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 of related applications This application claims priority to China Patent Application No. 202211082749.6 (Title of Invention: Signal Detection Method and System), filed on 6 September 2022, all of which are incorporated herein by reference. The present invention relates to signal processing and signal amplification technologies, and can be applied to situations such as signal detection. In particular, it relates to a single-sideband phase-sensitive detection method, system, equipment, storage medium, and computer program product. [Background technology]

[0002] In scientific research, processing weak signals is extremely important. For example, detecting magnetic resonance signals, infrared signals, and radar signals are all examples of weak signals that people are concerned about.

[0003] A lock-in amplifier is an amplifier that performs phase-sensitive detection of weak signals. It is an effective method for detecting weak signals by significantly suppressing interference noise and improving the signal-to-noise ratio of the signal. The signal frequency that a lock-in amplifier typically detects is much lower than the modulation frequency of the lock-in amplifier. Conventional lock-in amplification techniques cannot solve the problem when the detected signal includes a variable signal and subsequent evolution over a wide time domain, especially when the changing signal bandwidth is higher than the modulation frequency. Therefore, high-sensitivity signal detection over a wide time domain is extremely difficult. [Overview of the project]

[0004] The present invention improves the detection sensitivity of weak, broadband signals by providing a single-sideband phase-sensitive detection method (SSB-PSD), system, equipment, storage medium, and computer program product.

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

[0006] According to another aspect of the present invention, a single-sideband phase-sensitive detection system is provided, comprising: a timing controller used for controlling a modulated signal or triggering a target signal; a signal extractor for acquiring multiple sets of detection signals having different modulation phases obtained by modulating a target signal repeatedly triggered by the modulated signal; and a signal processor for receiving the multiple sets of detection signals acquired by the signal extractor, 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 a processed signal.

[0007] According to another aspect of the present invention, an electronic device is provided that includes at least one processor and a memory communicated to the at least one processor, wherein the memory contains instructions that can be executed by the at least one processor. When the instructions are executed by the at least one processor, the at least one processor can perform the single-sideband phase-sensitive detection method.

[0008] According to another aspect of the present invention, a non-temporary computer-readable storage medium is provided which stores computer instructions. The computer instructions are for the computer to execute the single-sideband phase-sensitive detection method.

[0009] According to another aspect of the present invention, a computer program product is applied which includes a computer program, and when the computer program is executed by a processor, the single-sideband phase-sensitive detection method is realized.

[0010] Furthermore, the contents described herein are not intended to represent key or important features of the embodiments of the present invention, nor do they limit the scope of the invention. Other features of the present invention will be readily apparent from the following description. [Brief explanation of the drawing]

[0011] The drawings are for the purpose of further understanding the present invention and do not limit it. [Figure 1] This is an exemplary system architecture diagram to which the present invention can be applied. [Figure 2] This is a flowchart of one embodiment of the single-sideband phase-sensitive detection method of the present invention. [Figure 3] This is a flowchart of another embodiment of the single-sideband phase-sensitive detection method of the present invention. [Figure 4] This is a schematic diagram of phase control for the detection signal according to the present invention. [Figure 5] This is a schematic diagram of the signal spectrum of the single-sideband phase-sensitive detection method of the present invention. [Figure 6] A schematic diagram of the signal after the acquisition process of the present invention. [Figure 7] A schematic diagram of the processed signal obtained by the single-sideband phase-sensitive detection method of the present invention. [Figure 8] This is a schematic diagram of the processed signal obtained by the direct sampling method. [Figure 9] This is a schematic diagram of the structure of one embodiment of the single-sideband phase-sensitive detection system of the present invention. [Figure 10] This is a block diagram of the electronic equipment for realizing the single-sideband phase-sensitive detection method according to an embodiment of the present invention. [Modes for carrying out 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 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 brevity, descriptions of well-known functions and configurations are omitted in the following description.

[0013] FIG. 1 shows an exemplary system architecture 100 that can use an embodiment of the unilateral band phase-sensitive detection method of the present invention.

