A multifunctional signal processing device for nuclear measurement

Abstract

The present application relates to the technical field of nuclear radiation monitoring, and provides a multifunctional signal processing device for nuclear measurement, which comprises three signal conditioning modules for conditioning signals of three kinds of nuclear measurement detectors, and the weak signals output by the three signal conditioning modules are shielded through three coaxial cables and connectors, then enter corresponding channels for amplification, filtering, gain adjustment, signal conditioning and isolation output, the signal processing device further comprises a signal processing module, which uses a high-speed ADC and a counter to sample and count the conditioned signals to form digital signals.The multifunctional signal processing device for nuclear measurement is used for processing output signals of various detectors in a nuclear measurement system, can digitize weak pulse signals, weak current signals and charge pulses accumulated and overlapped, and is simple and efficient.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nuclear radiation monitoring, in particular to a multifunctional signal processing device for nuclear measurement. BACKGROUND

[0002] A nuclear measurement system generally comprises a nuclear radiation detector and a nuclear electronics measurement system. The signal processing part in the nuclear electronics measurement system receives various analog signals from the nuclear radiation detector, and through amplification, shaping, sampling and other processing, converts them into digital signals that are easy to identify. The function, performance and reliability of the signal processing device will greatly affect the safety and reliability of the nuclear measurement system.

[0003] In a nuclear measurement system, nuclear radiation detectors mainly include counting tube type detectors, fission ionization chamber type detectors and boron-coated ionization chamber type detectors. Different detectors will output weak charge pulses, weak currents, and accumulated overlapping charge pulses under different working conditions. This requires a signal processing device that can process different types of analog signals to meet the detection of multiple channel nuclear measurement signals and obtain effective nuclear information.

[0004] At present, common signal processing devices for nuclear measurement can only process signals from one type of nuclear radiation detector, and the front end needs to be connected to a preamplifier, which has the following disadvantages or deficiencies: the measurement function of various signal processing devices is relatively single, and multiple signal processing devices need to be equipped to complete the signal processing requirements of the entire nuclear measurement system, increasing the use cost and system failure rate; the front end of the signal processing device needs to be connected to a preamplifier, increasing the use of cables and connectors, affecting the reliability of the system. SUMMARY

[0005] In order to overcome the shortcomings or deficiencies of the prior art, the present application provides a multifunctional signal processing device for nuclear measurement, which is used for processing signals output by various detectors in a nuclear measurement system, can digitize weak pulse signals, weak current signals and accumulated overlapping charge pulses, and is simple and efficient.

[0006] In order to achieve the above object, the technical solution of the present application is as follows: a multifunctional signal processing device for nuclear measurement, which carries out digital processing on analog signals output by nuclear measurement counter tube type detectors, fission ionization chamber type detectors and boron-coated ionization chamber type detectors, and displays the processed signals; the signal processing device comprises three signal conditioning modules for signal conditioning of the three types of nuclear measurement detectors, and the weak signals output by the modules are shielded through three coaxial cables and connectors, then enter corresponding channels for amplification, filtering, gain adjustment, signal conditioning and isolation output; the signal processing device further comprises a signal processing module which samples and counts the conditioned signals using a high-speed ADC and a counter to form digital signals.

[0007] In the above technical solution, the signal processing device comprises one base plate, one test interface module, one signal processing module, one information display module, one state indication module, one low-voltage power supply module, one AC IN module, one communication I / O module, one switching value I / O module, one analog I / O module and one signal conditioning module; the test interface module, the signal processing module, the information display module, the state indication module and the low-voltage power supply module are installed at the front part of the base plate through a 96-core connector, the AC IN module, the communication module, the switching value module, the analog I / O module and the signal conditioning module are installed at the rear part of the base plate through a 96-core connector, and the signal conditioning module is replaced according to the type of the actually used detector, including a counter tube type detector signal conditioning module, a fission ionization chamber type detector signal conditioning module and a boron-coated ionization chamber type detector signal conditioning module.

[0008] The multifunctional signal processing device for nuclear measurement is convenient to use, does not need to be connected with other components, can be applied to processing of output signals of various detectors of a nuclear measurement system, can simultaneously carry out digital processing on weak pulse signals, weak current signals and charge pulses stacked and overlapped, and can solve the problems of single function of existing signal processing devices, the need to equip multiple signal processing devices and the need to connect a preamplifier at the front end. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 It is a front panel schematic diagram of the signal processing device.

[0010] Figure 2 It is a rear panel schematic diagram of the signal processing device.

[0011] Figure 3 It is a circuit principle diagram of the counter tube type detector signal conditioning module in the present application.

