Detector flutter noise suppression method and system, and corresponding detector

Abstract

The invention provides a detector flutter noise suppression method and system, and relates to the field of radiation detection. The method comprises the following steps: receiving an output signal of a detector by using a detector signal conditioning circuit and separating a flutter noise signal from the output signal; a self-adaptive noise suppression system is used for operating a self-adaptive noise suppression algorithm to process a chattering noise signal, and the chattering noise signal is used as an error signal in the self-adaptive noise suppression algorithm. When the error signal does not meet a preset minimization condition in the adaptive noise suppression algorithm, a vibration adjustment signal is output to a vibration absorber driving circuit; and adjusting the vibration of a vibration absorber installed in the detector according to the vibration adjustment signal by using a vibration absorber drive circuit. The invention also provides a detector comprising the detector flutter noise suppression system. The invention directly aims at minimizing the flutter noise in the output signal of the detector, can effectively suppress the flutter noise in the detector to a certain extent, and is simple in structure.

Description

Technical Field

[0001] The present invention relates to the field of radiation detection, and in particular, to a method and system for suppressing detector microphony noise, and a corresponding detector. Background Art

[0002] The microphony noise in the output signal of a detector can affect the detection performance. The sources of microphony noise include, but are not limited to: vibrations of the detector's refrigeration system (such as vibrations of an electric refrigeration system), rotation or vibration of a fan, vibrations of the equipment installation platform or the environment, etc. For example, in an electrically cooled high-purity germanium detector, reciprocating compressors and cold finger moving parts of the electric refrigerator can cause minute changes in the parasitic capacitance between the high-potential difference vibration electrodes of the high-purity germanium detector, thereby resulting in microphony noise in the detector output. Therefore, the deterioration of the resolution of the detector's output signal caused by microphony noise is a pain point problem that needs to be urgently solved. Summary of the Invention

[0003] In view of this, the present invention provides a method and system for suppressing detector microphony noise, and a corresponding detector, which cleverly bypasses the difficult problem of accurately measuring the vibrations that cause microphony noise in the detector (for example, the probe is in a vacuum low-temperature environment). Without a vibration sensor, directly aiming at minimizing the microphony noise in the output signal of the detector, to a certain extent, it can more directly and efficiently suppress the microphony noise in the output signal of the detector and improve the resolution of the output signal of the detector.

[0004] In the first aspect of the embodiments of the present invention, a method for suppressing detector microphony noise is provided. The method includes: receiving the output signal of the detector by a detector signal conditioning circuit and separating the microphony noise signal from the output signal of the detector; using an adaptive microphony noise suppression system to run an adaptive noise suppression algorithm to process the microphony noise signal, including: using the microphony noise signal as the error signal in the adaptive noise suppression algorithm, and when the error signal does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive microphony noise suppression system outputs a vibration adjustment signal to a vibration absorber drive circuit; and using the vibration absorber drive circuit to adjust the vibration of the vibration absorber according to the vibration adjustment signal, wherein the vibration absorber is installed in the detector.

[0005] According to an embodiment of the present invention, the method further includes: repeatedly executing the steps of receiving the output signal of the detector and separating the microphony noise signal from the output signal of the detector, running the adaptive noise suppression algorithm to process the microphony noise signal, and adjusting the vibration of the vibration absorber according to the vibration adjustment signal until the error signal meets the minimization condition. Wherein, when the error signal meets the minimization condition, the vibration of the vibration absorber is no longer adjusted.

[0006] According to an embodiment of the present invention, the adaptive noise suppression algorithm is configured to adaptively adjust the order of the filter and the coefficients of the adaptive filter.

[0007] According to an embodiment of the present invention, the step that when the error signal does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive flutter noise suppression system outputs a vibration adjustment signal to the absorber drive circuit includes: the adaptive flutter noise suppression system obtains the current vibration parameters of the absorber; the adaptive noise suppression algorithm obtains vibration adjustment parameters based on the current vibration parameters of the absorber; and the adaptive flutter noise suppression system outputs the vibration adjustment signal based on the vibration adjustment parameters.

[0008] According to an embodiment of the present invention, the step that the adaptive flutter noise suppression system obtains the current vibration parameters of the absorber includes: obtaining the vibration parameters stored locally in the adaptive flutter noise suppression system to obtain the current vibration parameters of the absorber. Wherein, after each output of the vibration adjustment signal, the adaptive flutter noise suppression system updates the vibration parameters stored locally according to the vibration adjustment parameters in the vibration adjustment signal output this time; wherein, before the first output of the vibration adjustment signal by the adaptive flutter noise suppression system, the vibration parameters stored locally are the initial vibration parameters of the absorber.