[0014] As shown in FIG. 1, the system architecture 100 may include terminal devices 101 and 102, a network 103, and a server 104. The network 103 is a medium for providing a communication link between the terminal devices 101 and 102 and the server 104. The network 103 may include various connection types such as wired, wireless communication links, or optical fiber cables.

[0015] The user can obtain detection signals and the like by interacting with the server 104 via the network 103 using the terminal devices 101 and 102. The terminal devices 101 and 102 perform timing control and analog signal control, and then convert the analog signal into a digital signal via a digital-to-analog converter, and can be further used to correspond to the server 104 via the network 103.

[0016] The terminal equipment 101 and 102 may be hardware or software. If hardware, terminal equipment 101 and 102 may be various signal acquisition equipment, timing control equipment, electronic equipment, including but not limited to photoelectric signal sensors, laptop computers, and desktop computers. If software, terminal equipment 101 and 102 may be installed on the above-mentioned electronic equipment and may be implemented as multiple software or software modules, or as a single software or software module, but are not limited thereto.

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

[0018] 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 or software modules (for example, providing a distributed service), or as a single software or software module, but is not limited thereto.

[0019] To ensure clarity, the number of terminals, networks, and servers shown in Figure 1 are illustrative only. Any number of terminals, networks, and servers can be used as needed.

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

[0021] Step 201: The target signal in the system under detection is repeatedly triggered, changing the modulation phase of the modulated signal at each trigger time.

[0022] In this embodiment, the implementer of the single-sideband phase-sensitive detection method can repeatedly trigger a target signal in the system under detection and change the modulation phase of the modulated signal at each trigger time. Here, the target signal in the system under detection can be generated repeatedly. In some specific physical systems, the target signal is so weak that it cannot be directly detected, and therefore it is necessary to modulate it based on the modulated signal in order to acquire the target signal. The target signal can be modulated multiple times based on the modulated signal. Specifically, the timing at which the target signal is generated can be controlled so that the target signal is generated repeatedly at multiple trigger times and 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 entire cycle.

[0023] Step 202: The target signal, which is triggered each time based on the modulated signal, is modulated to obtain multiple sets of detection signals with different modulation phases.

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

[0025] Step 203: Post-process multiple sets of detection signals to obtain multiple sets of equivalent single-sideband modulated signals. In this embodiment, the implementing entity can obtain multiple sets of detection signals and then post-process them to obtain multiple sets of equivalent single-sideband modulated signals. Specifically, 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 the frequency threshold, all signals below the frequency threshold in each set of detection signals are cut, and signals above the frequency threshold are retained to obtain multiple sets of filtered signals, and these filtered signals are determined to be multiple sets of equivalent single-sideband modulated signals.

[0026] The obtained detection signal contains various noise signals. The distribution of 1 / f noise, which is widely present in nature, shows that noise intensity increases with lower frequency. Therefore, in order to accurately detect the target signal, it is necessary to remove noise signals in the detection signal, especially low-frequency noise signals. Because the target signal's frequency is shifted to near the modulation frequency during modulation processing, it contains both lower and upper sideband signals. By suppressing the lower sideband signal and retaining the upper sideband signal in the detection signal, noise can be removed while maintaining a wide bandwidth.

[0027] Step 204: Demodulate multiple equivalent single-sideband modulated signals to obtain the processed signal.

[0028] In this embodiment, the implementing entity can obtain a processed signal by acquiring multiple sets of equivalent single-sideband modulated signals and then demodulating them. Specifically, it acquires a demodulated signal, demodulates multiple sets of equivalent single-sideband modulated signals based on the demodulated signal, and uses the demodulated signal as the processed signal. The demodulated signal may be acquired before executing step 201, or after executing at least one of the steps in steps 201-203, and this invention is not limited thereto. The demodulated signal may be acquired using signal acquisition equipment, or the frequency and phase of the modulated signal may be acquired and the signal generated by simulation may be used as the demodulated signal, and this invention is not limited thereto. Here, the demodulated signal and the modulated signal have the same frequency and phase.

