Design of Adaptive Gain Acquisition System Based on Magnetic Speed Signal
Aimed at the linear variation in the amplitude of the electromotive force signal generated by the coil magnetic sensors with the change of measuring speed,in order to realize the distortion-free acquisition of such amplitude and periodic dynamic change signals,this paper proposes an adaptive gain acquisition system with gain varying with input signal amplitude.The system takes field programmable gate array(FPGA)as a control core,analyzes the input signal amplitude,and adaptively controls the circuit gain with-in the range of-20～80 dB according to the amplitude analysis result,records the current gain of the system,restores the input sig-nal according to the current gain,and synchronously stores the gain signal and restore signal.The collected output signal amplitude with adaptive gain is controlled within the set range,the signal change details are directly observed in different amplitude ranges of dy-namic signal.Through the speed signal input test within the range of 20 μV～10 V,the signal amplitude of the system with the adap-tive gain is controlled within the range of 0.1～4 V,which achieves the dynamic speed signal without distortion and verifies the per-formance of the adaptive gain acquisition circuit.It has a good application prospect in dynamic signal acquisition field with high amplitude.
motional electromotive forcespeed measurementFPGAadaptive gainsignal acquisition system
万方数据
维普