[0012] Figure 4 It is a circuit principle diagram of the fission ionization chamber type detector signal conditioning module in the present application.

[0013] Figure 5 This is a circuit diagram of the signal conditioning module for the boron-coated ionization chamber detector in this invention.

[0014] Figure 6 This is a circuit schematic diagram of the signal processing module in this invention. Detailed Implementation

[0015] The embodiments of the present invention will be further described below with reference to the accompanying drawings and specific examples.

[0016] like Figure 1 , Figure 2 As shown, this embodiment of the invention provides a multifunctional nuclear measurement signal processing device, which consists of a base plate, a test interface module, a signal processing module, an information display module, a status indicator module, a low-voltage power supply module, an AC IN module, a communication I / O module, a digital I / O module, an analog I / O module, and a signal conditioning module.

[0017] The test interface module, signal processing module, information display module, status indication module, and low-voltage power supply module are mounted on the front of the base plate via a 96-pin connector. For example... Figure 1 As shown.

[0018] The AC IN module, communication module, digital I / O module, analog I / O module, and signal conditioning module are mounted on the rear of the base plate via a 96-pin connector, such as... Figure 2 As shown.

[0019] Except for the signal conditioning module, all other modules are general-purpose modules. The signal conditioning module is replaced according to the actual type of detector used, including signal conditioning modules for counter tube type detectors, fission ionization chamber type detectors, and boron-coated ionization chamber type detectors.

[0020] Figure 3 The circuit schematic of the signal conditioning module for a tube counter detector is given. This module mainly consists of five parts: a high-voltage generation and filtering circuit, an integrating amplifier / second-stage amplifier / third-stage amplifier, a signal conditioning circuit, a DAC circuit, and an ADC circuit, as detailed below:

[0021] The high-voltage generation and filtering circuit is mainly used to generate high voltage and filter interference signals in the high-voltage power supply. The filtered high voltage is then provided to the detector.

[0022] The high voltage power supply module of the counter tube is composed of a high voltage module (0V-1500V) and corresponding high voltage control, high voltage sampling and high voltage regulating circuits. The high voltage module is connected to a relay which is controlled by the signal processing module. The signal processing module detects the "source range detector high voltage power off" signal and the "automatic source range detector high voltage power off" signal, and controls the corresponding high voltage off relay to act after logical "or" operation. When the "source range detector high voltage power off" signal and the "automatic source range detector high voltage power off" signal disappear at the same time, the corresponding relay is controlled to restore the high voltage module power supply.

[0023] The integral amplification / secondary amplification / tertiary amplification is a tertiary amplifier for amplifying weak pulse signals from the boron-coated proportional counter tube.

[0024] The signal conditioning circuit mainly discriminates, filters, shapes and drives the amplified signals, and outputs voltage pulses with different frequencies, a pulse width less than 1us and an amplitude greater than 1V.

[0025] The DAC circuit controls the high voltage module and the discrimination level generation circuit to output corresponding voltages according to the high voltage set value and the discrimination threshold set value given by the signal processing module.

[0026] The ADC circuit samples the high voltage, the discrimination level and the ±12V voltage, and transmits them to the signal processing module for calculation.

[0027] Figure 4 A circuit principle diagram of a signal conditioning module of a fission ionization chamber type detector is given. The module mainly consists of seven parts, i.e. a high voltage generation and filtering circuit, an integral amplification / secondary amplification / tertiary amplification, a signal conditioning circuit, an MSV filtering circuit, an MSV processing circuit, a DAC circuit and an ADC circuit, which are as follows:

[0028] The high voltage generation and filtering circuit is mainly used for generating high voltage and filtering interference signals in the high voltage power supply, and the filtered high voltage is provided to the detector.

[0029] The high voltage power supply module of the fission ionization chamber is composed of a high voltage module (0V-1500V) and corresponding high voltage control, high voltage sampling and high voltage regulating circuits. The high voltage module is connected to a relay which is controlled by the signal processing module.

[0030] The integral amplification / secondary amplification / tertiary amplification is a tertiary amplifier for amplifying weak pulse signals from the fission ionization chamber detector.

[0031] The signal conditioning circuit mainly discriminates, filters, shapes and drives the amplified signals, and outputs voltage pulses with different frequencies, a pulse width less than 1us and an amplitude greater than 1V.

[0032] The DAC circuit controls the high voltage module and the discrimination level generation circuit to output corresponding voltages according to the high voltage setting value and the discrimination threshold setting value given by the signal processing module.

