signal each time based on the modulating signal, multiple sets of detected signals with different modulation phases can be obtained. As can be seen from FIG. 5(b), if the signal bandwidth is greater than twice the modulation frequency, an image signal will be generated in the detected signal. FIG. 5(c) shows an equivalent single-sideband modulated signal. If the signal bandwidth is greater than twice the modulation frequency, an image signal will be generated in the detected signal. Therefore, multiple sets of detected signals are high-pass filtered. The filtered signal cannot be determined as an equivalent single-sideband modulated signal. The multiple sets of filtered signals are subjected to Hilbert transform to obtain multiple sets of transformed signals, and the multiple sets of filtered signals and the multiple sets of transformed signals are packetized and superimposed to obtain multiple sets of equivalent single-sideband modulated signals, thereby obtaining accurate equivalent single-sideband modulated signals. Figure 5(d) shows the demodulated signal. After obtaining the equivalent single-sideband modulated signals, the multiple sets of equivalent single-sideband modulated signals are single-sideband demodulated based on the demodulated signals to obtain more accurate demodulated signals.

[0055] Alternatively, multiple sets of equivalent single-sideband modulated signals may be obtained by high-pass filtering multiple sets of detection signals to obtain multiple sets of filtered signals, then performing a Hilbert transform on the multiple sets of filtered signals to obtain multiple sets of converted signals, and packetizing and superimposing the multiple sets of filtered signals and the multiple converted signals. Alternatively, multiple sets of detection signals may be performed by Hilbert transforming multiple sets of converted signals to obtain multiple sets of converted signals, packetizing and superimposing the multiple sets of detection signals and the multiple converted signals, and then high-pass filtering the superimposed signals to obtain multiple sets of equivalent single-sideband modulated signals. This is not a limitation of the present invention.

[0056] In some alternative implementations of this embodiment, when the signal bandwidth is less than twice the modulation frequency, the sets of filtered signals are determined as sets of equivalent single-sideband modulated signals.

[0057] Specifically, in application scenarios where the signal bandwidth is less than twice the modulation frequency, the executing entity obtains multiple sets of filtered signals, then performs Hilbert transform on the multiple sets of filtered signals to obtain multiple sets of converted signals, and packetizes and superimposes the multiple sets of filtered signals and the multiple sets of converted signals to obtain multiple sets of equivalent single-sideband modulated signals, and can also directly determine the multiple sets of filtered signals as multiple sets of equivalent single-sideband modulated signals.

[0058] Step 305: Obtain the demodulated signal.

[0059] In this embodiment, the executing entity can acquire a demodulated signal. The demodulated signal may be acquired before performing step 301, or after performing at least one of steps 301-304, and this is not a limitation of the present invention. The demodulated signal may be acquired using a signal acquisition device, and the frequency and phase of the modulated signal may be acquired, and then a signal segment may be generated as the demodulated signal through simulation, and this is not a limitation of the present invention. Here, the demodulated signal and the modulated signal have the same frequency and initial phase.

[0060] Step 306: Single-sideband demodulate the plurality of sets of equivalent single-sideband modulated signals based on the demodulated signals to obtain a plurality of sets of demodulated signals.

[0061] In this embodiment, the executing entity can obtain a demodulated signal, and then demodulate a plurality of sets of equivalent single sideband modulated signals based on the demodulated signal to obtain a plurality of sets of demodulated signals.

[0062] In some alternative implementations of this embodiment, multiple sets of equivalent single sideband modulated signals can be filter demodulated based on the demodulated signal to obtain multiple sets of demodulated signals. Specifically, the demodulated signal is multiplied by each set of equivalent single sideband modulated signals to obtain multiple sets of first signals, and the multiple sets of first signals are low-pass filtered in the sampling direction to obtain multiple sets of demodulated signals.

[0063] Specifically, each set of equivalent single-sideband modulated signals can be multiplied by a demodulated signal having the same initial phase as the equivalent single-sideband modulated signal. Here, the sets of equivalent single-sideband modulated signals have different initial phases. The multiplied signal is then low-pass filtered in the sampling direction. That is, the sets of multiplied signals with different initial phases are low-pass filtered at the same time point but at different sampling times. By using the sampling direction filtering method instead of the traditional time-domain filtering method, a signal with high time resolution can be obtained.

[0064] The k-th set of equivalent single-sideband modulated signals in the sampling direction is expressed by the following equation:

number

[0065] The demodulated signals can be multiplied by each set of equivalent single-sideband modulated signals, and the resulting first signal of the kth set can be expressed as follows:

number

[0066]

number

number

[0067] In some selectable implementation methods of this embodiment, after obtaining multiple sets of first signals, the execution body can also perform low-pass filtering on the multiple sets of first signals in the time axis direction according to the signal band being less than twice the modulation frequency, to obtain multiple sets of demodulated signals.

