In Electronic Warfare （EW） receivers, the desired Dynamic Range （DR） often far exceeds the dynamic range attainable with available Analog-to-Digital Converter （ADC） technology. ADC is the key bottleneck in achie...In Electronic Warfare （EW） receivers, the desired Dynamic Range （DR） often far exceeds the dynamic range attainable with available Analog-to-Digital Converter （ADC） technology. ADC is the key bottleneck in achieving the needed dynamic range. In this paper, an approach for improving the effective DR by utiliTing multiple amplifiers is presented. The amplifiers, arranged in parallel channels with different gains, can increase the dynamic range greatly.展开更多
In the future, the Very Large Area gamma-ray Space Telescope is expected to observe high-energy electrons and gamma rays in the MeV to TeV range with unprecedented acceptance. As part of the detector suite, a high-ene...In the future, the Very Large Area gamma-ray Space Telescope is expected to observe high-energy electrons and gamma rays in the MeV to TeV range with unprecedented acceptance. As part of the detector suite, a high-energy imaging calorimeter(HEIC) is currently being developed as a homogeneous calorimeter that utilizes long bismuth germanate(BGO) scintillation crystals as both absorbers and detectors. To accurately measure the energy deposition in the BGO bar of HEIC, a highdynamic-range readout method using a silicon photomultiplier(SiPM) and multiphotodiode(PD) with different active areas has been proposed. A prototype readout system that adopts multichannel charge measurement ASICs was also developed to read out the combined system of SiPMs and PDs. Preliminary tests confirmed the feasibility of the readout scheme, which is expected to have a dynamic range close to 10~6.展开更多
For the optimization of dynamic range and bandwidth of digital intermediate frequency receiver(DIFR), main factors affecting them and their relationships are studied. Firstly, the DIFR sensitivity, bandwidth, noise fa...For the optimization of dynamic range and bandwidth of digital intermediate frequency receiver(DIFR), main factors affecting them and their relationships are studied. Firstly, the DIFR sensitivity, bandwidth, noise factor of radio frequency (RF) analog front-end (RFAF), and processing gain of intermediate frequency(IF) sampling are analyzed. Secondly, the constraint relationship of the noise factor of RFAF, the signal-to-noise ratio of ADC and the dynamic range of DIFR are studied. The relationship between the dynamic range and the RFAF gain, and that of the extended dynamic range and the RF AGC(automatic gain control) step are educed and simulated. These results can be used as theory foundations and design references for the implementation and optimization of the large dynamic range and wideband DIFR.展开更多
Radio Frequency (RF) switch circuit is the basic part of microwave devices and systems. The non-linearity distortion figure is necessary in the field of large dynamic range of signal. This letter analyzes the basic sw...Radio Frequency (RF) switch circuit is the basic part of microwave devices and systems. The non-linearity distortion figure is necessary in the field of large dynamic range of signal. This letter analyzes the basic switch circuit and its inter-modulation, and studies in detail the measurement methods and systems of RF switch intercept point. It has provided cascaded simulation testing methods, which can accurately measure the PF switch, of which the second or third order intercept point value is above 75dB and 60dB, respectively. As the testing results are consistent with the theoretical analyses, it proves that the validity of the method satisfies the requirements of large scaled linearity measurement in engineering.展开更多
The Shack-Hartmann wavefront sensor(SHWS)is widely used for high-speed,precise,and stable wavefront measurements.However,conventional SHWSs encounter a limitation in that the focused spot from each microlens is restri...The Shack-Hartmann wavefront sensor(SHWS)is widely used for high-speed,precise,and stable wavefront measurements.However,conventional SHWSs encounter a limitation in that the focused spot from each microlens is restricted to a single microlens,leading to a limited dynamic range.Herein,we propose an adaptive spot matching(ASM)-based SHWS to extend the dynamic range.This approach involves seeking an incident wavefront that best matches the detected spot distribution by employing a Hausdorff-distance-based nearest-distance matching strategy.The ASM-SHWS enables comprehensive spot matching across the entire imaging plane without requiring initial spot correspondences.Furthermore,due to its global matching capability,ASM-SHWS can maintain its capacity even if a portion of the spots are missing.Experiments showed that the ASM-SHWS could measure a high-curvature spherical wavefront with a local slope of 204.97 mrad,despite a 12.5%absence of spots.This value exceeds that of the conventional SHWS by a factor of 14.81.展开更多
