Method and system for flicker noise suppression in a detector, and corresponding detector

Abstract

The application provides a detector microphonic 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 a detector signal conditioning circuit and separating a microphonic noise signal from the output signal; processing the microphonic noise signal by an adaptive microphonic noise suppression system running an adaptive noise suppression algorithm, wherein the microphonic noise signal is used as an error signal in the adaptive noise suppression algorithm, and a vibration adjustment signal is output to a vibration absorber driving circuit when the error signal does not satisfy a preset minimization condition in the adaptive noise suppression algorithm; and adjusting the vibration of a vibration absorber installed in the detector according to the vibration adjustment signal by the vibration absorber driving circuit. The application also provides a detector comprising a detector microphonic noise suppression system. The application directly aims at minimizing the microphonic noise in the output signal of the detector, can effectively suppress the microphonic noise in the detector to a certain extent, and has a simple structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radiation detection, and in particular to a detector microphonic noise suppression method and system, and a corresponding detector. BACKGROUND

[0002] Microphonic noise in the output signal of a detector can affect the detection performance. The sources of microphonic noise include, but are not limited to, vibration of the detector's refrigeration system (e.g. vibration of an electric refrigeration system), rotation or vibration of a fan, vibration of the equipment mounting platform or environment, etc. For example, in an electric refrigeration high-purity germanium detector, the reciprocating compressor and cold finger moving parts of the electric refrigerator can cause small changes in the parasitic capacitance between the high-purity germanium detector high-potential difference vibration electrodes, thereby causing microphonic noise in the output of the detector. Therefore, the resolution of the output signal of the detector deteriorated by microphonic noise is a problem that needs to be solved urgently. SUMMARY

[0003] In view of this, the present application provides a detector microphonic noise suppression method and system, and a corresponding detector, which ingeniously bypasses the problem of difficult accurate measurement of vibration causing microphonic noise in the detector (e.g. the probe is located in a vacuum low-temperature environment), does not require a vibration sensor, directly targets minimizing microphonic noise in the output signal of the detector, and can more directly and efficiently suppress microphonic noise in the output signal of the detector to some extent, thereby improving the resolution of the output signal of the detector.

[0004] In a first aspect, the present application provides a detector microphonic noise suppression method. The method comprises: receiving an output signal of a detector using a detector signal conditioning circuit and separating a microphonic noise signal from the output signal of the detector; processing the microphonic noise signal using an adaptive microphonic noise suppression system running an adaptive noise suppression algorithm, including: using the microphonic noise signal as an error signal in the adaptive noise suppression algorithm, and when the error signal does not satisfy a preset minimization condition in the adaptive noise suppression algorithm, the adaptive microphonic noise suppression system outputs a vibration adjustment signal to a vibration absorber driving circuit; and adjusting the vibration of a vibration absorber according to the vibration adjustment signal using the vibration absorber driving circuit, wherein the vibration absorber is installed in the detector.

[0005] According to an embodiment of the present application, the method further comprises: repeatedly performing the steps of receiving an output signal of a detector and separating a microphonic noise signal from the output signal of the detector, processing the microphonic noise signal using an adaptive noise suppression algorithm, and adjusting the vibration of a vibration absorber according to the vibration adjustment signal until the error signal satisfies the minimization condition. When the error signal satisfies the minimization condition, the vibration of the vibration absorber is no longer adjusted.

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

[0007] According to an embodiment of the present application, when the error signal does not satisfy the preset minimization condition in the adaptive noise suppression algorithm, the adaptive hum noise suppression system outputs a vibration adjustment signal to the absorber driving circuit, including: the adaptive hum noise suppression system acquires the current vibration parameter of the absorber; the adaptive noise suppression algorithm obtains a vibration adjustment parameter based on the current vibration parameter of the absorber; and the adaptive hum noise suppression system outputs the vibration adjustment signal based on the vibration adjustment parameter.

[0008] According to an embodiment of the present application, the adaptive hum noise suppression system acquires the current vibration parameter of the absorber, including: acquiring the vibration parameter stored locally by the adaptive hum noise suppression system to obtain the current vibration parameter of the absorber. Wherein, after each output of the vibration adjustment signal, the adaptive hum noise suppression system updates the locally stored vibration parameter according to the vibration adjustment parameter in the vibration adjustment signal output this time; wherein, before the adaptive hum noise suppression system outputs the vibration adjustment signal for the first time, the locally stored vibration parameter is the initial vibration parameter of the absorber.