[0029] In the single-sideband phase-sensitive detection method provided in an embodiment of the present invention, first, a target signal in the system to be detected is repeatedly triggered, changing the modulation phase of the modulated signal at each trigger time. Then, the target signal that was triggered each time is modulated based on the modulated signal to obtain multiple sets of detection signals having 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 the processed signal. By removing noise through single-sideband filtering, most of the low-frequency noise in the detection signal is removed, thus improving the accuracy of the processed signal. In addition, because the wide bandwidth in the detection signal is preserved by single-sideband filtering, the mutation signal in the detection signal is not distorted or deformed. 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] Furthermore, Figure 3 is a flowchart 300 of another embodiment of the single-sideband phase-sensitive detection method according to the present invention. This single-sideband phase-sensitive detection method includes the following steps.

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

[0032] In this embodiment, the specific operation of step 301 was explained in detail in step 201 of the embodiment shown in Figure 2, so the explanation is omitted here.

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

[0034] Specifically, Figure 4 is a schematic diagram of the phase control of the 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 system to be detected can be repeatedly generated based on the frequency of the trigger signal. The generated target signals are overlapping but do not overlap each other. Based on the aliasing principle between the modulated signal and the trigger signal, the generation frequency of the trigger signal can be determined, 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 multiple trigger times. This allows for the control of repeated generation of the target signal at multiple different trigger times under a continuous modulated signal, and multiple sets of detection signals can be obtained by modulating the target signals repeatedly generated based on this continuous modulated signal. Since the modulated signal has a different modulation phase at each trigger time, the multiple sets of detection signals obtained also have different initial phases.

[0035] In some feasible forms of this embodiment, the timing of the trigger signal and the modulation signal of the target signal can be controlled so that the modulation signal has different modulation phases at multiple trigger times of the trigger signal. The trigger signal repeatedly triggers the target signal in the system under detection.

[0036] Specifically, referring to Figure 4, as can be seen from Figure 4(b), by controlling the timing of the trigger signal and modulation signal of the target signal to generate multiple sets of modulation signals, each time a trigger signal occurs, the multiple sets of modulation signals will have different modulation phases at each trigger time, and the generated multiple sets of modulation signals can be controlled to generate multiple modulation phases at many trigger times. As a result, at each trigger time, based on the corresponding set of modulation signals, the target signal generated at this trigger time can be modulated to obtain one set of detection signals. This results in the acquisition of multiple sets of detection signals. Since each set of modulation signals has a different modulation phase, the obtained multiple sets of detection signals also have different initial phases.

[0037] Step 302: Modulate the triggered target signal based on the modulated signal to obtain multiple sets of detection signals with different modulation phases.

[0038] In this embodiment, the specific operation of step 302 has been explained in detail in step 202 in the embodiment shown in Figure 2 and step 301 in the embodiment shown in Figure 3, so the explanation is omitted here.

[0039] Note that the obtained set of multiple detection signals consists of at least two sets of detection signals. When there are multiple sets of detection signals, each detection signal has a corresponding other detection signal with a modulation phase shifted by π / 2. If there are only two sets of detection signals, the phase difference of the modulation signals at the initial point of the two sets of detection signals is π / 2.

[0040] Step 303: High-pass filtering is performed on multiple sets of detection signals to obtain multiple sets of filtered signals.

[0041] In this embodiment, the specific operation of step 303 was explained in detail in step 203 of the embodiment shown in Figure 2, so the explanation is omitted here.

[0042] Step 304: Perform a Hilbert transform on multiple filtered signals to obtain multiple converted signals. Packetize the multiple filtered signals and the multiple converted signals and superimpose them to obtain multiple equivalent single-sideband modulated signals.

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

number

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

number

[0045] Each modulated signal is also a periodically changing signal, and modulated signals can be expressed in the form of the following cosine signal.

number

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

Equation

[0047] When the modulation frequency is ω mod , the initial modulation phase sampled at the k-th time in the sampling direction is φ mod (k), b is the linear modulation amplitude, and a single-sideband modulation signal can be obtained. The single-sideband modulation signal can be expressed by the following formula.

Equation

[0048] When F(t,k) is expanded, its real part signal can be expressed as follows.

Equation

Equation

[0049] The signal may be mixed with noise during the transmission process. Due to the influence of noise, the detected signal also contains a noise signal. The signal actually detected after modulation may also contain a noise signal, specifically, it is expressed by the following formula.