China plans to develop the next generation dark matter particle explorer satellite,referred to as the Very Large Area Space Telescope(VLAST).As an essential step in this process,the prototype design of detectors and e...China plans to develop the next generation dark matter particle explorer satellite,referred to as the Very Large Area Space Telescope(VLAST).As an essential step in this process,the prototype design of detectors and electronics for the VLAST is currently underway.The nuclide detector is a core detector in the VLAST.It mainly measures nuclides’charges and distinguishes high-energy gamma rays and electrons.This paper will discuss the prototype readout electronics for the VLAST’s nuclide detector,which accurately measures the charge signal of the photomultiplier tubes using the VATA160 applicationspecific integrated circuit chip;furthermore,we consider a series of critical problems,including radiation-hardening and environment monitoring.The test results show that the system exhibits stable operation,good performance,and good technical indicators.Furthermore,each electronic channel achieves a dynamic range of 0-12.5 pC,the random noise level exceeds 1.6 fC,and the integral nonlinearity exceeds 0.35%.展开更多
针对目前常用的基于参数化非线性模型(Parameterized Nonlinear Model,PNM)的补偿算法存在易陷入局部最小值,导致补偿性能不稳的问题,该文提出了基于最小二乘支持向量机(Least Squares Support Vector Machine,LS-SVM)的宽带接收前端非...针对目前常用的基于参数化非线性模型(Parameterized Nonlinear Model,PNM)的补偿算法存在易陷入局部最小值,导致补偿性能不稳的问题,该文提出了基于最小二乘支持向量机(Least Squares Support Vector Machine,LS-SVM)的宽带接收前端非线性补偿算法.该算法基于减谱-时频变换法(Spectrum Reduction Algorithm based on Time-Frequency Conversion,SRA-TFC)盲分离接收前端输出信号中的大功率基波信号和其他小功率信号,并以此作为LS-SVM逆模型的训练输入-输出样本对.引入最小二乘支持向量回归(Least Squares Support Vector Regression,LS-SVR)算法高精度拟合接收前端非线性逆模型.通过以宽带接收前端的输出信号为测试样本消除其非线性失真分量.仿真与实测结果表明:该算法可使宽带接收前端的无杂散失真动态范围(Spurs-Free-Dynamic-Range,SFDR)提高约20 dB,较基于PNM的补偿算法提高了约5 dB.展开更多
在大动态范围的复杂通信系统中,自动增益控制系统的性能起着至关重要的作用。针对传统自动增益控制系统的动态范围较小及收敛速度较慢的问题,提出了一种大动态范围数字AGC快速控制算法。该算法采用射频峰值检测以及大信号指示的方式实...在大动态范围的复杂通信系统中,自动增益控制系统的性能起着至关重要的作用。针对传统自动增益控制系统的动态范围较小及收敛速度较慢的问题,提出了一种大动态范围数字AGC快速控制算法。该算法采用射频峰值检测以及大信号指示的方式实现对射频功率的快速检测;采用平均功率的方式对中频信号功率进行滑动平均,准确获取中频信号的平均功率;结合中频和射频增益控制策略,对接收信道的增益进行分配以及快速控制,使得射频信号经过射频单元后始终位于模数转换器(Analog to Digital Converter,ADC)的动态范围内,从而实现射频信号的稳定接收。仿真结果表明,相较于传统算法,所提算法的收敛时间由毫秒级提高到了微秒级,动态范围大幅提升。展开更多
文摘In Electronic Warfare （EW） receivers, the desired Dynamic Range （DR） often far exceeds the dynamic range attainable with available Analog-to-Digital Converter （ADC） technology. ADC is the key bottleneck in achieving the needed dynamic range. In this paper, an approach for improving the effective DR by utiliTing multiple amplifiers is presented. The amplifiers, arranged in parallel channels with different gains, can increase the dynamic range greatly.
基金Foundation of China (Nos. 12227805, U1831206, 12103095, 12235012, 12273120, and 11973097)the Scientific Instrument Developing Project of the Chinese Academy of Sciences (No. GJJSTD20210009)。
文摘In the future, the Very Large Area gamma-ray Space Telescope is expected to observe high-energy electrons and gamma rays in the MeV to TeV range with unprecedented acceptance. As part of the detector suite, a high-energy imaging calorimeter(HEIC) is currently being developed as a homogeneous calorimeter that utilizes long bismuth germanate(BGO) scintillation crystals as both absorbers and detectors. To accurately measure the energy deposition in the BGO bar of HEIC, a highdynamic-range readout method using a silicon photomultiplier(SiPM) and multiphotodiode(PD) with different active areas has been proposed. A prototype readout system that adopts multichannel charge measurement ASICs was also developed to read out the combined system of SiPMs and PDs. Preliminary tests confirmed the feasibility of the readout scheme, which is expected to have a dynamic range close to 10~6.
文摘For the optimization of dynamic range and bandwidth of digital intermediate frequency receiver(DIFR), main factors affecting them and their relationships are studied. Firstly, the DIFR sensitivity, bandwidth, noise factor of radio frequency (RF) analog front-end (RFAF), and processing gain of intermediate frequency(IF) sampling are analyzed. Secondly, the constraint relationship of the noise factor of RFAF, the signal-to-noise ratio of ADC and the dynamic range of DIFR are studied. The relationship between the dynamic range and the RFAF gain, and that of the extended dynamic range and the RF AGC(automatic gain control) step are educed and simulated. These results can be used as theory foundations and design references for the implementation and optimization of the large dynamic range and wideband DIFR.
