Weak signal noise shaping accumulation detection system and detection method

Abstract

The invention provides a weak signal noise shaping accumulation detection system and method, and the system comprises a noise generator which is used for generating noise with a set amplitude; the first input end of the summator is used for receiving a weak signal to be detected, the second input end of the summator is connected with the noise generator, and the summator is used for superposing the weak signal and the noise to obtain a synthetic signal; the input end of the analog-to-digital converter is connected with the output end of the summator, and the analog-to-digital converter is used for converting the synthesized signal into a digital signal; the input end of the signal accumulation and detection module is connected with the output end of the analog-to-digital converter, and the signal accumulation and detection module is used for sampling and accumulating the digital signals for multiple times so as to extract information of weak signals. According to the monitoring system provided by the invention, the detection of weak signals lower than the ADC quantization threshold is realized by superposing the noise reservation information, and the structure is simple and clear and easy to realize.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of communication technology, in particular to a noise shaping accumulation detection system and method for weak signal. BACKGROUND

[0002] In the field of digital communication and signal processing, a receiver system usually relies on an analog-to-digital converter (ADC) to convert a received analog signal into a digital signal for subsequent digital processing and detection. As a key interface between the analog domain and the digital domain, the performance of the ADC directly determines the response capability of the system to signal amplitude changes. In practical applications, especially in scenarios such as remote sensing, deep space communication, and weak target detection, the received signal is often extremely weak, and its amplitude may be lower than the minimum quantization step of the ADC, which poses a severe challenge to the traditional signal detection process.

[0003] Currently, when the amplitude of the useful signal is lower than the quantization step voltage of the ADC, the signal cannot generate effective digital code words in the sampling and quantization process, resulting in the complete loss of its amplitude information in the conversion stage. This makes it impossible to detect and recover the signal regardless of the use of any high-performance digital signal processing algorithm, as there is a lack of effective input data, which severely restricts the practical application ability of the system in low signal-to-noise ratio and high sensitivity scenarios. SUMMARY

[0004] In view of the above-mentioned defects or shortcomings in the prior art, it is desirable to provide a noise shaping accumulation detection system and method for weak signal to solve the above-mentioned problems.

[0005] The first aspect of the present application provides a noise shaping accumulation detection system for weak signal, comprising: a noise generator, configured to generate noise with a set amplitude; an adder, having a first input end configured to receive a weak signal to be detected, and a second input end connected to the noise generator, configured to superimpose the weak signal and the noise to obtain a composite signal; an analog-to-digital converter, having an input end connected to an output end of the adder, configured to convert the composite signal into a digital signal; a signal accumulation and detection module, having an input end connected to an output end of the analog-to-digital converter, configured to perform multiple sampling and accumulation processing on the digital signal to extract information of the weak signal.

[0006] According to the technical scheme provided by the embodiments of the present application, the noise amplitude generated by the noise generator is set to be greater than or equal to the quantization step voltage of the analog-to-digital converter.

[0007] According to the technical scheme provided in the embodiment of the present application, the amplitude of the noise is set to 1-5-3 times of the quantization step voltage of the analog-to-digital converter.

[0008] According to the technical scheme provided in the embodiment of the present application, the signal accumulation and detection module accumulates and processes the digital signal through discrete Fourier transform.

[0009] According to the technical scheme provided in the embodiment of the present application, the accumulation point number of the discrete Fourier transform is 2048 points.

[0010] According to the technical scheme provided in the embodiment of the present application, the amplitude of the weak signal is less than the quantization step voltage of the analog-to-digital converter.

[0011] According to the technical scheme provided in the embodiment of the present application, the noise generated by the noise generator is wideband noise, and the spectral width covers the expected frequency band of the weak signal.

[0012] According to the technical scheme provided in the embodiment of the present application, the signal accumulation and detection module detects whether a spectral peak higher than a threshold of a noise base appears in the spectrum after accumulation processing to determine the existence of the weak signal.