Equation

number

[0050] Multiple sets of filtered signals are subjected to a Hilbert transform to obtain multiple sets of transformed signals. Here, a Hilbert transform refers to performing a Hilbert operation on the filtered signals. This operation is used to construct the following portion of the equivalent single-sideband modulated signal.

number

[0051] Select a signal from a different sampling batch from multiple filtered signals and shift its phase by π / 2 compared to the modulation signal corresponding to the converted signal. That is, the modulation phase of the filtered signal is φ mod (k') is the converted signal modulation phase φ mod (k) has the following relationship:

number

[0052] This operation is intended to construct the following portion of the equivalent single-sideband modulated signal.

number

[0053] Multiple equivalent single-sideband modulated signals can be obtained by superimposing the filtered signals with a phase difference of π / 2 onto the converted signals. The format is as follows:

number

[0054] Figure 5 is a schematic diagram of the signal spectrum related to the single-sideband phase-sensitive detection method of the present invention. The target signal is shown in Figure 5(a). In some specific physical systems, the target signal is so weak that it cannot be detected directly; therefore, the target signal can only be obtained after it has been modulated based on the modulated signal. The detected signal is shown in Figure 5(b). By repeatedly triggering the target signal in the system to be detected, changing the modulation phase at each trigger time of the modulated signal, and modulating the target signal that has been triggered each time based on the modulated signal, multiple sets of detection signals with different modulation phases can be obtained. As can be seen from Figure 5(b), when the signal bandwidth is greater than twice the modulation frequency, an image signal is generated in the detection signal. The equivalent single-sideband modulated signal is shown in Figure 5(c). When the signal bandwidth is greater than twice the modulation frequency, an image signal is generated in the detection signal, so multiple sets of detection signals are high-pass filtered. The filtered signal cannot be determined as an equivalent single-sideband modulated signal. Multiple filtered signals are subjected to a Hilbert transform to obtain multiple converted signals. These multiple filtered signals and the multiple converted signals are then packetized and superimposed to obtain multiple equivalent single-sideband modulated signals, thereby obtaining a precisely equivalent single-sideband modulated signal. Figure 5(d) shows the demodulated signal. After obtaining the equivalent single-sideband modulated signal, the multiple equivalent single-sideband modulated signals are demodulated in a single-sideband manner based on the demodulated signal to obtain a more accurately demodulated signal.

[0055] Alternatively, multiple sets of detection signals may be high-pass filtered to obtain multiple sets of filtered signals, then the filtered signals may be Hilbert transformed to obtain multiple sets of transformed signals, and then the filtered signals and the transformed signals may be packetized and superimposed to obtain multiple sets of equivalent single-sideband modulated signals. Alternatively, multiple sets of detection signals may be Hilbert transformed to obtain multiple sets of transformed signals, the detected signals and the transformed signals may be packetized and superimposed, and then the superimposed signal may be high-pass filtered to obtain multiple sets of equivalent single-sideband modulated signals. The present invention is not limited to these methods.

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

[0057] Specifically, in application scenarios where the signal bandwidth is less than twice the modulation frequency, the implementing entity can obtain multiple sets of filtered signals, then perform a Hilbert transform on these multiple sets of filtered signals to obtain multiple sets of converted signals, packetize the multiple sets of filtered signals and the multiple sets of converted signals and superimpose them to obtain multiple sets of equivalent single-sideband modulated signals, or it can determine the multiple sets of filtered signals directly as multiple sets of equivalent single-sideband modulated signals.

[0058] Step 305: Obtain the demodulated signal.

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

[0060] Step 306: Based on the demodulated signal, multiple sets of equivalent single-sideband modulated signals are demodulated in a single-sideband manner to obtain multiple sets of demodulated signals.

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

[0062] In several selectable implementations of this embodiment, multiple sets of demodulated signals can be obtained by filter demodulating multiple sets of equivalent single-sideband modulated signals based on the demodulated signal. Specifically, multiple sets of first signals are obtained by multiplying each demodulated signal by the equivalent single-sideband modulated signal, and multiple sets of demodulated signals are obtained by performing low-pass filtering in the sampling direction on the multiple sets of first signals.