文摘Radio Frequency (RF) switch circuit is the basic part of microwave devices and systems. The non-linearity distortion figure is necessary in the field of large dynamic range of signal. This letter analyzes the basic switch circuit and its inter-modulation, and studies in detail the measurement methods and systems of RF switch intercept point. It has provided cascaded simulation testing methods, which can accurately measure the PF switch, of which the second or third order intercept point value is above 75dB and 60dB, respectively. As the testing results are consistent with the theoretical analyses, it proves that the validity of the method satisfies the requirements of large scaled linearity measurement in engineering.
基金supported by the Fundamental Research Funds for the Central Universities of Shanghai Jiao Tong University and the Shanghai Jiao Tong University 2030 Initiative(No.WH510363001-10)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(No.SL2022ZD205)+1 种基金the Science Foundation of the Donghai Laboratory(No.DH-2022KF01001)National Natural Science Foundation of China(No.62205189).
文摘The Shack-Hartmann wavefront sensor(SHWS)is widely used for high-speed,precise,and stable wavefront measurements.However,conventional SHWSs encounter a limitation in that the focused spot from each microlens is restricted to a single microlens,leading to a limited dynamic range.Herein,we propose an adaptive spot matching(ASM)-based SHWS to extend the dynamic range.This approach involves seeking an incident wavefront that best matches the detected spot distribution by employing a Hausdorff-distance-based nearest-distance matching strategy.The ASM-SHWS enables comprehensive spot matching across the entire imaging plane without requiring initial spot correspondences.Furthermore,due to its global matching capability,ASM-SHWS can maintain its capacity even if a portion of the spots are missing.Experiments showed that the ASM-SHWS could measure a high-curvature spherical wavefront with a local slope of 204.97 mrad,despite a 12.5%absence of spots.This value exceeds that of the conventional SHWS by a factor of 14.81.
基金supported by the National Natural Science Foundation of China(Nos.U2031206,U1831206,11975292,11875304)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(No.GJJSTD20210009)+1 种基金the CAS“Light of West China”Programthe CAS Pioneer Hundred Talent Program。
文摘China plans to develop the next generation dark matter particle explorer satellite,referred to as the Very Large Area Space Telescope(VLAST).As an essential step in this process,the prototype design of detectors and electronics for the VLAST is currently underway.The nuclide detector is a core detector in the VLAST.It mainly measures nuclides’charges and distinguishes high-energy gamma rays and electrons.This paper will discuss the prototype readout electronics for the VLAST’s nuclide detector,which accurately measures the charge signal of the photomultiplier tubes using the VATA160 applicationspecific integrated circuit chip;furthermore,we consider a series of critical problems,including radiation-hardening and environment monitoring.The test results show that the system exhibits stable operation,good performance,and good technical indicators.Furthermore,each electronic channel achieves a dynamic range of 0-12.5 pC,the random noise level exceeds 1.6 fC,and the integral nonlinearity exceeds 0.35%.
文摘针对目前常用的基于参数化非线性模型(Parameterized Nonlinear Model,PNM)的补偿算法存在易陷入局部最小值,导致补偿性能不稳的问题,该文提出了基于最小二乘支持向量机(Least Squares Support Vector Machine,LS-SVM)的宽带接收前端非线性补偿算法.该算法基于减谱-时频变换法(Spectrum Reduction Algorithm based on Time-Frequency Conversion,SRA-TFC)盲分离接收前端输出信号中的大功率基波信号和其他小功率信号,并以此作为LS-SVM逆模型的训练输入-输出样本对.引入最小二乘支持向量回归(Least Squares Support Vector Regression,LS-SVR)算法高精度拟合接收前端非线性逆模型.通过以宽带接收前端的输出信号为测试样本消除其非线性失真分量.仿真与实测结果表明:该算法可使宽带接收前端的无杂散失真动态范围(Spurs-Free-Dynamic-Range,SFDR)提高约20 dB,较基于PNM的补偿算法提高了约5 dB.
文摘在大动态范围的复杂通信系统中,自动增益控制系统的性能起着至关重要的作用。针对传统自动增益控制系统的动态范围较小及收敛速度较慢的问题,提出了一种大动态范围数字AGC快速控制算法。该算法采用射频峰值检测以及大信号指示的方式实现对射频功率的快速检测;采用平均功率的方式对中频信号功率进行滑动平均,准确获取中频信号的平均功率;结合中频和射频增益控制策略,对接收信道的增益进行分配以及快速控制,使得射频信号经过射频单元后始终位于模数转换器(Analog to Digital Converter,ADC)的动态范围内,从而实现射频信号的稳定接收。仿真结果表明,相较于传统算法,所提算法的收敛时间由毫秒级提高到了微秒级,动态范围大幅提升。