[0068] Specifically, in an application scenario where the signal band is smaller than twice the modulation frequency, the executing entity may obtain a plurality of sets of first signals, and then perform low-pass filtering on the plurality of sets of first signals in the sampling direction to obtain a plurality of sets of demodulated signals, or may multiply the demodulated signals by respective sets of equivalent single-sideband modulated signals, and perform low-pass filtering on the plurality of sets of multiplied signals in the time axis direction to obtain a plurality of sets of demodulated signals. Here, the plurality of sets of multiplied signals can be low-pass filtered using any digital filter or hardware filter.

[0069] In some alternative implementations of this embodiment, multiple sets of equivalent single-sideband modulated signals can be phase-shift demodulated based on the demodulated signals to obtain multiple sets of demodulated signals. Specifically, the demodulated signals can be multiplied by respective sets of equivalent single-sideband modulated signals to obtain multiple sets of second signals, the demodulated signals can be phase-shifted to obtain phase-shifted demodulated signals, the multiple sets of equivalent single-sideband modulated signals can be Hilbert transformed to obtain multiple sets of third signals, the phase-shifted demodulated signals can be multiplied by respective sets of third signals to obtain multiple sets of fourth signals, and the multiple sets of second signals can be superimposed with the multiple sets of fourth signals to obtain multiple sets of demodulated signals.

[0070] Phase-shift demodulation involves the superposition of two signals: the product of the demodulated signal with the equivalent single-sideband modulated signal, and the product of the demodulated signal after a π / 2 phase shift with the Hilbert transform of the equivalent single-sideband modulated signal.

[0071] Step 307: Multiple sets of demodulated signals are superimposed and averaged to obtain a processed signal.

[0072] In this embodiment, the execution body obtains multiple sets of demodulated signals, superimposes the multiple sets of demodulated signals to obtain a superimposed signal, and then averages the superimposed signal to obtain a processed signal. By superimposing multiple sets of demodulated signals, noise can be effectively removed as the data volume increases, and the signal-to-noise ratio of the processed signal can be improved.

[0073] After demodulating the equivalent single-sideband modulated signal, two signals are obtained. The real part signal is the I channel signal, and the imaginary part signal is the Q channel signal. After processing using the above processing method, the I channel signal is obtained. The I channel is the processed signal. After the demodulated signal undergoes a π / 2 phase shift, the Q channel signal is obtained by performing the same processing.

[0074] As can be seen from Figure 3, compared with the embodiment corresponding to Figure 2, the single-sideband phase-sensitive detection method in this embodiment has a more rigorous construction of its equivalent single-sideband modulation signal, which is applicable to all signal processing methods, and the wide bandwidth of the signal is preserved while noise is removed.

[0075] Furthermore, Fig. 6 is a schematic diagram of the signal after acquisition processing of the present invention. As can be seen from Fig. 6, multiple detection signals with different modulation phases are acquired based on modulation signals with different initial phases, and the detection signals are processed to obtain equivalent single sideband modulation signals, and then the processed signals can be obtained along the demodulation direction.

[0076] Further, please refer to Figures 7 and 8. Figure 7 is a schematic diagram of a processed signal obtained by the single-sideband phase-sensitive detection method of the present invention. Figure 8 is a schematic diagram of a processed signal obtained by the direct sampling method. As can be seen from Figure 7, the single-sideband phase-sensitive detection method of the present invention restores high-frequency and low-frequency signals and preserves the wide bandwidth of the signal. As can be seen from Figure 8, in the processed signal obtained by the direct sampling method, the low-frequency signal is completely masked by the noise signal. As can be seen from Figures 7 and 8, the single-sideband phase-sensitive detection method of the present invention improves the accuracy of the processed signal obtained, which is advantageous for acquiring high-sensitivity wideband signals.

[0077] Further, referring to Fig. 9, as an implementation of the above single-sideband phase-sensitive detection method, the present invention provides an embodiment of a single-sideband phase-sensitive detection system, which corresponds to the method embodiment shown in Fig. 2.

[0078] As shown in FIG. 9 , the single-sideband phase-sensitive detection system 900 of this embodiment may include a timing controller 901, a signal collector 902, and a signal processor 903. Here, the timing controller 901 is used to control the modulating signal or trigger the target signal. The signal collector 902 is used to acquire multiple sets of detection signals with different modulation phases obtained by modulating the target signal repeatedly triggered based on the modulating signal. The signal processor 903 is used to receive the multiple sets of detection signals acquired by the signal collector, post-process the multiple sets of detection signals to obtain multiple sets of equivalent single-sideband modulated signals, and demodulate the multiple sets of equivalent single-sideband modulated signals to obtain processed signals.

