A program of adaptive quadrature demodulation is proposed to supply the gaps in the traditional analog detection technology of a silicon micro-machined gyroscope (SMG). This program is suitable for digital phase locke...A program of adaptive quadrature demodulation is proposed to supply the gaps in the traditional analog detection technology of a silicon micro-machined gyroscope (SMG). This program is suitable for digital phase locked loop (DPLL) drive technology that proposed in other papers. In addition the program adopts an adaptive filtering algorithm, which selects the in-phase and quadrature components that are outputs of the DPLL of the SMG's drive mode as reference signals to update the amplitude of the in-phase and quadrature components of the input signal by iteratively. An objective of the program is to minimize the mean square error of the accurate amplitudes and the estimated amplitudes of SMG's detection mode. The simulation and test results prove the feasibility of the program that lays the foundation for the further improvement of the SMG's system performance and the implementation of the SMG system's self-calibration and self-demarcation in future.展开更多
This paper presents the design of a low power （LP） and a low noise figure （NF） quadrature demodula- tor with an on-chip frequency divider for quadrature local oscillator （LO） signal generation. The transconducta...This paper presents the design of a low power （LP） and a low noise figure （NF） quadrature demodula- tor with an on-chip frequency divider for quadrature local oscillator （LO） signal generation. The transconductance stage of the mixer is implemented by an AC-coupled self-bias current reuse topology. On-chip series inductors are employed at the gate terminals of the differential input transconductance stage to improve the voltage gain by enhancing the effective transconductance. The chip is implemented in 65-nm LP CMOS technology. The demod- ulator is designed for an input radio frequency （RF） band ranging from 10.25 to 13.75 GHz. A fixed LO frequency of 12 GHz down-converts the RF band to an intermediate frequency （IF） band ranging from DC to 1.75 GHz. From 10 MHz to 1.75 GHz the demodulator achieves a voltage conversion gain （VCG） ranging from 14.2 to 13.2 dB, and a minimum single-sideband N F （SSB-NF） of 9 dB. The measured third-order input intercept point （lIP3） is -3.3 dBm lbr a two-tone test frequency spacing of 1 MHz. The mixer alone draws a current of only 2.5 mA, whereas the complete demodulator draws a current of 7.18 mA from a 1.2 V supply. The measurement results for a frequency divider, which was fabricated individually, prior to being integrated with the quadrature demodulator, in 65-rim LP CMOS technology, are also presented in this paper.展开更多
Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency(RF) signal.In quadrature demodulation,RF signal is multiplied with the sine ...Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency(RF) signal.In quadrature demodulation,RF signal is multiplied with the sine and cosine wave reference signal and then low-pass filtered to produce the base-band complex signal,which has high computational complexity.In this paper,we propose an efficient quadrature demodulation method for B-mode and color flow imaging,in which the RF signal is demodulated by a pair of finite impulse response filters without mixing with the reference signal,to reduce the computational complexity.The proposed method was evaluated with simulation and in vivo experiments.From the simulation results,the proposed quadrature demodulation method produced similar normalized residual sum of squares(NRSS) and velocity profile compared with the conventional quadrature demodulation method.In the in vivo color flow imaging experiments,the time of the demodulation process was 5.66 ms and 3.36 ms,for the conventional method and the proposed method,respectively.These results indicated that the proposed method can maintain the performance of quadrature demodulation while reducing computational complexity.展开更多
UM2000 signal is a type of multi-audio frequency-modulated signal which is widely used for railway blocking. Principles of three typical demodulating algorithms are presented in details in this paper. Bit error rates ...UM2000 signal is a type of multi-audio frequency-modulated signal which is widely used for railway blocking. Principles of three typical demodulating algorithms are presented in details in this paper. Bit error rates of the three methods at different SNRs are achieved by Monte Carlo simulation experiments. Among the three algorithms, the quadrature demodulation has the best performance at the real working environment. However, the three methods have the same problem of phase hopping when noise is too strong.展开更多
文章设计了一个可以测量并显示信号源输出的被测信号调制度等参数,自主识别并显示被测信号的调制方式(AM、FM、CW),输出解调信号的信号调制度测量装置。作品以TI C2000系列的F28379 DSP为主控制器,使用F28379内置的16 bit 1.1Msps SAR ...文章设计了一个可以测量并显示信号源输出的被测信号调制度等参数,自主识别并显示被测信号的调制方式(AM、FM、CW),输出解调信号的信号调制度测量装置。作品以TI C2000系列的F28379 DSP为主控制器,使用F28379内置的16 bit 1.1Msps SAR ADC在差分模式下进行信号采集。模拟前端包括DDS本振输出和混频器组成的超外差式接收系统,以及一级比较器、一级分频器和一级单端转差分的低失真差分ADC驱动器。解调方案汲取软件无线电的核心思想,综合使用希尔伯特变换、正交解调等方法,可以快速且精确地自主识别被测信号的调制方式,测量并显示调制度等参数,调幅度测量误差小于5‰,调频度和最大频偏测量误差小于2‰,且能输出解调信号波形。展开更多
文摘A program of adaptive quadrature demodulation is proposed to supply the gaps in the traditional analog detection technology of a silicon micro-machined gyroscope (SMG). This program is suitable for digital phase locked loop (DPLL) drive technology that proposed in other papers. In addition the program adopts an adaptive filtering algorithm, which selects the in-phase and quadrature components that are outputs of the DPLL of the SMG's drive mode as reference signals to update the amplitude of the in-phase and quadrature components of the input signal by iteratively. An objective of the program is to minimize the mean square error of the accurate amplitudes and the estimated amplitudes of SMG's detection mode. The simulation and test results prove the feasibility of the program that lays the foundation for the further improvement of the SMG's system performance and the implementation of the SMG system's self-calibration and self-demarcation in future.