[0009] According to an embodiment of the present invention, before using the detector signal conditioning circuit to receive the output signal of the detector and separating the flutter noise signal from the output signal of the detector, the method further includes: using a vibration test unit to determine the initial drive signal of the absorber; using the absorber drive circuit to drive the vibration of the absorber according to the initial drive signal; and inputting the initial drive signal into the adaptive flutter noise suppression system, wherein the initial drive signal includes information on the initial vibration parameters of the absorber.

[0010] In a second aspect of the embodiments of the present invention, there is provided a detector flutter noise suppression system. The system includes: an absorber, a detector signal conditioning circuit, an adaptive flutter noise suppression system, and an absorber drive circuit. The absorber is installed in the detector.

[0011] The detector signal conditioning circuit is configured to receive the output signal of the detector and separate the flutter noise signal from the output signal of the detector.

[0012] The adaptive flutter noise suppression system is configured to run an adaptive noise suppression algorithm to process the flutter noise signal, including: using the flutter noise signal as the error signal in the adaptive noise suppression algorithm, and when the error signal does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive flutter noise suppression system outputs a vibration adjustment signal.

[0013] The vibration absorber driving circuit is configured to receive the vibration adjustment signal and adjust the vibration of the vibration absorber according to the vibration adjustment signal.

[0014] According to an embodiment of the present invention, when the error signal satisfies the minimization condition, the vibration of the vibration absorber is no longer adjusted.

[0015] A third aspect of an embodiment of the present invention provides a detector. The detector includes: a probe, a refrigeration system, a cold finger, and a detector microphonic noise suppression system. The cold finger connects the probe and the refrigeration system. The detector microphonic noise suppression system includes: a vibration absorber, a detector signal conditioning circuit, an adaptive microphonic noise suppression system, and a vibration absorber driving circuit.

[0016] Wherein, the vibration absorber is installed in the detector. The detector signal conditioning circuit is configured to receive the output signal of the detector and separate the microphonic noise signal from the output signal of the detector. The adaptive microphonic noise suppression system is configured to run an adaptive noise suppression algorithm to process the microphonic noise signal, including: using the microphonic noise signal as the error signal in the adaptive noise suppression algorithm, and when the error signal does not satisfy the preset minimization condition in the adaptive noise suppression algorithm, the adaptive microphonic noise suppression system outputs a vibration adjustment signal. The vibration absorber driving circuit is configured to receive the vibration adjustment signal and adjust the vibration of the vibration absorber according to the vibration adjustment signal.

[0017] According to an embodiment of the present invention, the detector includes a vacuum accommodation structure, and the inside of the vacuum accommodation structure is evacuated. The probe is disposed inside the vacuum accommodation structure, and the vibration absorber is disposed outside the vacuum accommodation structure.

[0018] According to an embodiment of the present invention, the detector is a high-purity germanium detector.

[0019] According to an embodiment of the present invention, the vibration absorber is installed at the connection between the refrigeration system and the vacuum accommodation structure.

[0020] According to an embodiment of the present invention, the refrigeration system is an electric refrigeration system.

[0021] According to an embodiment of the present invention, the detector further includes a digital spectrometer system, wherein the detector signal conditioning circuit, the adaptive microphonic noise suppression system, and the vibration absorber driving circuit are disposed in a digital multi-channel analyzer of the digital spectrometer system.

[0022] One or more of the above embodiments have the following advantages or beneficial effects:

[0023] When suppressing the microphony noise of a detector, instead of using a vibration sensor to measure the vibration in the detector, the microphony noise signal is isolated from the output signal of the detector, and then this microphony noise signal is used as the error signal in an adaptive noise suppression algorithm. By running the adaptive noise suppression algorithm (which can also be called an adaptive control algorithm), a vibration adjustment signal is output to drive the vibration absorber to adjust the amplitude, phase, frequency, etc. of the vibration. The vibration absorber generates a vibration force equal in magnitude and opposite in direction to the original vibration of the detector, thereby reducing the microphony noise caused by the vibration of the detector. Moreover, only a vibration absorber needs to be added to the detector, avoiding complex modifications to the detector structure, and the structure is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Through the following description of the embodiments of the present invention with reference to the accompanying drawings, the above and other objects, features, and advantages of the present invention will become clearer. In the drawings:

[0025] Figure 1 The structural schematic diagram of a detector according to an embodiment of the present invention is shown;

[0026] Figure 2 The structural block diagram of a detector microphony noise suppression system according to an embodiment of the present invention is shown;

[0027] Figure 3 The flowchart of a detector microphony noise suppression method according to an embodiment of the present invention is shown;

[0028] Figure 4 The flowchart of a detector microphony noise suppression method according to another embodiment of the present invention is shown;

[0029] Figure 5 The flowchart of an adaptive microphony noise suppression system running an adaptive noise suppression algorithm to process the microphony noise signal in an embodiment of the present invention is shown;

[0030] Figure 6 The processing flowchart for realizing fine adjustment of the vibration absorber in an embodiment of the present invention is shown; and

[0031] Figure 7 The structural schematic diagram of a high-purity germanium detector according to an embodiment of the present invention is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for the sake of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, obviously, one or more embodiments can also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0033] Embodiments of the present invention provide a method and system for suppressing detector microphony noise, as well as a detector including the detector microphony noise suppression system, aiming to adaptively suppress the microphony noise of the detector and at least to a certain extent solve the problem of deterioration of the detector resolution caused by the microphony noise.

[0034] According to an embodiment of the present invention, when suppressing the microphony noise of the detector, it is not necessary to use a vibration sensor to measure the vibration in the detector. Instead, the microphony noise signal is isolated from the output signal of the detector, and then this microphony noise signal is used as the error signal in the adaptive noise suppression algorithm. By running the adaptive noise suppression algorithm (which can also be called the adaptive control algorithm), a vibration adjustment signal is output to drive the vibration absorber to adjust the amplitude, phase, frequency, etc. of the vibration. By the vibration absorber generating a vibration force equal in magnitude and opposite in direction to the original vibration of the detector, the microphony noise caused by the vibration of the detector is weakened.

[0035] It can be seen that the method for suppressing microphony noise in the embodiments of the present invention cleverly bypasses the problem that the vibration causing microphony noise in the detector is difficult to accurately measure, and directly aims at minimizing the microphony noise in the output signal of the detector, providing a more direct and efficient solution strategy. Among them, the reasons why the vibration causing microphony noise in the detector is often difficult to accurately measure include many aspects: for example, the sources causing microphony noise are diverse; for another example, when measuring the vibration in the detector by a vibration sensor, in order to minimize the impact on the detection performance of the probe, usually the vibration sensor will not or cannot be set on the probe, and the microphony noise is generated due to the vibration in the detector finally acting on the probe, which will result in inaccurate measurement of the vibration. For example, in a high-purity germanium detector, the probe is located in a vacuum low-temperature environment, so it is very difficult to connect a vibration sensor to the probe, and the operation of the vibration sensor will also damage the vacuum low-temperature environment.

[0036] According to some embodiments of the present invention, the existing functions in the digital multi-channel analyzer of the detector can be reused and the functions can be extended, and at the same time, vibration absorbers are added at one or more vibration-sensitive positions preselected in the detector, then the suppression of the detector microphony noise can be effectively realized. It can not only avoid complex structural modifications, but also improve the possibility of system integration and productization, showing great technical advantages and application potential.

[0037] Figure 1 The structural schematic diagram of a detector according to an embodiment of the present invention is shown.

[0038] As Figure 1 shown, the detector 100 of this embodiment may include a probe 101, a refrigeration system 102, a cold finger 103, and a detector microphony noise suppression system 200.

[0039] The cold finger 103 connects the probe 101 and the refrigeration system 102. The refrigeration system 102 may include, but is not limited to, an electric refrigeration system.

[0040] In some embodiments, the detector 100 may further include a vacuum housing structure 104. The interior of the vacuum housing structure 104 is evacuated. Wherein, the probe 101 is disposed inside the vacuum housing structure 104 and connected to the cold finger 103, so that the probe 101 operates in a low-temperature vacuum environment. In some embodiments, both the probe 101 and the cold finger 103 are disposed inside the vacuum housing structure 104, and the vacuum housing structure 104 is connected to the refrigeration system 102, for example, by a vacuum flange. The detector 100 may be a high-purity germanium detector or other detectors (such as infrared detectors, etc.) whose probes need to operate in a low-temperature vacuum environment.

[0041] Figure 2 The structural block diagram of a detector microphonic noise suppression system 200 according to an embodiment of the present invention is shown.