[0033] The MSV filter circuit is a band-pass filter, which processes the stacked pulse signal to extract effective pulses and sends them to the MSV processing module.

[0034] The MSV processing module converts the filtered stacked pulse into a mean square voltage, which is transmitted to the signal processing module after being sampled by the ADC.

[0035] The ADC circuit samples the high voltage, the discrimination level, and the ±12V voltage and transmits them to the signal processing module for calculation.

[0036] Figure 5 The circuit principle diagram of the signal conditioning module of the boron-coated ionization chamber type detector is given, which mainly consists of five parts, namely, a high voltage generation filter circuit, a current I-V conversion circuit, a signal conditioning circuit, a DAC circuit, and an ADC circuit, as follows:

[0037] The high voltage generation filter circuit is mainly used to generate high voltage and filter interference signals in the high voltage power supply, and the filtered high voltage is provided to the detector.

[0038] The high voltage power supply module is composed of an external high voltage module (0V-1500V) and corresponding high voltage control, high voltage sampling, and high voltage regulation circuits. The high voltage module is connected to a relay, which is controlled by the signal processing module.

[0039] The current I-V conversion circuit is used to amplify the weak current signal from the boron-coated ionization chamber and perform I-V conversion.

[0040] The signal conditioning circuit mainly filters the voltage value after I-V conversion.

[0041] The DAC circuit controls the high voltage module to output corresponding voltages according to the high voltage setting value given by the signal processing module.

[0042] The ADC circuit samples the filtered I-V voltage value, high voltage, and ±12V voltage and transmits them to the signal processing module for calculation.

[0043] Figure 6The signal processing module circuit schematic diagram is given. The signal processing module takes a TI ARM processor RM48L952 as the core. All functions (including pulse counting, data processing, indicator light control, relay output control, RS232 communication, 4-20mA output control, etc.) except data display are controlled and processed by the processor. The main frequency of RM48L952 can reach 220MHz, and the internal RAM capacity is 256K.

[0044] The main functions of the ARM processor on-chip peripherals are as follows:

[0045] 1) The internal UART1 is connected to the test interface module RS232 transceiver (non-isolated type) through the backplane, which is used for device parameter setting and reading;

[0046] 2) The internal ADC is used for monitoring the low-voltage power module digital +5V power voltage;

[0047] 3) The internal SPI1 is connected to the signal conditioning module ADC (used for high-voltage, ±12V, discrimination threshold monitoring) and DAC (used for adjusting high-voltage output value and discrimination threshold output value) through the backplane;

[0048] 4) The internal SPI3 is connected to the analog I / O module DAC through the backplane, which is used for controlling 4-20mA analog output;

[0049] 5) The internal SPI5 is connected to the non-volatile memory, which is used for storing device parameters;

[0050] 6) The internal Edge module is used for collecting the pulse count output by the signal conditioning module;

[0051] 7) The internal ADC module is used for collecting the MSV voltage output of the preamplifier;

[0052] 8) The internal GIO is used for controlling the on-off input and output of the on-off I / O module, the high-voltage switch of the signal conditioning module, the indicator light of the status indication module, etc.;

[0053] 9) The internal CAN module is connected to the CAN transceiver of the information display module through the backplane, which is used for sending measurement data to the information display module.

[0054] The contents not described in detail in the specification belong to the prior art known to those skilled in the art.

[0055] The above only describes the embodiments of the present application, and does not limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A multi-functional nuclear measurement signal processing device, characterized by: The signal processing device carries out digital processing on analog signals output by nuclear measurement counter tube type detectors, fission ionization chamber type detectors and boron-coated ionization chamber type detectors, and displays the processed signals; the signal processing device comprises three signal conditioning modules, which are respectively used for signal conditioning of the three types of nuclear measurement detectors, and the weak signals output by the three types of nuclear measurement detectors are shielded through three coaxial cables and connectors and then input into corresponding channels for amplification, filtering, gain adjustment, signal conditioning and then isolated output; the signal processing device further comprises a signal processing module, which uses a high-speed ADC and a counter to sample and count the conditioned signals to form digital signals; the signal processing device comprises one base plate, one test interface module, one signal processing module, one information display module, one state indication module, one low-voltage power supply module, one AC IN module, one communication I / O module, one switching value I / O module, one analog value I / O module and one signal conditioning module, wherein the test interface module, the signal processing module, the information display module, the state indication module and the low-voltage power supply module are installed at the front part of the base plate through a 96-core connector, the AC IN module, the communication module, the switching value module, the analog value I / O module and the signal conditioning module are installed at the rear part of the base plate through a 96-core connector, and the signal conditioning module is replaced according to the type of the actually used detector, including a counter tube type detector signal conditioning module, a fission ionization chamber type detector signal conditioning module and a boron-coated ionization chamber type detector signal conditioning module.