基金supported by the National High Technology Research and Development Program of China(No.2011AA010200)
文摘This paper presents the design of a low power （LP） and a low noise figure （NF） quadrature demodula- tor with an on-chip frequency divider for quadrature local oscillator （LO） signal generation. The transconductance stage of the mixer is implemented by an AC-coupled self-bias current reuse topology. On-chip series inductors are employed at the gate terminals of the differential input transconductance stage to improve the voltage gain by enhancing the effective transconductance. The chip is implemented in 65-nm LP CMOS technology. The demod- ulator is designed for an input radio frequency （RF） band ranging from 10.25 to 13.75 GHz. A fixed LO frequency of 12 GHz down-converts the RF band to an intermediate frequency （IF） band ranging from DC to 1.75 GHz. From 10 MHz to 1.75 GHz the demodulator achieves a voltage conversion gain （VCG） ranging from 14.2 to 13.2 dB, and a minimum single-sideband N F （SSB-NF） of 9 dB. The measured third-order input intercept point （lIP3） is -3.3 dBm lbr a two-tone test frequency spacing of 1 MHz. The mixer alone draws a current of only 2.5 mA, whereas the complete demodulator draws a current of 7.18 mA from a 1.2 V supply. The measurement results for a frequency divider, which was fabricated individually, prior to being integrated with the quadrature demodulator, in 65-rim LP CMOS technology, are also presented in this paper.
基金Project supported by the National Key Technology R&D Program of China(No.2011BAI12B02)the Fundamental Research Funds for the Central Universities,China(Nos.2014FZA5019 and 2015FZA5019)
文摘Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency(RF) signal.In quadrature demodulation,RF signal is multiplied with the sine and cosine wave reference signal and then low-pass filtered to produce the base-band complex signal,which has high computational complexity.In this paper,we propose an efficient quadrature demodulation method for B-mode and color flow imaging,in which the RF signal is demodulated by a pair of finite impulse response filters without mixing with the reference signal,to reduce the computational complexity.The proposed method was evaluated with simulation and in vivo experiments.From the simulation results,the proposed quadrature demodulation method produced similar normalized residual sum of squares(NRSS) and velocity profile compared with the conventional quadrature demodulation method.In the in vivo color flow imaging experiments,the time of the demodulation process was 5.66 ms and 3.36 ms,for the conventional method and the proposed method,respectively.These results indicated that the proposed method can maintain the performance of quadrature demodulation while reducing computational complexity.
文摘UM2000 signal is a type of multi-audio frequency-modulated signal which is widely used for railway blocking. Principles of three typical demodulating algorithms are presented in details in this paper. Bit error rates of the three methods at different SNRs are achieved by Monte Carlo simulation experiments. Among the three algorithms, the quadrature demodulation has the best performance at the real working environment. However, the three methods have the same problem of phase hopping when noise is too strong.
文摘文章设计了一个可以测量并显示信号源输出的被测信号调制度等参数,自主识别并显示被测信号的调制方式(AM、FM、CW),输出解调信号的信号调制度测量装置。作品以TI C2000系列的F28379 DSP为主控制器,使用F28379内置的16 bit 1.1Msps SAR ADC在差分模式下进行信号采集。模拟前端包括DDS本振输出和混频器组成的超外差式接收系统,以及一级比较器、一级分频器和一级单端转差分的低失真差分ADC驱动器。解调方案汲取软件无线电的核心思想,综合使用希尔伯特变换、正交解调等方法,可以快速且精确地自主识别被测信号的调制方式,测量并显示调制度等参数,调幅度测量误差小于5‰,调频度和最大频偏测量误差小于2‰,且能输出解调信号波形。