[0009] According to an embodiment of the present application, before the detector signal conditioning circuit receives the output signal of the detector and separates the hum noise signal from the output signal of the detector, the method further comprises: determining an initial driving signal of the absorber by using a vibration test unit; driving the vibration of the absorber by the absorber driving circuit according to the initial driving signal; and inputting the initial driving signal to the adaptive hum noise suppression system, wherein the initial driving signal includes information of the initial vibration parameter of the absorber.

[0010] According to a second aspect of the embodiments of the present application, a detector hum noise suppression system is provided. The system comprises: an absorber, a detector signal conditioning circuit, an adaptive hum noise suppression system and an absorber driving 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 hum noise signal from the output signal of the detector.

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

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

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

[0015] In a third aspect, the present application provides a detector. The detector comprises 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 comprises an absorber, a detector signal conditioning circuit, an adaptive microphonic noise suppression system, and an absorber driving circuit.

[0016] The absorber is mounted in the detector. The detector signal conditioning circuit is configured to receive an output signal of the detector and separate a microphonic 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 signal, including taking the microphonic signal as an error signal in the adaptive noise suppression algorithm, and outputting a vibration adjustment signal when the error signal does not satisfy a preset minimization condition in the adaptive noise suppression algorithm. The absorber driving circuit is configured to receive the vibration adjustment signal and adjust the vibration of the absorber according to the vibration adjustment signal.

[0017] According to the embodiment of the present application, the detector comprises a vacuum containment structure, the inside of which is evacuated. The probe is disposed inside the vacuum containment structure, and the absorber is disposed outside the vacuum containment structure.

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

[0019] According to the embodiment of the present application, the absorber is mounted at a connection between the refrigeration system and the vacuum containment structure.

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

[0021] According to the embodiment of the present application, the detector further comprises a digital spectrometer system, wherein the detector signal conditioning circuit, the adaptive microphonic noise suppression system, and the absorber driving circuit are disposed in a digital multichannel analyzer of the digital spectrometer system.

[0022] The one or more embodiments have the following advantages or beneficial effects:

[0023] In the case of suppressing the microphonic noise of the detector, instead of measuring the vibration in the detector by the vibration sensor, the microphonic noise signal is isolated from the output signal of the detector, and then the microphonic noise signal is taken as the error signal in the adaptive noise suppression algorithm, and the vibration adjustment signal is outputted by running the adaptive noise suppression algorithm (also called adaptive control algorithm), so as to drive the vibration absorber to adjust the amplitude, phase or frequency of the vibration, and the vibration absorber generates the vibration force which is equal in size and opposite in direction to the original vibration of the detector, so as to weaken the microphonic noise caused by the vibration of the detector. Moreover, only the vibration absorber needs to be added in the detector, and the complex modification of the structure of the detector is avoided, and the structure is simple. BRIEF DESCRIPTION OF DRAWINGS

[0024] The above and other objects, features and advantages of the present application will become more apparent from the following description of embodiments of the present application taken in conjunction with the accompanying drawings, in which:

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

[0026] Figure 2 A structural block diagram of a detector microphonic noise suppression system according to an embodiment of the present application is shown;

[0027] Figure 3 A flow chart of a detector microphonic noise suppression method according to an embodiment of the present application is shown;

[0028] Figure 4 A flow chart of a detector microphonic noise suppression method according to another embodiment of the present application is shown;

[0029] Figure 5 A flow chart of the adaptive microphonic noise suppression system running the adaptive noise suppression algorithm to process the microphonic noise signal in an embodiment of the present application is shown;

[0030] Figure 6 A processing flow chart for realizing the fine adjustment of the vibration absorber in an embodiment of the present application is shown; and

[0031] Figure 7 A structural schematic diagram of a high-purity germanium detector according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0032] Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings. It is to be understood, however, that these descriptions are merely exemplary and are intended to provide a thorough and complete disclosure of the present application as defined by the appended claims. Accordingly, various modifications and changes can be made in the embodiments without departing from the scope of the present application as defined by the appended claims. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without these specific details. In other instances, well-known structures and techniques have not been shown in detail in order not to obscure the understanding of this application.