[0063] Specifically, each pair of equivalent single-sideband modulated signals can be multiplied with a demodulated signal having the same initial phase as the equivalent single-sideband modulated signal. Here, multiple pairs of equivalent single-sideband modulated signals have different initial phases. Low-pass filtering is performed on the multiplied signal in the sampling direction; that is, multiple pairs of multiplied signals with different initial phases are low-pass filtered at the same time and with different sampling counts. By using a filtering method in the sampling direction instead of a conventional filtering method on the time axis, a signal with high temporal resolution can be obtained.

[0064] The equivalent single-sideband modulation signal of the k-th set in the sampling direction is expressed by the following equation.

number

[0065] The demodulated signal can be multiplied by each set of equivalent single-sideband modulated signals. The first signal of the k-th set obtained is expressed by the following equation.

number

[0066]

number

number

[0067] In some of the selectable implementations of this embodiment, the implementing entity may, after obtaining multiple sets of first signals, perform low-pass filtering in the time axis direction on the multiple sets of first signals, depending on whether the signal bandwidth is less than twice the modulation frequency, to obtain multiple sets of demodulated signals.

[0068] Specifically, in application scenarios where the signal bandwidth is smaller than twice the modulation frequency, the implementing entity may, after obtaining multiple sets of first signals, perform low-pass filtering in the sampling direction on the multiple sets of first signals to obtain multiple sets of demodulated signals, or multiply each demodulated signal by the equivalent single-sideband modulated signal of each set, and perform low-pass filtering in the time axis direction on the multiple sets of multiplied signals to obtain multiple sets of demodulated signals. Here, low-pass filtering can be performed on the multiple sets of multiplied signals using any digital filter or hardware filter.

[0069] In some selectable implementations of this embodiment, multiple sets of demodulated signals can be obtained by phase-shift demodulating multiple sets of equivalent single-sideband modulated signals based on the demodulated signal. Specifically, multiple sets of second signals can be obtained by multiplying each demodulated signal by the equivalent single-sideband modulated signal, a phase-shift operation can be performed on the demodulated signal to obtain a phase-shift demodulated signal, multiple sets of third signals can be obtained by performing a Hilbert transform on the multiple sets of equivalent single-sideband modulated signals, multiple sets of fourth signals can be obtained by multiplying each phase-shift demodulated signal by the third signal, and multiple sets of second signals can be superimposed on the multiple sets of fourth signals to obtain multiple demodulated signals.

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

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

[0072] In this embodiment, the implementing entity can obtain multiple sets of demodulated signals, superimpose these multiple sets of demodulated signals to obtain a superimposed signal, and then average the superimposed signal to obtain the processed signal. By superimposing multiple sets of demodulated signals, noise can be effectively removed as the amount of data increases, and the signal-to-noise ratio of the processed signal can be improved.

[0073] After demodulating an equivalent single-sideband modulated signal, two signals are obtained. The real part is the I-channel signal, and the imaginary part is the Q-channel signal. After processing using the method described above, 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 to the embodiment corresponding to Figure 2, the single-sideband phase-sensitive detection method in this embodiment constructs its equivalent single-sideband modulated signal more precisely and is applicable to all signal processing methods. The wide bandwidth of the signal is preserved while noise is removed.

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

[0076] Furthermore, 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 while maintaining the broad 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 obtained processed signal and is advantageous for acquiring highly sensitive, broadband signals.

[0077] Furthermore, refer to Figure 9. As an implementation of the above-described single-sideband phase-sensitive detection method, the present invention provides an embodiment of a single-sideband phase-sensitive detection system. This embodiment of the system corresponds to the method embodiment shown in Figure 2.

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

[0079] In this embodiment, the specific processing of the timing controller 901, signal extractor 902, and signal processor 903 in the single-sideband phase-sensitive detection system 900, and the resulting technical effects, have been explained in the embodiment corresponding to Figure 2, and therefore will not be explained here.