[0013] The second aspect of the present application provides a noise shaping accumulation detection method of a weak signal, which is realized based on the noise shaping accumulation detection system of the weak signal as described above, and includes the following steps: generating noise with a set amplitude; superimposing the noise and the received weak signal to obtain a composite signal; converting the composite signal by using an analog-to-digital converter to obtain a digital signal; accumulating and processing the digital signal to detect the weak signal from the noise background.

[0014] Compared with the prior art, the present application has the beneficial effects that: by actively superimposing noise with a set amplitude in the front end of the ADC, the weak signal originally below the quantization threshold can form a composite signal with an amplitude that can be quantized together with the noise, thereby ensuring that the information of the weak signal is not lost in the digitization process. Subsequently, the system can effectively suppress noise and enhance signal components by accumulating and processing the quantized digital signal, and finally reliably extract the information of the original weak signal from the noise background. The scheme has a simple structure, does not need to modify the existing ADC device or use complex circuits, and significantly improves the detection sensitivity and system applicability of the sub-quantization level weak signal. BRIEF DESCRIPTION OF DRAWINGS

[0015] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments made with reference to the accompanying drawings: Figure 1 Structure diagram of a noise-shaped accumulation detection system for weak signals provided for Embodiment 1 is shown in the figure; Figure 2 Step flow chart of a noise-shaped accumulation detection method for weak signals provided for Embodiment 2 is shown in the figure; Figure 3 Simulation result diagram in Embodiment 3 is shown in the figure.

[0016] Reference numerals: 10, noise generator; 20, adder; 30, analog-to-digital converter; 40, signal accumulation and detection module. DETAILED DESCRIPTION

[0017] The application will be described in further detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related application, and not to limit the application. In addition, it should be noted that only the parts related to the application are shown in the drawings for ease of description.

[0018] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and embodiments.

[0019] Embodiment 1 Please refer to Figure 1 The present embodiment provides a noise-shaped accumulation detection system for weak signals, comprising: a noise generator 10, the noise generator 10 is used to generate noise with a set amplitude; an adder 20, a first input end of the adder 20 is used to receive a weak signal to be detected, a second input end of the adder 20 is connected to the noise generator 10, and the adder 20 is used to superimpose the weak signal and the noise to obtain a composite signal; an analog-to-digital converter 30, an input end of the analog-to-digital converter 30 is connected to an output end of the adder 20, and the analog-to-digital converter 30 is used to convert the composite signal into a digital signal; a signal accumulation and detection module 40, an input end of the signal accumulation and detection module 40 is connected to an output end of the analog-to-digital converter 30, and the signal accumulation and detection module 40 is used to perform multiple sampling and accumulation processing on the digital signal to extract information of the weak signal.

[0020] Specifically, the weak signal noise shaping accumulation detection system disclosed in the embodiment comprises a noise generator 10, an adder 20, an analog-to-digital converter 30, and a signal accumulation and detection module 40, and each module forms a closed-loop cooperative architecture according to a signal processing flow. The noise generator 10 can be built by using a programmable noise generation chip, and the stable output of the noise with a set amplitude is realized through hardware circuit calibration or software parameter configuration. The output end of the noise generator 10 is connected with the second input end of the adder 20 through a shielded cable, and the shielded cable can effectively reduce the influence of external electromagnetic interference on the noise signal and ensure the consistency of the noise amplitude. The adder 20 is composed of a linear addition circuit of a high-speed operational amplifier, the first input end of the adder 20 is designed as a high-impedance interface to avoid load attenuation of the received weak signal, the two input signals form a composite signal after linear superposition in the adder, and the output end is connected with the input end of the analog-to-digital converter 30 through a buffer circuit. The buffer circuit can stabilize the amplitude characteristics of the composite signal and prevent distortion in the signal transmission process. The analog-to-digital converter 30 is selected according to the system detection requirements, and a general-purpose ADC device with a sampling rate matched with the bandwidth of the weak signal is preferentially used. For example, for a low-frequency weak signal scene, a 12-bit resolution ADC with a sampling rate not less than 1MHz can be selected. The input range of the ADC needs to be matched with the amplitude of the composite signal output by the adder to avoid clipping of the composite signal due to exceeding the range and to ensure the conversion accuracy from an analog signal to a digital signal.