[0033] Embodiments of the present application provide a detector microphonic noise suppression method and system, and a detector comprising the detector microphonic noise suppression system, aiming to adaptively suppress the microphonic noise of the detector and at least partially solve the problem of resolution degradation of the detector caused by the microphonic noise.

[0034] According to embodiments of the present application, when suppressing the microphonic noise of the detector, instead of measuring the vibration in the detector by a vibration sensor, the microphonic noise signal is isolated from the output signal of the detector, and then the microphonic noise signal is taken as an error signal in an adaptive noise suppression algorithm, and a vibration adjustment signal is output by running the adaptive noise suppression algorithm (which can also be called an adaptive control algorithm) to drive the vibration absorber to adjust the amplitude, phase or frequency of the vibration, so as to generate a vibration force in the opposite direction of the original vibration in the detector to weaken the microphonic noise caused by the vibration in the detector.

[0035] As can be seen, the way of suppressing the microphonic noise in the embodiments of the present application ingeniously bypasses the difficulty that the vibration causing the microphonic noise in the detector is difficult to be accurately measured, and directly takes minimizing the microphonic noise in the output signal of the detector as the target, thereby providing a more direct and efficient solution strategy. The reasons why the vibration causing the microphonic noise in the detector is difficult to be accurately measured include various aspects: for example, the source causing the microphonic noise is diverse; for another example, when measuring the vibration in the detector by a vibration sensor, in order to minimize the impact on the performance of the probe, the vibration sensor is usually not or cannot be arranged on the probe, while the microphonic noise is caused by 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 on 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 application, the existing functions in the digital multi-channel analyzer of the detector can be reused and expanded, and at the same time, vibration absorbers are added at one or more vibration sensitive positions selected in advance in the detector, so that the suppression of the microphonic noise of the detector can be effectively realized, which not only avoids complex structural changes, but also improves the possibility of system integration and productization, and shows great technical advantages and application potential.

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

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

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

[0040] In some embodiments, the probe 100 can further include a vacuum containment structure 104. The interior of the vacuum containment structure 104 is evacuated, wherein the probe 101 is disposed in the interior of the vacuum containment structure 104 and connected with the cold finger 103, so that the probe 101 works in a low-temperature vacuum environment. In some embodiments, the probe 101 and the cold finger 103 are both disposed in the interior of the vacuum containment structure 104, and the vacuum containment structure 104 is connected with the refrigeration system 102, for example, through a vacuum flange. The probe 100 can be a high-purity germanium probe, or other probes (such as infrared probes, etc.) that require the probe to work in a low-temperature vacuum environment.

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

[0042] In combination Figure 1 and Figure 2 As shown, the probe microphonic noise suppression system 200 can include a probe signal conditioning circuit 210, an adaptive microphonic noise suppression system 220, a vibration absorber drive circuit 230, and a vibration absorber 240.

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

[0044] In one embodiment, as shown in Figure 1 The probe signal conditioning circuit 210 can 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 can receive the probe output signal collected by the probe 101 and transmitted to a digital multi-channel analyzer after front-end electronic processing, and then perform direct current isolation, amplification, low-pass filtering, and / or high-pass filtering on the probe output signal. Next, the AD sampling module 212 separates the microphonic noise signal caused by vibration through a Chebyshev digital bandpass filter implemented by, for example, an FPGA.

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

[0046] In one embodiment, such as Figure 1 As shown, the adaptive jitter noise suppression system 220 can be implemented as an FPGA adaptive high-order jitter noise suppression algorithm module 221. The FPGA adaptive high-order jitter noise suppression algorithm module 221 can employ adaptive noise suppression algorithms such as the Least Mean Square Error (LMS) method, continuously adjusting the amplitude, phase, or frequency of the vibration absorber 240 via the FPGA to minimize the error signal e(n). The algorithm flow of the FPGA adaptive high-order jitter noise suppression algorithm module 221 is as follows: Figure 5 As shown, the adaptive noise suppression algorithm used can be set to adaptively adjust the order of the filter and the coefficients of the filter. In this way, through the dual-dimensional adaptation of the number of filters and the filter coefficients, not only can the vibration noise generated by the vibration of the electric cooling system be reduced, but also the vibration noise generated by the fan system of the detector 100, the equipment installation platform and the environment can be reduced.