[0080] In several selectable implementations of this embodiment, the signal extractor 902 can acquire a detection signal. A continuous reference signal is acquired, the frequency of the trigger signal is determined based on the aliasing principle between the modulated signal and the trigger signal, and the modulation phase of the modulated signal is changed at each trigger time by repeatedly triggering the target signal in the system under detection with the trigger signal. Alternatively, the timing of the trigger signal and the modulated signal of the target signal is controlled so that the modulated signal has different modulation phases at multiple trigger times of the trigger signal, and the target signal in the system under detection is repeatedly triggered with the trigger signal. The target signal, which is triggered each time based on the modulated signal, is modulated to obtain a detection signal having multiple sets of different modulation phases.

[0081] In some selectable implementations of this embodiment, the signal processor 903 can obtain multiple filtered signals by high-pass filtering multiple sets of detection signals. Multiple filtered signals can be Hilbert transformed to obtain multiple transformed signals, and the multiple filtered signals and the multiple transformed signals can be packetized and superimposed to obtain multiple equivalent single-sideband modulated signals. Depending on the application, if the signal bandwidth is smaller than twice the modulation frequency, multiple filtered signals can be Hilbert transformed to obtain multiple transformed signals, and the multiple filtered signals and the multiple transformed signals can be packetized and superimposed to obtain multiple equivalent single-sideband modulated signals, or multiple filtered signals can be determined as multiple equivalent single-sideband modulated signals. A demodulated signal is obtained, and based on the demodulated signal, multiple equivalent single-sideband modulated signals are single-sideband demodulated, multiple demodulated signals are obtained, and the multiple demodulated signals are superimposed and averaged to obtain a processed signal.

[0082] In some selectable 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 low-pass filtering in the sampling direction is performed on the multiple sets of first signals to obtain multiple sets of demodulated signals. Depending on the application, if the signal bandwidth is smaller than twice the modulation frequency, low-pass filtering in the sampling direction may be performed on the multiple sets of first signals to obtain multiple sets of demodulated signals, or low-pass filtering in the time axis direction may be performed on the multiple sets of first signals to obtain multiple sets of demodulated signals. Alternatively, multiple sets of demodulated signals can be obtained by phase-shift demodulating multiple sets of equivalent single-sideband modulated signals based on the demodulated signal. Specifically, the demodulated signal is multiplied by each set of equivalent single-sideband modulated signals to obtain multiple sets of second signals, a phase shift operation is performed on the demodulated signal to obtain a phase-shifted demodulated signal, multiple sets of third signals are obtained by performing a Hilbert transform on the multiple sets of equivalent single-sideband modulated signals, multiple sets of fourth signals are obtained by multiplying each set of third signals by each set of phase-shifted demodulated signals, and multiple sets of demodulated signals are obtained by superimposing the multiple sets of second signals and the multiple sets of fourth signals.

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

[0084] Figure 10 is an implementable schematic block diagram of an electronic installation 1000 of an embodiment of the present invention. The electronic installation is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, servers, blade servers, mainframe computers, and other suitable computers. The electronic installation may also represent signal acquisition equipment, such as signal generators, digital-to-analog converters, and other similar equipment. The components shown herein, their connections and relationships, and their functions are illustrative and are not intended to limit the implementation of the present invention as described and / or required herein.

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

[0086] Multiple components in the equipment 1000 are connected to the I / O interface 1005 and include, for example, input units 1006 such as a keyboard, mouse, signal collector or signal receiver; output units 1007 such as various types of monitors and speakers; storage units 1008 such as magnetic disks and optical disks; and communication units 1009 such as a network card. The communication units 1009 enable the equipment 1000 to exchange information / data with other equipment via computer networks such as the Internet and / or various telecommunications networks.