[0021] The signal accumulation and detection module 40 can use FPGA or DSP as the core processing unit, realizes high-speed sampling and accumulation operation through a hardware logic circuit, and synchronously connects the input end of the module with the output end of the analog-to-digital converter 30 through an SPI interface to ensure the real-time performance and accuracy of digital signal transmission. In actual implementation, the module can preset the sampling period and the accumulation number according to the characteristics of the weak signal, the sampling process is strictly synchronized with the output rate of the ADC, the accumulation operation uses a pipeline architecture to improve the processing efficiency and ensure the accumulation of sufficient data within the effective time. In the implementation process of the whole system, the power supply circuits of the modules are all designed with filtering to reduce the interference of power supply noise on signal processing, and the installation distance between the noise generator 10 and the adder 20 is controlled within a reasonable range to avoid the electromagnetic coupling between the modules affecting the signal quality. This implementation mode not only ensures the stable functioning of the functions of the modules, but also ensures that the system can stably capture and extract weak signal information through hardware selection adaptation, signal transmission optimization and other detailed designs, without the need for substantial modification of the existing hardware architecture, and has strong engineering implementation performance.

[0022] Further, the noise amplitude generated by the noise generator 10 is set to be greater than or equal to the quantization step voltage of the analog-to-digital converter 30.

[0023] Specifically, the embodiment further optimizes the noise amplitude setting of the noise generator 10, and specifically configures the noise amplitude generated by the noise generator 10 to be greater than or equal to the quantization step voltage of the analog-to-digital converter 30. In actual implementation, the quantization step voltage parameter of the selected analog-to-digital converter 30 needs to be obtained first, which can be obtained from the data manual of the analog-to-digital converter 30 or calculated according to the full-scale amplitude and bit width. For example, if a 12-bit analog-to-digital converter 30 with a full-scale amplitude of 1Vpp is selected, the quantization step voltage can be calculated by the formula full-scale amplitude divided by 2 raised to the power of bit width, to ensure that the noise amplitude setting has a precise reference basis.

[0024] The noise generator 10 realizes the amplitude setting through parameter adjustment of a hardware circuit or numerical calibration of a software program. For example, when a programmable noise chip is used, the amplitude of the output noise can be accurately controlled by configuring the numerical value of the chip register, and at the same time, a magnitude detection feedback circuit is used to monitor the noise output amplitude in real time and make dynamic adjustments to avoid the noise amplitude deviating from the set range due to power fluctuations or environmental interference. The core function of the setting is to ensure that the amplitude of the combined signal after the superposition of the weak signal and the noise can stably reach the quantization requirement of the analog-to-digital converter 30, completely solving the problem that the weak signal cannot be effectively quantized in the traditional system because it is lower than the quantization step voltage, allowing the information of the weak signal to be completely preserved in the combined signal, providing a necessary prerequisite for the processing of the subsequent signal accumulation and detection module 40, and also providing the possibility for the flexible adaptation of the noise amplitude to analog-to-digital converters 30 of different specifications, improving the compatibility and practicality of the system.

[0025] Further, the amplitude of the noise is set to 1.5-3 times the step voltage of the analog-to-digital converter 30.