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

[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 its location to counteract the original vibration effects in the detector 100. The detector 100 may have one or more vibration absorbers 240, which can be unidirectional or three-dimensional structures. In one embodiment, the vibration absorber 240 can be installed at the connection between the cooling system 102 and the vacuum containment structure 104.

[0049] According to some embodiments of the present invention, the components of the detector jitter noise suppression system 200 other than the vibration absorber 240 (such as the detector signal conditioning circuit 210, the adaptive jitter noise suppression system 220, and the vibration absorber drive circuit 230) can be fully or partially integrated into an existing digital multichannel analyzer. This allows for the reuse and functional expansion of some existing functions of the digital multichannel analyzer of the detector 100, adding only a vibration absorber (such as a miniature vibration absorber) to the main structure of the detector 100, avoiding complex modifications to the detector structure, and improving the level of system integration.

[0050] The following combination Figures 3-6 This paper introduces a method for suppressing the jitter noise of detector 100 using detector jitter noise suppression system 200.

[0051] Figure 3 A flowchart of a detector jitter noise suppression method according to an embodiment of the present invention is shown. This method can be performed by a detector jitter noise suppression system 200.

[0052] like Figure 3 As shown, the detector jitter noise suppression method according to this embodiment may include steps S310 to S330.

[0053] In step S310, the detector signal conditioning circuit 210 receives the output signal of the detector 100 and separates the jitter noise signal from the output signal of the detector 100.

[0054] In step S320, the adaptive vibration noise suppression system 220 runs an adaptive noise suppression algorithm to process the vibration noise signal, including: using the vibration noise signal as an error signal in the adaptive noise suppression algorithm; when the error signal does not meet the preset minimization condition in the adaptive noise suppression algorithm, the adaptive vibration 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 processing the vibration noise signal can be referred to... Figure 6 The illustration.

[0055] At step S330, the vibration of the vibration absorber 240 is adjusted by the vibration absorber driving circuit 230 according to the vibration adjustment signal, wherein the vibration absorber 240 is installed in the detector 100.

[0056] Correspondingly, when the error signal satisfies the minimization condition, the adaptive microphonic noise suppression system 220 no longer needs to adjust the vibration adjustment signal, at this time the microphonic noise has satisfied the minimization condition, and the output signal of the vibration absorber driving circuit does not need to be adjusted, so that the vibration absorber operates stably in the vibration state when the microphonic noise satisfies the minimization condition.

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

[0058] According to the embodiment of the present application, the steps S310-S330 can be repeatedly executed for multiple rounds in response to a trigger condition (such as manual operation trigger or timing trigger or detector start trigger). The number of repeated rounds can be a preset number, or can be stopped after the error signal satisfies the minimization condition, or can be executed all the time during the operation of the detector 100 without limitation on the number of rounds. For example, the detector signal conditioning circuit 210 continuously receives the output signal of the detector 100 to trigger the flow during the operation of the detector 100, so as to realize real-time adjustment of the microphonic noise in the output signal of the detector 100.

[0059] In one embodiment, the flow shown in Figure 4 may be referred to. Figure 4 A flowchart of a detector microphonic noise suppression method according to another embodiment of the present application is shown. The method can be executed by the detector microphonic noise suppression system 200.

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

[0061] At step S310, the output signal of the detector 100 is received by the detector signal conditioning circuit 210, and the microphonic signal is separated from the output signal of the detector 100

[0062] Next, at step S321, the adaptive microphonic suppression system 220 runs the adaptive noise suppression algorithm to process the microphonic signal.

[0063] At step S322, the microphonic signal is used as the error signal in the adaptive noise suppression algorithm, and it is determined whether the error signal satisfies the preset minimization condition in the adaptive noise suppression algorithm. If yes, step S340 is executed; if no, step S323 is executed.

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

[0065] At step S330, the absorber driving 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 round of loop.

[0066] At step S340, when the error signal satisfies the minimization condition, it is determined that the microphonic suppression of this round is completed.