[0087] The computing unit 1001 may be a variety of general-purpose and / or dedicated 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 each of the above methods and processes, for example, by single-sideband filtering the detection signal to obtain an equivalent single-sideband modulated signal, and by demodulating the equivalent single-sideband modulated signal to obtain a processed signal. For example, in some embodiments, the method of performing single-sideband filtering on the detection signal to obtain an equivalent single-sideband modulated signal, and demodulating the equivalent single-sideband modulated signal to obtain a processed signal can be implemented as a computer software program specifically embodied in a machine-readable medium such as a storage unit 1008. In some embodiments, part or all of the computer program is loaded and / or installed into the equipment 1000 by ROM 1002 and / or communication unit 1009. When a computer program is loaded into RAM 1003 and executed by the computing unit 1001, one or more of the above steps can be performed, which involve performing single-sideband filtering on the detection signal to obtain an equivalent single-sideband modulated signal, and demodulating the equivalent single-sideband modulated signal to obtain the processed signal.

[0088] Each embodiment of the systems and technologies described herein can be implemented by digital electronic circuit systems, integrated circuit systems, application-specific integrated circuits (ASICs), computer hardware, firmware, software, and / or combinations thereof. These embodiments are implemented in one or more computer programs. This one or more computer programs can be executed and / or interpreted on a programmable system including at least one programmable processor. This programmable processor may be a dedicated or general-purpose programmable processor and can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to this storage system, at least one input device, and at least one output device.

[0089] The program code for carrying out the method 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, a dedicated computer, or another programmable data processing device, and when executed by the processor or controller, the functions / operations defined in the flowchart and / or block diagram are performed. 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 an independent software package, or entirely on a remote machine or server.

[0090] In this specification, a machine-readable medium may be a tangible medium containing or capable of storing a program for use by an instruction execution system, device, or equipment, or for use in combination with such an instruction execution system, device, or equipment. A 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, portable computer disks, hard disks, random-access memory (RAM), read-only memory (ROM), or any suitable combination of the above.

[0091] To provide user interaction, a computer may implement the systems and technologies described herein. This computer may include a display device for showing the above table to the user, a keyboard, and a pointing device (e.g., a mouse). The user can input and provide information to the computer via the keyboard and pointing device.

[0092] A computer system may include a client and a server. Clients and servers are generally separate from each other and typically interact via a communication network. The client-server relationship arises from computer programs running on corresponding computers that have a client-server relationship with each other.

[0093] It should be understood that various forms of processes, rearrangements, additions, or deletions can be used as described above. For example, each step described herein may be performed in parallel or in a different order, as long as the technical proposal of this disclosure can achieve the desired result.

[0094] The specific embodiments described above do not limit the scope of protection of this disclosure. It is clear that a person with ordinary skill in the art of this disclosure may conceive of various modifications or alterations within the scope of the technical idea set forth in the claims. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should all be included within the scope of protection of this disclosure.

Claims

1. A single-sideband phase-sensitive detection method, The steps include repeatedly triggering the target signal in the system under detection and changing the modulation phase of the modulated signal at each trigger time, The steps include: modulating the target signal, which is triggered each time based on the modulated signal, to obtain multiple sets of detection signals with different modulation phases; The steps include: post-processing multiple sets of detection signals to obtain multiple sets of equivalent single-sideband modulated signals; The steps include demodulating the multiple sets of equivalent single-sideband modulated signals to obtain a processed signal, Methods that include...

2. The step of repeatedly triggering the target signal in the system under detection and changing the modulation phase of the modulated signal at each trigger time is: The steps include: acquiring a continuous modulated signal, The steps include determining the frequency of the trigger signal based on the aliasing principle between the modulated signal and the trigger signal, The steps include repeatedly triggering the target signal in the system under detection using the trigger signal to change the modulation phase of the modulated signal at each trigger time, The method according to claim 1, including the method described in claim 1.

3. The step of repeatedly triggering the target signal in the system under detection and changing the modulation phase of the modulated signal at each trigger time is: The steps include timing control of the trigger signal and the modulated signal of the target signal such that the modulated signal has different modulation phases at multiple trigger times of the trigger signal, The steps include repeatedly triggering the target signal in the system under detection using the trigger signal, The method according to claim 1, including the method described in claim 1.

4. The step of post-processing multiple sets of detection signals to obtain multiple sets of equivalent single-sideband modulated signals is: The steps include: high-pass filtering of the multiple sets of detection signals to obtain multiple sets of filtered signals; The steps include: obtaining multiple sets of converted signals by performing a Hilbert transform on the multiple sets of filtered signals; packetizing the multiple sets of filtered signals and the multiple sets of converted signals and superimposing them to obtain the multiple sets of equivalent single-sideband modulated signals; The method according to claim 1, including the method described in claim 1.