[0026] Specifically, the embodiment further specifically limits the noise amplitude setting range of the noise generator 10 to 1.5-3 times the quantization step voltage of the analog-to-digital converter 30. This range is determined through multi-scenario simulation verification and engineering measurement, which can not only ensure the effective quantization of the weak signal, but also maximize the reduction of noise interference on the subsequent signal extraction, adapting to the weak signal detection requirements in most communication and detection scenarios. In actual implementation, the full-scale amplitude, bit width and other core parameters of the analog-to-digital converter 30 need to be obtained from the official technical documents of the analog-to-digital converter 30, or the accurate quantization step voltage can be obtained through standard signal source calibration. For example, when a 12-bit analog-to-digital converter 30 with a full-scale amplitude of 1Vpp is selected, the quantization step voltage is calculated by the formula full-scale amplitude divided by 2 raised to the power of bit width, which is 2.44μV. The corresponding noise amplitude setting range is 3.66μV (2.44μVx1.5) to 7.32μV (2.44μVx3), and the specific value can be selected within this range according to the actual strength of the weak signal to be detected.

[0027] Furthermore, the signal accumulation and detection module 40 performs accumulation processing on the digital signal through discrete Fourier transform.

[0028] Specifically, this embodiment specifies that the signal accumulation and detection module 40 uses Discrete Fourier Transform (DFT) to accumulate the digital signal output by the analog-to-digital converter 30. In actual implementation, this module can use an FPGA or DSP as the core processing unit, and implement the DFT operation through hardware logic or software programming. The module is equipped with a dedicated data buffer unit to temporarily store the continuous digital signal output by the analog-to-digital converter. After the buffered data meets the operation requirements, the DFT transformation process is started to convert the digital signal with noise superimposed in the time domain into frequency domain data, thus completing the initial accumulation of signal energy.

[0029] The core advantage of DFT operations lies in their ability to concentrate the energy of weak signals at their corresponding frequency points, while the superimposed noise, due to its random nature, exhibits a uniform energy distribution in the frequency domain. Combined with the noise shaping design described earlier, after DFT accumulation, the frequency points of the weak signal will form distinct energy peaks, clearly distinguishing them from the noise floor and significantly reducing the difficulty of subsequent signal detection. This implementation method requires no complex algorithm optimization; it achieves efficient accumulation based on a mature DFT operational architecture. It is compatible with the signal processing chain of the system described above and fully leverages the noise immunity advantages of frequency domain accumulation, ensuring that the energy of the weak signal gradually becomes apparent during processing, further improving the system's detection sensitivity and stability.

[0030] Furthermore, the number of accumulated points for the discrete Fourier transform is 2048.

[0031] Specifically, this embodiment further clarifies that the number of accumulation points when the signal accumulation and detection module 40 performs the Discrete Fourier Transform (DFT) is 2048. In actual implementation, the core processing unit (FPGA or DSP) of the module needs to be pre-configured with a data buffer space of 2048 points. The buffer depth is adapted to the sampling rate of the ADC to ensure that the DFT operation is started only after the acquisition of 2048 consecutive sampling points is completed. The acquisition process is strictly synchronized with the output timing of the ADC to avoid data loss or misalignment affecting the accumulation effect. This point configuration can directly use the parameters verified by simulation without additional adjustments to the core algorithm architecture, reducing the difficulty of engineering implementation.

[0032] Furthermore, the amplitude of the weak signal is less than the quantization step voltage of the analog-to-digital converter 30.

[0033] Specifically, this embodiment specifies that the amplitude of the weak signal to be detected is less than the quantization step voltage of the analog-to-digital converter 30, which is also the core applicable scenario of this system. In actual implementation, the peak amplitude of the weak signal to be detected can be calibrated through a signal preprocessing module or a dedicated amplitude detection device to ensure that it meets the prerequisite of being lower than the ADC quantization step voltage. For example, when a 12-bit wide analog-to-digital converter 30 with a full-scale range of 1Vpp is selected, its quantization step voltage is approximately 2.44μV, and the amplitude of the weak signal to be detected can be controlled below 2.44μV.