[0067] The flow of the adaptive microphonic suppression system 220 running the adaptive noise suppression algorithm to process the microphonic signal in step S320 can refer to the flow shown in Figure 5 The adaptive noise suppression algorithm can realize adaptive adjustment of the number of filters and filter coefficients. When it is determined that the error signal does not satisfy the minimization condition, the vibration adjustment parameter can be obtained based on the deviation of the error signal from the minimization condition and the current vibration parameters of the absorber 240, and then the vibration adjustment signal can be output to the absorber driving circuit 230 based on the vibration adjustment parameter. The vibration adjustment signal can be an SPWM signal, so that the vibration adjustment signal triggers the absorber driving circuit 230 to adjust the vibration of the absorber 240, such as adjusting the absorber acceleration (including but not limited to the fundamental frequency acceleration, the multiple frequency acceleration, or the N multiple frequency acceleration, etc.).

[0068] In an embodiment, in order to realize the fast convergence of the microphonic suppression process, the initial vibration parameters that can maintain the microphonic level of the detector 100 at a preliminary low level can be found through targeted testing of the absorber 240 before the detector 100 is formally run. In this way, the absorber 240 starts to vibrate with the initial vibration parameters at the beginning of the formal operation of the detector 100, and then the vibration is fine-tuned according to the control of the absorber driving circuit 230, so as to more accurately suppress the microphonic noise. A specific implementation can refer toFigure 6 Embodiment.

[0069] As Figure 6 shown, the process flow for fine-tuning the vibration absorber in the embodiment of the present application includes steps S610-S640.

[0070] At step S610, the initial driving signal of the vibration absorber 240 is determined by a vibration test unit. The vibration test unit can include a set of vibration test programs specially written.

[0071] At step S620, the initial driving signal is transmitted to the vibration absorber driving circuit 230, so that the vibration absorber 240 is driven according to the initial driving signal by the vibration absorber driving circuit 230.

[0072] And at step S630, the initial driving signal is input to the adaptive microphonic noise suppression system 220, wherein the initial driving signal includes information of the initial vibration parameters of the vibration absorber 240. As Figure 5 shown, the initial driving signal x(0) is transmitted to the signal processing and frequency multiplication signal generation and digital filtering links in the adaptive microphonic noise suppression system 220, from which the initial vibration parameters of the vibration absorber 240 can be extracted.

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

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

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

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

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

[0078] As previously Figure 2As shown, the detector microphonic noise suppression system 200 can 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. Figure 7 The detector signal conditioning circuit 210 in the embodiment includes a microphonic signal conditioning PCB board 211 and an AD sampling module 212. The adaptive microphonic noise suppression system 220 includes an FPGA adaptive high-order microphonic noise suppression algorithm module 221. The functions and working processes of the various parts in the detector microphonic noise suppression system 200 are described above and will not be repeated here.

[0079] The vibration absorber 240 can be arranged at the connection between the refrigeration machine case of the electric refrigeration system 702 and the vacuum flange of the vacuum containment structure 104, so that the microphonic noise suppression effect is better.

[0080] In the high-purity germanium detector 700, the microphonic signal conditioning PCB board 211, the AD sampling module 212, the FPGA adaptive high-order microphonic noise suppression algorithm module 221, and the vibration absorber driving circuit 230 can be integrated into the digital multichannel analyzer of the high-purity germanium digital spectrometer system 300. For example, the digital multichannel analyzer of the high-purity germanium digital spectrometer system 300 can be functionally extended or functionally multiplexed, so that the high-purity germanium digital spectrometer system 300 has both 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, and the function of suppressing the microphonic noise of the detector 700 by analyzing the microphonic noise in the output signal of the detector, so as to realize the simple overall system structure and low cost of the detector 700.

[0081] The electric refrigeration high-purity germanium detector 700 provided by the embodiment can realize adaptive microphonic noise suppression through the detector microphonic noise suppression system 200 therein. Specifically, the output signal of the detector 700 is used as a feedback signal, and a vibration adjustment signal is output by the adaptive microphonic noise suppression system 220 to drive the vibration absorber 240, so that the vibration absorber 240 generates a vibration force equal in size and opposite in direction to the main vibration of the electric refrigeration high-purity germanium detector 700, thereby reducing the microphonic noise caused by the vibration. In this way, the detector output signal containing extremely low microphonic noise can form a gamma spectrum with high resolution after being processed by the digital multichannel analyzer of the high-purity germanium digital spectrometer system 300.