[0042] Combined Figure 1 and Figure 2 As shown, the detector microphonic noise suppression system 200 may include: a detector signal conditioning circuit 210, an adaptive microphonic noise suppression system 220, a vibration absorber driving circuit 230, and a vibration absorber 240.

[0043] The detector signal conditioning circuit 210 is configured to receive the output signal of the detector 100 and separate the microphonic noise signal from the output signal of the detector 100.

[0044] In one embodiment, as Figure 1 shown, the detector signal conditioning circuit 210 may be implemented as a microphonic noise signal conditioning PCB board 211 and an AD sampling module 212. Specifically, the microphonic noise signal conditioning PCB board 211 may receive the detector output signal collected by the probe 101 and transmitted to the digital multi-channel analyzer after front-end electronics processing, and then perform DC blocking, amplification, low-pass filtering, and / or high-pass filtering on the detector output signal. Next, the AD sampling module 212 separates the microphonic noise signal caused by vibration through, for example, a Chebyshev-type digital band-pass filter implemented by using an FPGA.

[0045] The adaptive flutter noise suppression system 220 uses the flutter noise signal as the error signal e(n) in the adaptive noise suppression algorithm, and runs the adaptive noise suppression algorithm to process the flutter noise signal. When the error signal e(n) does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive flutter noise suppression system 220 outputs a vibration adjustment signal to the absorber drive circuit 230 to adjust the vibration of the absorber. When the error signal e(n) meets the minimization condition, the vibration parameters output by the absorber drive circuit 230 are no longer changed, so that the absorber 240 can maintain the vibration parameters (amplitude, phase, frequency, etc.) that make the error signal meet the minimization condition and stably output. In one embodiment, the vibration adjustment signal may be a deviation signal for adjusting the current output signal of the absorber drive circuit 230. In other embodiments, the vibration adjustment signal may also be a control signal for the output signal of the absorber drive circuit 230. In this way, when the error signal e(n) meets the preset minimization condition in the adaptive noise suppression algorithm, the vibration adjustment signal output by the adaptive flutter noise suppression system 220 no longer changes and stably outputs, so that the absorber 240 maintains stable operation.

[0046] In one embodiment, as Figure 1 shown, the adaptive flutter noise suppression system 220 can be implemented as an FPGA adaptive high-order flutter noise suppression algorithm module 221. The FPGA adaptive high-order flutter noise suppression algorithm module 221 can adopt an adaptive noise suppression algorithm such as the least mean square method LMS, and continuously adjust the amplitude, phase or frequency of the absorber 240 through the FPGA to minimize the error signal e(n). The algorithm flow of the FPGA adaptive high-order flutter noise suppression algorithm module 221 is as Figure 5 shown, where the adopted adaptive noise suppression algorithm can be set to adaptively adjust the order of the adaptive filter and the coefficients of the adaptive filter. In this way, through the two-dimensional adaption of the number of filters and the filter coefficients, not only the flutter noise generated by the vibration of the electric refrigeration system can be reduced, but also the flutter noise generated by the fan system of the detector 100 and the vibration of the equipment installation platform and the environment can be reduced.

[0047] The absorber drive circuit 230 is used to receive the vibration adjustment signal output by the adaptive flutter noise suppression system 220 (or the FPGA adaptive high-order flutter noise suppression algorithm module 221), and adjust the vibration (at least one of amplitude, phase and frequency) of the absorber 240 according to the vibration adjustment signal. For example, the absorber drive circuit 230 receives the sinusoidal pulse width modulation (SPWM) wave requirement transmitted by the FPGA adaptive high-order flutter noise suppression algorithm module 221, and drives the absorber 240 through inversion and filtering to achieve the minimum output of the detector flutter noise.

[0048] The vibration absorber 240 can be installed in the main structure of the detector 100, and can generate a vibration force opposite to the vibration at the location where it is located to cancel the original vibration influence in the detector 100. There can be one or more vibration absorbers 240 in the detector 100, and a unidirectional or three-dimensional structure can be selected. In one embodiment, the vibration absorber 240 can be installed at the connection between the refrigeration system 102 and the vacuum housing structure 104.