[0034] Such low-amplitude signals, when directly converted by an ADC, will lose information because they cannot reach the quantization threshold. This system, through the noise superposition and DFT accumulation designs described earlier, provides a solution specifically for this scenario. Setting the weak signal amplitude to be less than the quantization step voltage clarifies the system's application boundaries while allowing the noise-carrying capacity to be fully utilized. This ensures that the synthesized signal can be effectively quantized by the ADC and that its characteristics can be highlighted through energy superposition in subsequent accumulation processing. Combined with simulation logic, when the weak signal meets this amplitude condition, a clear signal spectral peak can be formed in the frequency domain after complete system processing, fully verifying the system design's adaptability to this signal condition and further ensuring the targeted and reliable detection of weak signals.

[0035] Furthermore, the noise generated by the noise generator 10 is broadband noise, the spectral width of which covers the expected frequency band of the weak signal.

[0036] Specifically, this embodiment specifies that the noise generated by the noise generator 10 is broadband noise, and its spectral width can completely cover the expected frequency band of the weak signal to be detected. In actual implementation, the expected frequency band range of the weak signal needs to be determined according to the application scenario. This range can be preset in conjunction with the communication protocol and the signal characteristics of the target being detected, or it can be calibrated in reverse by the filtering parameters of the front-end receiving circuit. For example, if the weak signal to be detected is a low-frequency signal of 1kHz-100kHz, the broadband noise spectrum output by the noise generator 10 must at least cover the 1kHz-100kHz range.

[0037] The noise generator 10 can be built using a dedicated broadband noise source chip or a resistive thermal noise amplifier circuit. By optimizing the frequency response characteristics of the circuit, it ensures that the noise signal amplitude is evenly distributed within the target frequency band, avoiding insufficient noise amplitude in local frequency bands. If a chip solution is used, the noise spectrum range can be extended by configuring the chip's bandwidth control pin; if a discrete circuit solution is used, the effective noise bandwidth can be widened by adjusting the feedback resistor and capacitor parameters of the amplifier circuit. The core advantage of this design is that the spectral coverage characteristics of broadband noise ensure that weak signals can be effectively superimposed with noise throughout their entire frequency band, avoiding the inability of some frequency bands to be quantized by the analog-to-digital converter 30 due to the misalignment of the noise spectrum and signal frequency band. At the same time, combined with subsequent DFT accumulation processing, the energy of weak signals at their corresponding frequency points is fully concentrated, further improving the distinction between signal peaks and noise floor, ensuring that the system can stably detect weak signals at different frequency points, and enhancing the system's adaptability to diverse signal scenarios.

[0038] Furthermore, the signal accumulation and detection module 40 determines the presence of the weak signal by detecting whether a spectral peak higher than the noise floor appears in the spectrum after accumulation processing.

[0039] Specifically, this embodiment clarifies the judgment logic of the signal accumulation and detection module 40: by detecting whether there are spectral peaks in the frequency domain data after DFT accumulation processing that are higher than the noise floor threshold, the presence of a weak signal is confirmed. In actual implementation, the module first estimates the noise floor of the accumulated frequency domain data. This can be done by using the average energy of the signal-free frequency bands in the statistical frequency domain, or by calculating the statistical value of the noise energy across the entire domain using a sliding window algorithm. Then, a preset safety factor is superimposed as the judgment threshold. The threshold parameter can be adjusted by software calibration according to the actual environmental noise intensity to ensure anti-interference capability.

[0040] Example 2 Please refer to Figure 2 Based on Embodiment 1 above, this embodiment provides a method for detecting noise shaping accumulation of weak signals, implemented using the noise shaping accumulation detection system for weak signals as described in Embodiment 1, including: S100: Generates noise of a set amplitude; S200: The noise is superimposed with the received weak signal to obtain a synthesized signal; S300: The synthesized signal is converted using the analog-to-digital converter 30 to obtain a digital signal; S400: The digital signal is accumulated and processed to detect the weak signal from the background noise.