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

[0083] According to the embodiment, the microphonic noise in the detector output signal can be used as a feedback signal for adaptive microphonic noise suppression, and a vibration measurement unit does not need to be installed.

[0084] The adaptive noise suppression algorithm used in the embodiments of the present application can adaptively adjust the order of the filter and adaptively adjust the filter coefficients, so as to not only weaken the vibration generated by the electric refrigerator, but also weaken the influence of the vibration of the fan system of the electric refrigerator high-purity germanium detector 700 and the vibration of the equipment installation platform and the environment.

[0085] According to the embodiments of the present application, the electrical structure of the detector microphonic noise suppression system 200 except the vibration absorber 240 can be functionally extended in the original detector laboratory spectrometer digital multi-channel module, so as to realize simple system structure and low cost.

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

[0087] The embodiments of the present application are described above. However, these embodiments are only for illustrative purposes, and are not intended to limit the scope of the present application. Although each embodiment is described above, this does not mean that the measures in each embodiment cannot be used advantageously in combination. Those skilled in the art can make various substitutions and modifications without departing from the scope of the present application, and these substitutions and modifications should fall within the scope of the present application.

Claims

1. A detector, wherein, The detector is a high-purity germanium detector, and the detector includes: probe; Electric refrigeration system; The cold finger connects the probe and the electric cooling system; A vacuum containment structure, wherein the interior of the vacuum containment structure is evacuated, and the probe is disposed inside the vacuum containment structure; and Detector jitter noise suppression system; The detector jitter noise suppression system includes: A vibration absorber is installed at the connection between the electro-cooling system and the vacuum containment structure in the detector; A detector signal conditioning circuit is used to receive the output signal of the detector and separate the jitter noise signal from the output signal of the detector; An adaptive flutter noise suppression system is used to run 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; and A vibration absorber drive circuit is used to receive the vibration adjustment signal and adjust the vibration of the vibration absorber according to the vibration adjustment signal; The detector signal conditioning circuit includes a flutter noise signal conditioning PCB board and an AD sampling module. The flutter noise signal conditioning PCB board receives the detector output signal, which is acquired by the probe, processed by the front-end electronics, and then transmitted to the digital multichannel analyzer. The output signal is then subjected to DC blocking, amplification, low-pass filtering, and / or high-pass filtering. Next, the AD sampling module separates the flutter noise signal caused by vibration through a Chebyshev type digital bandpass filter.

2. The detector according to claim 1, wherein, The detector also includes a digital spectrometer system, wherein the detector signal conditioning circuit, the adaptive flutter noise suppression system, and the vibration absorber drive circuit are disposed in the digital multichannel analyzer of the digital spectrometer system.

3. The detector according to claim 1, wherein, The detector jitter noise suppression system is also used to stop adjusting the vibration of the vibration absorber when the error signal meets the minimization condition.

4. The detector according to claim 1, wherein, The adaptive noise suppression algorithm is configured to adjust the order and coefficients of the adaptive filter.

5. The detector according to claim 1, wherein, The adaptive flutter noise suppression system is specifically used for: Obtain the current vibration parameters of the vibration absorber; The vibration adjustment parameters are obtained based on the current vibration parameters of the vibration absorber using the adaptive noise suppression algorithm; and Based on the vibration adjustment parameters, the vibration adjustment signal is output.

6. The detector according to claim 5, wherein, The process of obtaining the current vibration parameters of the vibration absorber includes: Obtain the vibration parameters stored locally in the adaptive vibration noise suppression system to obtain the current vibration parameters of the vibration absorber; The adaptive vibration noise suppression system updates the locally stored vibration parameters based on the vibration adjustment parameters in the output vibration adjustment signal after each output of the vibration adjustment signal. Specifically, before the adaptive vibration noise suppression system outputs the vibration adjustment signal for the first time, the locally stored vibration parameters are the initial vibration parameters of the vibration absorber.

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