2. The multi-functional nuclear measurement signal processing apparatus according to claim 1, characterized by: The counter tube type detector signal conditioning module is composed of five parts, namely a high-voltage generation filtering circuit, an integral amplification / two-stage amplification / three-stage amplification, a signal conditioning circuit, a DAC circuit and an ADC circuit, and specifically as follows: The high-voltage generation filtering circuit is used for generating high voltage and filtering interference signals in the high-voltage power supply, and the filtered high voltage is provided to the detector; The counter tube high-voltage power supply module is composed of a high-voltage module and corresponding high-voltage control, high-voltage sampling and high-voltage adjustment circuits, the high-voltage module is connected to a relay, the relay is controlled by the signal processing module, the signal processing module detects "off-source range detector high-voltage power supply" signals and "automatic off-source range detector high-voltage power supply" signals, and controls the corresponding high-voltage off relay to act after logical "or" operation, and when the "off-source range detector high-voltage power supply" signals and the "automatic off-source range detector high-voltage power supply" signals disappear at the same time, the corresponding relay is controlled to restore the high-voltage module power supply; The integral amplification / two-stage amplification / three-stage amplification is a three-stage amplifier, which is used for amplifying weak pulse signals from the boron-coated proportional counter tube; The signal conditioning circuit is used for discriminating, filtering and shaping the amplified signals, and driving and outputting voltage pulses with different frequencies, a pulse width less than 1us and an amplitude greater than 1V; The DAC circuit controls the high-voltage module and the discrimination level generation circuit to output corresponding voltages according to the high-voltage set value and the discrimination threshold set value given by the signal processing module; The ADC circuit samples high voltage division, discrimination level and ±12V voltage and transmits to the signal processing module for calculation.

3. The multi-functional nuclear measurement signal processing apparatus according to claim 1, characterized by: The signal conditioning module of the fission ionization chamber type detector is composed of seven parts, namely, a high voltage generation filter circuit, an integral amplifier / secondary amplifier / tertiary amplifier, a signal conditioning circuit, an MSV filter circuit, an MSV processing circuit, a DAC circuit and an ADC circuit, and specifically as follows: The high voltage generation filter circuit is used for generating high voltage and filtering interference signals in the high voltage power supply, and the filtered high voltage is provided to the detector; The high voltage power supply module of the fission ionization chamber is composed of a high voltage module and corresponding high voltage control, high voltage sampling and high voltage regulation circuits, and the high voltage module is connected to a relay controlled by the signal processing module; The integral amplifier / secondary amplifier / tertiary amplifier is a tertiary amplifier for amplifying weak pulse signals from the fission ionization chamber detector; The signal conditioning circuit is used for discriminating, filtering and shaping the amplified signals and driving the output voltage pulse with a pulse width less than 1us and an amplitude greater than 1V at different frequencies; The DAC circuit controls the high voltage module and the discrimination level generation circuit to output corresponding voltages according to the high voltage set value and the discrimination threshold set value given by the signal processing module; The MSV filter circuit is a band-pass filter for processing stacked pulse signals to extract effective pulses and send them to the MSV processing module; The MSV processing module converts the filtered stacked pulses into mean square voltage, which is transmitted to the signal processing module after ADC sampling; The ADC circuit samples high voltage division, discrimination level and ±12V voltage and transmits to the signal processing module for calculation.

4. The multi-functional nuclear measurement signal processing apparatus according to claim 1, characterized by: The signal conditioning module of the boron-coated ionization chamber type detector is composed of five parts, namely, a high voltage generation filter circuit, a current I-V conversion circuit, a signal conditioning circuit, a DAC circuit and an ADC circuit, and specifically as follows: The high voltage generation filter circuit is used for generating high voltage and filtering interference signals in the high voltage power supply, and the filtered high voltage is provided to the detector; The high voltage power supply module is composed of a high voltage module and corresponding high voltage control, high voltage sampling and high voltage regulation circuits, and the high voltage module is connected to a relay controlled by the signal processing module; The current I-V conversion circuit is used for amplifying weak current signals from the boron-coated ionization chamber and performing I-V conversion; The signal conditioning circuit is used for filtering the voltage value after I-V conversion; The DAC circuit controls the high voltage module to output corresponding voltages according to the high voltage set value given by the signal processing module; The ADC circuit samples the filtered I-V voltage value, high voltage division and ±12V voltage and transmits to the signal processing module for calculation.

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