[0049] According to some embodiments of the present invention, components other than the vibration absorber 240 in the detector microphony noise suppression system 200 (such as the detector signal conditioning circuit 210, the adaptive microphony noise suppression system 220, and the vibration absorber drive circuit 230) can be wholly or partially integrated into an existing digital multi-channel analyzer. This can reuse some existing functions of the digital multi-channel analyzer of the detector 100 and expand the functions. Only vibration absorbers (such as micro vibration absorbers) are added to the main structure of the detector 100, avoiding complex modifications to the structure of the detector and improving the system integration level.

[0050] The following combines Figures 3 - 6 to introduce the method flow for suppressing the microphony noise of the detector 100 through the detector microphony noise suppression system 200.

[0051] Figure 3 The flowchart of the detector microphony noise suppression method according to an embodiment of the present invention is shown. This method can be executed by the detector microphony noise suppression system 200.

[0052] As Figure 3 shown, the detector microphony noise suppression method according to this embodiment can include step S310 to step S330.

[0053] In step S310, the detector signal conditioning circuit 210 is used to receive the output signal of the detector 100, and the microphony noise signal is separated from the output signal of the detector 100.

[0054] In step S320, the adaptive microphony noise suppression system 220 is used to run an adaptive noise suppression algorithm to process the microphony noise signal, including: using the microphony noise signal as the error signal in the adaptive noise suppression algorithm, and when the error signal does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive microphony noise suppression system 220 outputs a vibration adjustment signal to the vibration absorber drive circuit 230 by running the adaptive noise suppression algorithm. In one embodiment, the process of the adaptive noise suppression algorithm for processing the microphony noise signal can refer to Figure 6 for illustration.

[0055] In step S330, the vibration absorber driving circuit 230 adjusts the vibration of the vibration absorber 240 according to the vibration adjustment signal, where the vibration absorber 240 is installed in the detector 100.

[0056] Correspondingly, when the error signal satisfies the minimization condition, the adaptive flutter noise suppression system 220 no longer needs to adjust the vibration adjustment signal. At this time, the flutter noise already satisfies the minimization condition, and there is no need to adjust the output signal of the vibration absorber driving circuit. Thus, the vibration absorber operates stably in the vibration state when the flutter noise satisfies the minimization condition.

[0057] In an embodiment of the present invention, an adaptive noise suppression algorithm is adopted. The flutter noise signal in the output signal of the detector 100 is used as the error signal, and an adaptive noise suppression algorithm is used to control the vibration parameters (at least one of amplitude, phase, and frequency) of the vibration absorber located at the vibration-sensitive position of the detector 100. The original vibration in the detector 100 is cancelled by the reverse vibration of the vibration absorber, thereby realizing the suppression of the flutter noise in the output signal of the detector. The adaptive noise suppression algorithm can be but is not limited to: the adaptive narrowband feedforward filtering method.

[0058] According to an embodiment of the present invention, steps S310 to S330 can be repeatedly executed in multiple rounds in response to a trigger condition (such as manual operation trigger, timing trigger, or detector startup trigger). Among them, the number of repeated executions can be a preset number of rounds, or it can stop after the error signal satisfies the minimization condition, or it can also be continuously executed during the operation of the detector 100 without limiting the number of rounds. For example, during the operation of the detector 100, the detector signal conditioning circuit 210 continuously receives the output signal of the detector 100 to trigger this process, so as to realize the real-time adjustment of the flutter noise in the output signal of the detector 100.

[0059] In one embodiment, reference can be made to Figure 4 the process shown. Figure 4 FIG. shows a flowchart of a method for suppressing flutter noise of a detector according to another embodiment of the present invention. This method can be executed by the flutter noise suppression system 200 of the detector.

[0060] As Figure 4 shown, the method for suppressing flutter noise of the detector according to this embodiment can include steps S310, steps S321 to S323, step S330, and step S340. Among them, steps S321 to S323 are an embodiment of step S320, and steps S310 to S330 are repeatedly executed until it is determined in step S322 that the error signal satisfies the minimization condition.

[0061] In step S310, the detector signal conditioning circuit 210 receives the output signal of the detector 100, and separates the flutter noise signal from the output signal of the detector 100.

[0062] Next, in step S321, the adaptive flutter noise suppression system 220 runs an adaptive noise suppression algorithm to process the flutter noise signal.

[0063] In step S322, using the flutter noise signal as the error signal in the adaptive noise suppression algorithm, it is determined whether the error signal satisfies the preset minimization condition in the adaptive noise suppression algorithm. If so, step S340 is executed; if not, step S323 is executed.

[0064] In step S323, when the error signal does not satisfy the minimization condition, the adaptive flutter noise suppression system 220 outputs a vibration adjustment signal to the absorber drive circuit 230.