[0041] Specifically, such as Figure 2As shown, the noise shaping and accumulation detection method for weak signals disclosed in this embodiment is implemented based on the detection system of Embodiment 1. Its steps and processes are deeply adapted to the functions of each module of the system, ensuring efficient collaboration across the entire chain from signal input to result determination. In actual implementation, each module of the system is first started and the parameters are initialized. Based on the quantization step voltage of the selected analog-to-digital converter 30, the expected frequency band and amplitude characteristics of the weak signal to be detected, the parameters are configured through the control interface of the noise generator 10 to generate broadband noise with an amplitude of 1.5-3 times the quantization step voltage. The noise spectrum completely covers the expected frequency band of the weak signal, while ensuring that the amplitude of the weak signal to be detected is less than the quantization step voltage of the analog-to-digital converter 30, laying the parameter foundation for subsequent processing.

[0042] Next, the weak signal to be detected is connected to the first input terminal of adder 20 via the front-end receiving link, and linearly superimposed with the broadband noise output to the second input terminal of noise generator 10. Adder 20 avoids signal distortion through internal high-fidelity operation circuit. The output synthesized signal meets the quantization requirements of analog-to-digital converter 30 due to the superposition of adaptive noise. Subsequently, the synthesized signal is transmitted to analog-to-digital converter 30, which completes the conversion of analog signal to digital signal according to the preset sampling rate. The converted digital signal is written to the buffer unit of signal accumulation and detection module 40 in real time through synchronous transmission interface. After the module accumulates and stores 2048 consecutive sampling points in the buffer unit, it automatically starts the discrete Fourier transform (DFT) operation to convert the time-domain digital signal into frequency-domain data. Then, by statistically analyzing the average energy of the no-signal frequency band in the frequency domain and superimposing a safety factor, the noise floor judgment threshold is determined. Finally, the energy amplitude of the frequency domain data is compared point by point. If a spectral peak that is continuously higher than the threshold appears at a certain frequency point, and the spectral peak characteristics match the frequency band of the weak signal, then the weak signal is determined to exist.

[0043] Based on the system architecture design of Example 1, each step corresponds one-to-one with the functions of the noise generator 10, adder 20, analog-to-digital converter 30 and signal accumulation and detection module 40. It solves the core problem of weak signals being unquantifiable by noise shaping, and achieves accurate signal extraction by using DFT accumulation and spectral peak determination. The steps are tightly connected and highly operable in engineering. It can be adapted to various weak signal detection scenarios without complex additional configuration, giving full play to the synergistic advantages of the system and method.

[0044] Example 3 This embodiment verifies the effectiveness of the noise shaping and accumulation detection system and method for weak signals of this application through a specific simulation experiment. The experimental parameters are based on the simulation settings, and the experimental results correspond to Figure 3 (simulation result diagram). The experimental configuration, process and result analysis are described in detail below.

[0045] The experiment used a 12-bit general-purpose analog-to-digital converter (ADC) with a full-scale amplitude set to 1Vpp. The quantization step voltage was calculated to be 2.44 × 10⁻⁴ V according to the formula. The weak signal to be detected was generated by a high-precision signal source with an amplitude set to 0.8 × 10⁻⁴ V. This amplitude is less than the quantization step voltage of the ADC and represents a weak signal that traditional detection systems cannot effectively quantize. Its expected frequency band is 1kHz-10kHz. A programmable broadband noise source was used to generate broadband noise with an amplitude of 0.5 × 10⁻³ V. This amplitude is approximately 2.05 times the ADC quantization step voltage, falling within the 1.5-3 times range specified in Example 1, and the noise spectrum width covers the expected frequency band of the weak signal from 1kHz to 10kHz.