[0079] In this embodiment, the specific processing of the timing controller 901, the signal collector 902, and the signal processor 903 in the single-sideband phase-sensitive detection system 900 and the resulting technical effects have been described in the embodiment corresponding to Figure 2, so description thereof will be omitted here.

[0080] In some alternative implementations of this embodiment, the signal collector 902 can acquire a detection signal by collecting a continuous reference signal, determining the frequency of the trigger signal based on the principle of aliasing between the modulating signal and the trigger signal, and repeatedly triggering the target signal in the detection system with the trigger signal to change the modulation phase of the modulating signal at each trigger time. Alternatively, the trigger signal and the modulating signal of the target signal can be time-controlled so that the modulating signal has different modulation phases at multiple trigger times of the trigger signal, and the target signal in the detection system can be repeatedly triggered with the trigger signal. The target signal triggered each time is modulated based on the modulating signal to obtain multiple sets of detection signals with different modulation phases.

[0081] In some alternative implementations of this embodiment, the signal processor 903 may high-pass filter multiple sets of detection signals to obtain multiple sets of filtered signals; perform Hilbert transform on the multiple sets of filtered signals to obtain multiple sets of transformed signals; packetize and superimpose the multiple sets of filtered signals and the multiple sets of transformed signals to obtain multiple sets of equivalent single-sideband modulated signals; depending on the application scenario, if the signal bandwidth is smaller than twice the modulation frequency, perform Hilbert transform on the multiple sets of filtered signals to obtain multiple sets of transformed signals; packetize and superimpose the multiple sets of filtered signals and the multiple sets of transformed signals to obtain multiple sets of equivalent single-sideband modulated signals; or determine the multiple sets of filtered signals as multiple sets of equivalent single-sideband modulated signals; obtain a demodulated signal, single-sideband demodulate the multiple sets of equivalent single-sideband modulated signals based on the demodulated signal to obtain multiple sets of demodulated signals; and superimpose and average the multiple sets of demodulated signals to obtain a processed signal.

[0082] In some alternative implementations of this embodiment, the signal processor 903 can filter and demodulate multiple sets of equivalent single-sideband modulated signals based on the demodulated signal to obtain multiple sets of demodulated signals. Specifically, the demodulated signal is multiplied by each set of equivalent single-sideband modulated signals to obtain multiple sets of first signals, and the multiple sets of first signals are low-pass filtered in the sampling direction to obtain multiple sets of demodulated signals. Depending on the application scenario, if the signal bandwidth is smaller than twice the modulation frequency, the multiple sets of first signals can be low-pass filtered in the sampling direction to obtain multiple sets of demodulated signals, or the multiple sets of first signals can be low-pass filtered in the time axis direction to obtain multiple sets of demodulated signals. Alternatively, the multiple sets of equivalent single-sideband modulated signals can be phase-shift demodulated based on the demodulated signal to obtain multiple sets of demodulated signals. Specifically, the demodulated signals are multiplied by respective sets of equivalent single-sideband modulated signals to obtain multiple sets of second signals, a phase-shift operation is performed on the demodulated signals to obtain phase-shifted demodulated signals, the multiple sets of equivalent single-sideband modulated signals are subjected to a Hilbert transform to obtain multiple sets of third signals, the phase-shifted demodulated signals are multiplied by respective sets of third signals to obtain multiple sets of fourth signals, and the multiple sets of second signals and the multiple sets of fourth signals are superimposed to obtain multiple sets of demodulated signals.

[0083] According to an embodiment of the present invention, the present invention further provides an electronic device, a readable storage medium, and a computer program product.

[0084] FIG. 10 is a schematic block diagram of an electronic device 1000 in which an embodiment of the present invention may be implemented. Electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, servers, blade servers, mainframes, and other suitable computers. Electronic device may also represent signal acquisition devices, such as signal generators, digital-to-analog converters, and other similar devices. The components, their connections and relationships, and their functions shown herein are merely exemplary and are not intended to limit the implementation of the present invention as described and / or claimed herein.

[0085] 10, the equipment 1000 includes a computing unit 1001, which performs various appropriate operations and processes based on a computer program stored in a read-only memory (ROM) 1002 or loaded from a storage unit 1008 into a random access memory (RAM) 1003. The RAM 1003 may further store various programs and data necessary for the operation of the equipment 1000. The computing unit 1001, the ROM 1002, and the RAM 1003 are connected to each other by a bus 1004. An input / output (I / O) interface 1005 is also connected to the bus 1004.