[0065] In step S330, the absorber drive circuit 230 adjusts the vibration of the absorber 240 according to the vibration adjustment signal. Then it returns to operation S310 to enter the next cycle.

[0066] In step S340, when the error signal satisfies the minimization condition, it is determined that the flutter noise suppression for this round is completed.

[0067] The process of the adaptive flutter noise suppression system 220 running the adaptive noise suppression algorithm to process the flutter noise signal in step S320 can be referred to Figure 5 as shown. Among them, the adaptive noise suppression algorithm can realize the adaptive adjustment of the number of filters and filter coefficients. When it is determined that the error signal does not satisfy the minimization condition, it can perform arithmetic processing based on information such as the deviation degree of the error signal from the minimization condition and the current vibration parameters of the absorber 240 to obtain vibration adjustment parameters, and then based on the vibration adjustment parameters, output a vibration adjustment signal to the absorber drive circuit 230. This vibration adjustment signal can be an SPWM signal, so as to trigger the absorber drive circuit 230 to adjust the vibration of the absorber 240 through the SPWM signal, such as adjusting the absorber acceleration (including but not limited to fundamental frequency acceleration, multiple frequency acceleration or N - multiple frequency acceleration, etc.).

[0068] In one embodiment, in order to achieve the rapid convergence of the flutter noise suppression process, before the detector 100 is officially operated, through targeted testing of the absorber 240 and other means, the initial vibration parameters that can keep the flutter noise level of the detector 100 at a preliminary low level can be found. In this way, at the beginning of the official operation of the detector 100, the absorber 240 starts to vibrate with these initial vibration parameters, and then makes fine adjustments according to the control of the absorber drive circuit 230, so as to more accurately suppress the flutter noise. A specific implementation method can be referred toFigure 6 Embodiment

[0069] As Figure 6 shown, the processing flow for realizing the fine-tuning of the absorber in the embodiment of the present invention includes steps S610 to S640.

[0070] In step S610, an initial drive signal of the absorber 240 is determined by using a vibration test unit. The vibration test unit may include a set of specially written vibration test programs.

[0071] In step S620, the initial drive signal is transmitted to the absorber drive circuit 230, so that the absorber drive circuit 230 drives the vibration of the absorber 240 according to the initial drive signal.

[0072] And in step S630, the initial drive signal is input into the adaptive flutter noise suppression system 220, wherein the initial drive signal includes information on the initial vibration parameters of the absorber 240. As Figure 5 shown, the initial drive signal x(0) is transmitted to the signal processing, frequency doubling signal generation, digital filtering and other links in the adaptive flutter noise suppression system 220, and the initial vibration parameters of the absorber 240 can be extracted therefrom.

[0073] Next, in step S640, after each output of the vibration adjustment signal by the adaptive flutter noise suppression system 220, the vibration parameters stored locally are updated according to the vibration adjustment parameters in the currently output vibration adjustment signal, so that when the absorber 240 needs to be fine-tuned again, the vibration parameters of the absorber 240 can be optimized based on the locally stored vibration parameters.

[0074] Figure 7 The structural schematic diagram of a high-purity germanium detector 700 according to an embodiment of the present invention is shown.

[0075] As Figure 7 shown, the high-purity germanium detector 700 may include a high-purity germanium crystal probe 701, an electric refrigeration system 702, a cold finger 103, a vacuum accommodation structure 104, a detector flutter noise suppression system 200, and a high-purity germanium digital spectrometer system 300.

[0076] The cold finger 103 is connected to the high-purity germanium crystal probe 701 and the electric refrigeration system 702.

[0077] The high-purity germanium crystal probe 701 is disposed inside the vacuum accommodation structure 104, so that the high-purity germanium crystal probe 701 operates in a low-temperature vacuum environment.

[0078] As described above Figure 2As shown, the detector microphony noise suppression system 200 may include: a detector signal conditioning circuit 210, an adaptive microphony noise suppression system 220, a vibration absorber drive circuit 230, and a vibration absorber 240. More specifically, in Figure 7 the detector signal conditioning circuit 210 includes a microphony noise signal conditioning PCB board 211 and an AD sampling module 212. The adaptive microphony noise suppression system 220 includes an FPGA adaptive high-order microphony noise suppression algorithm module 221. Among them, the functions and working processes of each part in the detector microphony noise suppression system 200 refer to the previous introduction and will not be elaborated here.