[0046] The experiment was divided into two groups: the control group did not use the noise generator and directly input the weak signal into the ADC for conversion and accumulation detection; the experimental group followed the method of this application, first superimposing the weak signal with broadband noise of set parameters through an adder, then inputting the synthesized signal into the ADC for conversion, and finally the signal accumulation and detection module performed 2048-point DFT accumulation and spectral peak determination. Figure 3 The left column shows the experimental results of the control group: The first figure shows the time-domain waveform when a weak signal is directly input. Because the signal amplitude is lower than the ADC quantization step voltage, the digital signal after ADC conversion is all zero, and the time-domain waveform is a horizontal straight line; the second figure is the time-domain waveform of the converted digital signal, with no effective signal fluctuation; the third figure is the frequency domain spectrum after DFT accumulation, which does not show any spectral peaks higher than the noise floor, proving that the traditional method cannot detect this weak signal. (Appendix) Figure 3 The right column shows the experimental results of the experimental group: The first figure is the time-domain waveform of the synthesized signal after the weak signal and broadband noise are superimposed. It can be seen that the signal fluctuates significantly due to the noise superposition, and the amplitude meets the ADC quantization requirements; The second figure is the time-domain waveform of the digital signal after the synthesized signal is converted by the ADC. It is no longer zero, and the weak signal information is preserved in the noise background; The third figure is the frequency domain spectrum after 2048-point DFT accumulation. A significant spectral peak appears at the frequency point (5kHz) corresponding to the weak signal. The amplitude of the spectral peak is more than 12dB higher than the noise floor, and the width of the spectral peak matches the frequency band characteristics of the weak signal. The spectral peak determination algorithm confirms that the spectral peak is the energy peak corresponding to the target weak signal.

[0047] Experimental results show that the proposed solution, by superimposing broadband noise at 1.5-3 times the quantization step voltage, successfully quantizes weak signals below the ADC quantization threshold. Following 2048-point DFT accumulation and spectral peak determination, weak signal information can be accurately extracted from the noise background. This experiment directly verifies that: a reasonable noise amplitude setting ensures the effectiveness of signal quantization; the spectral coverage characteristics of broadband noise guarantee full-band signal superposition; and DFT accumulation and spectral peak determination achieve effective separation of signal and noise. This fully demonstrates that the proposed solution can solve the technical problem of weak signal detection in traditional systems, possessing reliable practicality and engineering feasibility.

[0048] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A noise-shaped integration detection system for weak signals, characterized in that The application relates to a weak signal noise shaping accumulation detection system, which comprises the following parts: a noise generator (10) for generating noise with a set amplitude; a first input end of an adder (20) for receiving a weak signal to be detected, and a second input end connected with the noise generator (10) for superimposing the weak signal with the noise to obtain a composite signal; an analog-digital converter (30) with an input end connected with an output end of the adder (20) for converting the composite signal into a digital signal; a signal accumulation and detection module (40) with an input end connected with an output end of the analog-digital converter (30) for sampling and accumulating the digital signal multiple times to extract information of the weak signal.

2. The noise-shaped integration detection system for weak signals of claim 1, wherein, The noise amplitude generated by the noise generator (10) is set to be greater than or equal to a quantization step voltage of the analog-digital converter (30).

3. The method of claim 2, wherein, The noise amplitude is set to be 1.5-3 times of the quantization step voltage of the analog-digital converter (30).

4. The method of claim 1, wherein, The signal accumulation and detection module (40) accumulates the digital signal through discrete Fourier transform.

5. The method of claim 4, wherein, The accumulation point number of the discrete Fourier transform is 2048.

6. The method of claim 1, wherein, The amplitude of the weak signal is less than the quantization step voltage of the analog-digital converter (30).

7. The method of claim 1, wherein, The noise generated by the noise generator (10) is broadband noise, and the frequency spectrum width covers the expected frequency band of the weak signal.

8. The method of claim 7, wherein, The signal accumulation and detection module (40) judges the existence of the weak signal by detecting whether a spectral peak higher than a threshold of a noise base appears in a spectrum after accumulation processing.

9. A noise-shaped accumulation detection method of a weak signal, characterized by, The application further discloses a weak signal noise shaping accumulation detection system based on any one of claims 1-8, which comprises the following steps: generating noise with a set amplitude; superimposing the noise with a received weak signal to obtain a composite signal; converting the composite signal into a digital signal through an analog-digital converter (30); accumulating the digital signal to detect the weak signal from a noise background.

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