[0086] Several components in the equipment 1000 are connected to an I / O interface 1005, including input units 1006, such as a keyboard, a mouse, a signal collector or a signal receiver, output units 1007, such as various types of monitors, speakers, a storage unit 1008, such as a magnetic disk, an optical disk, and a communication unit 1009, such as a network card. The communication unit 1009 enables the equipment 1000 to exchange information / data with other equipment via computer networks, such as the Internet and / or various telecommunication networks.

[0087] The computing unit 1001 may be a variety of general-purpose and / or special-purpose processing components having processing and computing capabilities. Some examples of the computing unit 1001 include, but are not limited to, a digital signal processor (DSP), any suitable processor, controller, microcontroller, etc. The computing unit 1001 performs the methods and processes described above, such as single-sideband filtering the detected signal to obtain an equivalent single-sideband modulated signal and demodulating the equivalent single-sideband modulated signal to obtain a processed signal. For example, in some embodiments, the methods of single-sideband filtering the detected signal to obtain an equivalent single-sideband modulated signal and demodulating the equivalent single-sideband modulated signal to obtain a processed signal may be implemented as a computer software program tangibly embodied in a machine-readable medium, such as the storage unit 1008. In some embodiments, some or all of the computer program is loaded and / or installed into the facility 1000 via the ROM 1002 and / or the communication unit 1009. When the computer program is loaded into RAM 1003 and executed by the computing unit 1001, it can perform one or more steps of the above-mentioned method, which involves performing single-sideband filtering on the detected signal to obtain an equivalent single-sideband modulated signal, and demodulating the equivalent single-sideband modulated signal to obtain a processed signal.

[0088] Embodiments of the systems and techniques described herein may be realized in digital electronic circuitry, integrated circuit systems, application specific integrated circuits (ASICs), computer hardware, firmware, software, and / or combinations thereof. These embodiments may be embodied in one or more computer programs that may be executed and / or interpreted by a programmable system including at least one programmable processor. The programmable processor, which may be a special-purpose or general-purpose programmable processor, may receive data and instructions from, and transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0089] The program code for implementing the methods of the present invention may be written in any combination of one or more programming languages. These program codes are supplied to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, and when executed by the processor or controller, perform the functions / operations specified in the flowcharts and / or block diagrams. The program code may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a separate software package, or entirely on a remote machine or server.

[0090] In this specification, a machine-readable medium may be a tangible medium that can contain or store a program for use by or in combination with an instruction execution system, device, or facility. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. More specific examples of machine-readable storage media include one or more wire-based electrical connections, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), or any suitable combination of the above.

[0091] The systems and techniques described herein can be implemented on a computer to provide interaction with a user. The computer may include a display device for displaying the table to the user, a keyboard, and a pointing device (e.g., a mouse). The user can provide input to the computer via the keyboard and pointing device.

[0092] A computer system may include clients and servers. Clients and servers are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on corresponding computers and having a client-server relationship to each other.

[0093] It should be understood that various forms of the above processes, rearrangements, additions, or deletions of steps can be used, for example, the steps described in this disclosure can be performed in parallel or in a different order, and this specification is not limited thereto, as long as the technical solution of the present disclosure can achieve the desired results.

[0094] The above specific embodiments do not limit the scope of protection of the present disclosure. It is obvious that a person skilled in the art of the present disclosure can think of various modifications or alterations within the scope of the technical idea described in the claims. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present disclosure should be included in the scope of protection of the present disclosure.

Claims

1. 1. A single-sideband phase-sensitive detection method, comprising: repeatedly triggering a target signal in a detection system and varying the modulation phase of the modulated signal at each trigger time; modulating the target signal triggered each time based on the modulated signal to obtain a plurality of sets of detection signals with different modulation phases; post-processing the sets of detected signals to obtain sets of equivalent single-sideband modulated signals; demodulating the plurality of sets of equivalent single sideband modulated signals to obtain processed signals; A method comprising:

2. The step of repeatedly triggering a target signal in a detection system and varying a modulation phase of a modulated signal at each trigger time includes: acquiring a continuous modulated signal; determining a frequency of the trigger signal based on an aliasing principle between the modulating signal and a trigger signal; a step of repeatedly triggering a target signal in the detection system by the trigger signal to change a modulation phase of the modulated signal at each trigger time; The method of claim 1 , comprising:

3. The step of repeatedly triggering a target signal in a detection system and varying a modulation phase of a modulated signal at each trigger time includes: timing the trigger signal and the modulating signal of the target signal such that the modulating signal has different modulation phases at multiple trigger times of the trigger signal; repeatedly triggering the target signal in the detection system with the trigger signal; The method of claim 1 , comprising:

4. The step of post-processing the plurality of sets of detected signals to obtain a plurality of sets of equivalent single-sideband modulated signals comprises: high-pass filtering the plurality of sets of detected signals to obtain a plurality of sets of filtered signals; performing a Hilbert transform on the plurality of sets of filtered signals to obtain a plurality of sets of transformed signals, and packetizing and superimposing the plurality of sets of filtered signals and the plurality of sets of transformed signals to obtain the plurality of sets of equivalent single sideband modulated signals; The method of claim 1 , comprising:

5. The step of post-processing the plurality of sets of detected signals to obtain a plurality of sets of equivalent single-sideband modulated signals comprises:

5. The method of claim 4, further comprising the step of determining the sets of filtered signals as the sets of equivalent single-sideband modulated signals if the signal bandwidth is less than twice the modulation frequency.

6. The step of demodulating the plurality of sets of equivalent single sideband modulated signals to obtain a processed signal comprises: obtaining a demodulated signal; performing single-sideband demodulation on the plurality of sets of equivalent single-sideband modulated signals based on the demodulated signals to obtain a plurality of sets of demodulated signals; superimposing and averaging the plurality of sets of demodulated signals to obtain the processed signal; The method of claim 5 , comprising:

7. The step of single-sideband demodulating the plurality of sets of equivalent single-sideband modulated signals based on the demodulated signals to obtain a plurality of sets of demodulated signals includes: filter-demodulating the plurality of sets of equivalent single-sideband modulated signals based on the demodulated signals to obtain the plurality of sets of demodulated signals; or 7. The method of claim 6, further comprising the step of phase-shift demodulating the plurality of sets of equivalent single-sideband modulated signals based on the demodulated signals to obtain the plurality of sets of demodulated signals.

8. The step of filter-demodulating the plurality of sets of equivalent single-sideband modulated signals based on the demodulated signals to obtain the plurality of sets of demodulated signals includes: multiplying the demodulated signals with respective sets of equivalent single sideband modulated signals to obtain a plurality of sets of first signals; performing low-pass filtering in a sampling direction on the plurality of sets of first signals to obtain the plurality of sets of demodulated signals; The method of claim 7, comprising:

9. The step of filter-demodulating the plurality of sets of equivalent single-sideband modulated signals based on the demodulated signals to obtain the plurality of sets of demodulated signals includes:

9. The method of claim 8, further comprising: when a signal band is less than twice the modulation frequency, performing low-pass filtering on the sets of first signals in a time axis direction to obtain the sets of demodulated signals.

10. the step of phase-shift demodulating the plurality of sets of equivalent single-sideband modulated signals based on the demodulated signals to obtain the plurality of sets of demodulated signals, multiplying the demodulated signals with respective sets of equivalent single sideband modulated signals to obtain a plurality of sets of second signals; a step of phase-shifting the demodulated signal to obtain a phase-shifted demodulated signal; performing a Hilbert transform on the plurality of sets of equivalent single sideband modulated signals to obtain a plurality of sets of third signals; multiplying the phase-shifted demodulated signals by respective sets of third signals to obtain a plurality of sets of fourth signals; superimposing the plurality of sets of second signals and the plurality of sets of fourth signals to obtain the plurality of sets of demodulated signals; The method of claim 7, comprising:

11. 1. A single-sideband phase-sensitive detection system comprising: a timing controller used to control the modulating signal or trigger the target signal; a signal collector for acquiring a plurality of sets of detection signals having different modulation phases obtained by modulating the target signal repeatedly triggered by the modulating signal; a signal processor for receiving a plurality of sets of detection signals acquired by the signal collector, post-processing the plurality of sets of detection signals to obtain a plurality of sets of equivalent single sideband modulated signals, and demodulating the plurality of sets of equivalent single sideband modulated signals to obtain processed signals; Including, the system.

12. at least one processor; a memory communicatively coupled to the at least one processor; Including, 11. An electronic device, wherein the memory stores instructions executable by the at least one processor, the instructions being executable by the at least one processor to cause the at least one processor to perform the method of any one of claims 1 to 10.

13. 11. A non-transitory computer readable storage medium having stored thereon computer instructions for causing the computer to perform the method of any one of claims 1 to 10.

14. A computer program product comprising a computer program, A computer program product, the computer program being executed by a processor to implement the method of any one of claims 1 to 10.

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