[0079] The vibration absorber 240 may be disposed at the connection between the refrigeration chassis of the electric refrigeration system 702 and the vacuum flange of the vacuum accommodating structure 104, which has a better effect on suppressing microphony noise.

[0080] In the high-purity germanium detector 700, the microphony noise signal conditioning PCB board 211, the AD sampling module 212, the FPGA adaptive high-order microphony noise suppression algorithm module 221, and the vibration absorber drive circuit 230 may be integrated into the digital multi-channel analyzer of the high-purity germanium digital spectrometer system 300. For example, the functions of the digital multi-channel analyzer of the high-purity germanium digital spectrometer system 300 may be extended or reused, so that the high-purity germanium digital spectrometer system 300 not only has the original functions, such as processing the output signal of the detector 700 to display the analysis spectrum of the output signal of the detector 700 through the digital spectrometer system, but also can suppress the microphony noise of the detector 700 by analyzing the microphony noise in the output signal of the detector, realizing a simple overall system structure and low cost of the detector 700.

[0081] The electric refrigeration high-purity germanium detector 700 provided by the embodiment of the present invention may achieve adaptive suppression of microphony noise through the detector microphony noise suppression system 200 therein. Specifically, taking the output signal of the detector 700 as a feedback signal, an oscillation adjustment signal is output through the adaptive microphony noise suppression system 220 to drive the vibration absorber 240, so that the vibration absorber 240 generates a vibration force with the same magnitude and opposite direction as the main body vibration of the electric refrigeration high-purity germanium detector 700, weakening the microphony noise caused by vibration. In this way, the detector output signal containing extremely low microphony noise can form a gamma energy spectrum with high resolution after being processed by the digital multi-channel analyzer of the high-purity germanium digital spectrometer system 300.

[0082] In the detector high and low voltage power supply circuit of the high-purity germanium digital spectrometer system 300, the low voltage power supply circuit is used to provide a low voltage DC power supply for the electronics of the high-purity germanium detector 700, and the high voltage power supply circuit provides a high voltage bias for the high-purity germanium crystal as the probe.

[0083] According to the embodiment of the present invention, adaptive microphony noise suppression may be performed with the microphony noise in the detector output signal as a feedback signal, without installing a vibration measurement unit.

[0084] In the embodiments of the present invention, the adaptive noise suppression algorithm adopted can adaptively adjust the order of the filter and the filter coefficients. It can not only weaken the vibration generated by the electric refrigerator, but also weaken the influence of the vibration of the fan system of the electrically cooled high-purity germanium detector 700, as well as the vibration of the equipment installation platform and the environment.

[0085] According to the embodiments of the present invention, the electrical structures in the detector microphony noise suppression system 200 except the vibration absorber 240 can be functionally extended on the digital multi-channel module of the original detector laboratory spectrometer, realizing a simple system structure and low cost.

[0086] Those skilled in the art can understand that the features described in the various embodiments of the present invention can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features described in the various embodiments of the present invention can be combined and / or combined in various ways. All such combinations and / or combinations fall within the scope of the present invention.

[0087] The above describes the embodiments of the present invention. However, these embodiments are only for illustrative purposes and not for limiting the scope of the present invention. Although the embodiments are described separately above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Without departing from the scope of the present invention, those skilled in the art can make various substitutions and modifications, and all such substitutions and modifications should fall within the scope of the present invention.

Claims

1. A method for suppressing detector flicker noise, wherein, The method includes: Receiving, by a detector signal conditioning circuit, an output signal of a detector and separating a flutter noise signal from the output signal of the detector; Operating, by an adaptive flutter noise suppression system, an adaptive noise suppression algorithm to process the flutter noise signal, including: using the flutter noise signal as an error signal in the adaptive noise suppression algorithm, and when the error signal does not meet a preset minimization condition in the adaptive noise suppression algorithm, the adaptive flutter noise suppression system outputs a vibration adjustment signal to a vibration absorber driving circuit; and Adjusting, by the vibration absorber driving circuit, the vibration of the vibration absorber according to the vibration adjustment signal, wherein the vibration absorber is installed in the detector.

2. The detector flicker noise suppression method according to claim 1, wherein, The method further includes: Repeatedly executing the steps of receiving the output signal of the detector and separating the flutter noise signal from the output signal of the detector, operating the adaptive noise suppression algorithm to process the flutter noise signal, and adjusting the vibration of the vibration absorber according to the vibration adjustment signal until the error signal meets the minimization condition; Wherein, when the error signal meets the minimization condition, the vibration of the vibration absorber is no longer adjusted.

