A correlation-based digital background calibration algorithm for pipelined Analog-to- Digital Converters (ADCs) is presented in this paper. The merit of the calibration algorithm is that the main errors information, w...A correlation-based digital background calibration algorithm for pipelined Analog-to- Digital Converters (ADCs) is presented in this paper. The merit of the calibration algorithm is that the main errors information, which include the capacitor mismatches and residue amplifier distortion, are extracted integrally. A modified 1st pipelined stage is adopted to solve the signal overflow caused by the Pseudo-random Noise (PN) sequences. Behavioral simulation results verify the effectiveness of the algorithm. It improves the Signal-to-Noise-plus-Distortion Ratio (SNDR) and Spurious-Free-Dynamic-Range (SFDR) of the pipelined ADC from 41.8 dB to 78.3 dB and 55.6 dB to 98.6 dB, respectively, which is comparable to the prior arts.展开更多
设计一种用于高速高精度流水线ADC的流水线ADC子级电路,采用伪随机序列控制子ADC电路中比较器阵列的参考比较电压。比较器的高低位被随机分配,消除某个比较器的固有失调对子ADC量化的影响,温度计码的伪随机性可以消除MDAC电容的失配误...设计一种用于高速高精度流水线ADC的流水线ADC子级电路,采用伪随机序列控制子ADC电路中比较器阵列的参考比较电压。比较器的高低位被随机分配,消除某个比较器的固有失调对子ADC量化的影响,温度计码的伪随机性可以消除MDAC电容的失配误差对余量输出的影响。电路采用0.18μm 1P5M 1.8 V CMOS工艺,运用于12 bit 250 Msample/s流水线ADC电路中,实际测得流水线ADC电路的SNR为69.92 dB,SFDR为81.17 dB。展开更多
针对现有编码调制的典型多输入-多输出天波超视距雷达(MIMO-OTHR)波形实际上不严格正交,仅仅依靠降低波形间互相关性来提高波形准正交性能的情况,提出一种改进的基于Walsh矩阵的慢时间随机相位编码(Slow Time Random Phase-Coded,STRPC...针对现有编码调制的典型多输入-多输出天波超视距雷达(MIMO-OTHR)波形实际上不严格正交,仅仅依靠降低波形间互相关性来提高波形准正交性能的情况,提出一种改进的基于Walsh矩阵的慢时间随机相位编码(Slow Time Random Phase-Coded,STRPC)波形,以提高编码波形的正交性能,进而提高雷达系统的目标检测能力;同时,为解决Walsh矩阵编码的STRPC波形自相关性能不够好的问题,采用MIMO-OTHR失配滤波方法,以一定的失配滤波损失,进一步改善脉压主副瓣比.理论分析与仿真结果验证了Walsh矩阵编码对改善STRPC波形正交性的有效性.展开更多
Deviation of threshold voltage and effective mobility due to random dopant fluctuation is proposed.An improved 65 nm average drain current MOS model calledαlaw is utilized after fitting HSPICE simulating data and ext...Deviation of threshold voltage and effective mobility due to random dopant fluctuation is proposed.An improved 65 nm average drain current MOS model calledαlaw is utilized after fitting HSPICE simulating data and extracting process parameters.Then,a current mismatch model of nanoscale MOSFETs induced by random dopant fluctuation is presented based on propagation of variation theory.In test conditions,the calculated standard deviation applying this model,compared to 100 times Monte-Carlo simulation data with HSPICE,indicates that the average relative error and relative standard deviation is 0.24%and 0.22%,respectively.The results show that this mismatch model is effective to illustrate the physical mechanism,as well as being simple and accurate.展开更多
基金Supported by the Doctoral Program Foundation of Institutions of Higher Education of China (No.20120111120008)State Key Lab of ASIC & System(Fudan University) (No. 11KF001)Special Fund for Doctoral Program (Hefei University of Technology) (No.2011HGBZ0953)
文摘A correlation-based digital background calibration algorithm for pipelined Analog-to- Digital Converters (ADCs) is presented in this paper. The merit of the calibration algorithm is that the main errors information, which include the capacitor mismatches and residue amplifier distortion, are extracted integrally. A modified 1st pipelined stage is adopted to solve the signal overflow caused by the Pseudo-random Noise (PN) sequences. Behavioral simulation results verify the effectiveness of the algorithm. It improves the Signal-to-Noise-plus-Distortion Ratio (SNDR) and Spurious-Free-Dynamic-Range (SFDR) of the pipelined ADC from 41.8 dB to 78.3 dB and 55.6 dB to 98.6 dB, respectively, which is comparable to the prior arts.
文摘设计一种用于高速高精度流水线ADC的流水线ADC子级电路,采用伪随机序列控制子ADC电路中比较器阵列的参考比较电压。比较器的高低位被随机分配,消除某个比较器的固有失调对子ADC量化的影响,温度计码的伪随机性可以消除MDAC电容的失配误差对余量输出的影响。电路采用0.18μm 1P5M 1.8 V CMOS工艺,运用于12 bit 250 Msample/s流水线ADC电路中,实际测得流水线ADC电路的SNR为69.92 dB,SFDR为81.17 dB。
文摘针对现有编码调制的典型多输入-多输出天波超视距雷达(MIMO-OTHR)波形实际上不严格正交,仅仅依靠降低波形间互相关性来提高波形准正交性能的情况,提出一种改进的基于Walsh矩阵的慢时间随机相位编码(Slow Time Random Phase-Coded,STRPC)波形,以提高编码波形的正交性能,进而提高雷达系统的目标检测能力;同时,为解决Walsh矩阵编码的STRPC波形自相关性能不够好的问题,采用MIMO-OTHR失配滤波方法,以一定的失配滤波损失,进一步改善脉压主副瓣比.理论分析与仿真结果验证了Walsh矩阵编码对改善STRPC波形正交性的有效性.
文摘Deviation of threshold voltage and effective mobility due to random dopant fluctuation is proposed.An improved 65 nm average drain current MOS model calledαlaw is utilized after fitting HSPICE simulating data and extracting process parameters.Then,a current mismatch model of nanoscale MOSFETs induced by random dopant fluctuation is presented based on propagation of variation theory.In test conditions,the calculated standard deviation applying this model,compared to 100 times Monte-Carlo simulation data with HSPICE,indicates that the average relative error and relative standard deviation is 0.24%and 0.22%,respectively.The results show that this mismatch model is effective to illustrate the physical mechanism,as well as being simple and accurate.