5. The step of post-processing multiple sets of detection signals to obtain multiple sets of equivalent single-sideband modulated signals is: The method according to claim 4, further comprising the step of determining the plurality of filtered signals as the plurality of equivalent single-sideband modulated signals when the signal bandwidth is less than twice the modulation frequency.

6. The step of demodulating the multiple sets of equivalent single-sideband modulated signals to obtain the processed signal is: Steps to acquire the demodulated signal, The steps include: obtaining multiple sets of demodulated signals by demodulating the multiple sets of equivalent single-sideband modulated signals based on the demodulated signal; The steps include: superimposing and averaging the multiple sets of demodulated signals to obtain the processed signal; The method according to claim 5, including the method described in claim 5.

7. The step of obtaining multiple sets of demodulated signals by demodulating the multiple sets of equivalent single-sideband modulated signals based on the demodulated signal is as follows: Based on the demodulated signal, the multiple sets of equivalent single-sideband modulated signals are filter-demodulated to obtain the multiple sets of demodulated signals, or The method according to claim 6, further comprising the step of phase-shifting and demodulating the plurality of equivalent single-sideband modulated signals based on the demodulated signal to obtain the plurality of demodulated signals.

8. The step of obtaining the multiple sets of demodulated signals by filter demodulating the multiple sets of equivalent single-sideband modulated signals based on the demodulated signal is as follows: The steps include multiplying the demodulated signals by each pair of equivalent single-sideband modulated signals to obtain multiple pairs of first signals, The steps include performing low-pass filtering in the sampling direction on the multiple sets of first signals to obtain the multiple sets of demodulated signals, The method according to claim 7, including the method described in claim 7.

9. The step of obtaining the multiple sets of demodulated signals by filter demodulating the multiple sets of equivalent single-sideband modulated signals based on the demodulated signal is as follows: The method according to claim 8, further comprising the step of performing low-pass filtering in the time axis direction on the plurality of sets of first signals if the signal bandwidth is less than twice the modulation frequency, in order to obtain the plurality of sets of demodulated signals.

10. The step of obtaining the multiple sets of demodulated signals by shifting and demodulating the multiple sets of equivalent single-sideband modulated signals based on the demodulated signal is: The steps include multiplying the demodulated signals by each pair of equivalent single-sideband modulated signals to obtain multiple pairs of second signals, The steps include: obtaining a phase-shifted demodulated signal by shifting the phase of the demodulated signal; The steps include: obtaining multiple sets of third signals by performing a Hilbert transform on the multiple sets of equivalent single-sideband modulated signals; The steps include multiplying the phase-shifted demodulated signals by each set of third signals to obtain multiple sets of fourth signals, The steps include superimposing the multiple sets of second signals and the multiple sets of fourth signals to obtain the multiple sets of demodulated signals, The method according to claim 7, including the method described in claim 7.

11. A single-sideband phase-sensitive detection system, A timing controller used to control a modulated signal or trigger a target signal, A signal extractor for acquiring multiple sets of detection signals having different modulation phases, obtained by modulating the target signal that is repeatedly triggered by the modulated signal, A signal processor for receiving multiple sets of detection signals acquired by the signal extractor, post-processing the multiple sets of detection signals to acquire multiple sets of equivalent single-sideband modulated signals, and demodulating the multiple sets of equivalent single-sideband modulated signals to obtain the processed signal, A system that includes this.

12. At least one processor, A memory connected to at least one of the aforementioned processors, Includes, An electronic device wherein the memory stores instructions that can be executed by the at least one processor, and the at least one processor can perform the method according to any one of claims 1 to 10 by executing the instructions.

13. A non-temporary computer-readable storage medium storing computer instructions, wherein the computer instructions cause the computer to perform the method described in any one of claims 1 to 10.

14. A computer program, A computer program stored on a non-temporary, computer-readable medium. A computer program configured to be executed by a processor to realize the method described in any one of claims 1 to 10.

Images