3. The detector flicker noise suppression method according to claim 1, wherein, The adaptive noise suppression algorithm is set to adaptively adjust the order of an adaptive filter and the coefficients of the adaptive filter.

4. The detector flicker noise suppression method according to claim 1, wherein, The step that when the error signal does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive flutter noise suppression system outputs a vibration adjustment signal to the vibration absorber driving circuit includes: The adaptive flutter noise suppression system obtains the current vibration parameters of the vibration absorber; The adaptive noise suppression algorithm obtains vibration adjustment parameters based on the current vibration parameters of the vibration absorber; and The adaptive flutter noise suppression system outputs the vibration adjustment signal based on the vibration adjustment parameters.

5. The detector flicker noise suppression method according to claim 4, wherein, The step that the adaptive flutter noise suppression system obtains the current vibration parameters of the vibration absorber includes: Obtaining the vibration parameters stored locally in the adaptive flutter noise suppression system to obtain the current vibration parameters of the vibration absorber; Wherein, after each output of the vibration adjustment signal by the adaptive flutter noise suppression system, the vibration parameters stored locally are updated according to the vibration adjustment parameters in the vibration adjustment signal output this time; Wherein, before the first output of the vibration adjustment signal by the adaptive flutter noise suppression system, the vibration parameters stored locally are the initial vibration parameters of the vibration absorber.

6. The detector flicker noise suppression method according to claim 5, wherein, Before receiving, by the detector signal conditioning circuit, the output signal of the detector and separating the flutter noise signal from the output signal of the detector, the method further includes: Determining, by a vibration test unit, an initial driving signal of the vibration absorber; Driving, by the vibration absorber driving circuit, the vibration of the vibration absorber according to the initial driving signal; and Inputting the initial driving signal into the adaptive flutter noise suppression system, wherein the initial driving signal includes information on the initial vibration parameters of the vibration absorber.

7. A detector flicker noise suppression system, wherein, The system includes: A vibration absorber installed in a detector; A detector signal conditioning circuit, configured to receive the output signal of the detector and separate the microphonic noise signal from the output signal of the detector; An adaptive microphonic noise suppression system, configured to run an adaptive noise suppression algorithm to process the microphonic noise signal, including: using the microphonic noise signal as the error signal in the adaptive noise suppression algorithm, and when the error signal does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive microphonic noise suppression system outputs a vibration adjustment signal; and A vibration absorber driving circuit, configured to receive the vibration adjustment signal and adjust the vibration of the vibration absorber according to the vibration adjustment signal.

8. The detector popcorn noise suppression system according to claim 7, wherein, When the error signal meets the minimization condition, the vibration of the vibration absorber is no longer adjusted.

9. A detector, comprising: A probe; A refrigeration system; A cold finger, connecting the probe and the refrigeration system; And A detector microphonic noise suppression system; Wherein, the detector microphonic noise suppression system includes: A vibration absorber, installed in the detector; A detector signal conditioning circuit, configured to receive the output signal of the detector and separate the microphonic noise signal from the output signal of the detector; An adaptive microphonic noise suppression system, configured to run an adaptive noise suppression algorithm to process the microphonic noise signal, including: using the microphonic noise signal as the error signal in the adaptive noise suppression algorithm, and when the error signal does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive microphonic noise suppression system outputs a vibration adjustment signal; and A vibration absorber driving circuit, configured to receive the vibration adjustment signal and adjust the vibration of the vibration absorber according to the vibration adjustment signal.

10. The detector according to claim 9, wherein, The detector includes a vacuum accommodating structure, the interior of which is evacuated. Wherein, The probe is disposed inside the vacuum accommodating structure, and the vibration absorber is disposed outside the vacuum accommodating structure.

11. The detector according to claim 10, wherein, The detector is a high-purity germanium detector.

12. The detector according to claim 10, wherein, The vibration absorber is installed at the connection between the refrigeration system and the vacuum accommodating structure.

13. The detector according to claim 9, wherein, The refrigeration system is an electric refrigeration system.

14. The detector according to claim 9, wherein, The detector further includes a digital spectrometer system, wherein the detector signal conditioning circuit, the adaptive microphonic noise suppression system and the vibration absorber driving circuit are disposed in a digital multi-channel analyzer of the digital spectrometer system.

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