The Principles of coherent interference suppression are presented by a three-sensor array. The formulae of extracting expected signals from strong interference are derived. The selection of sensor space is discussed a...The Principles of coherent interference suppression are presented by a three-sensor array. The formulae of extracting expected signals from strong interference are derived. The selection of sensor space is discussed and then relationships between the space and frequency point, at which the signals can be extracted, are given. When expected signals are band- limit, the conditions of the selected sensor space, which should be satisfied, are given. Lastly, Performance of interference suppression is analyzed when the amplitude of interference power spectra of signals Received by three sensors fluctuates, and the expressions of relative error of the extracted signals and processing gain are derived. The theoretical and simulation results show that signals can be extracted from strong background interference without any information about signals and interference expect for the arriving direction of signals, that the space between sensors should be smaller than half wavelength of upper limit freqency when the expected signals are band-limit, and that performance of extracting signals will decline with the increase of fluctuation of interference spectrum amplitude.展开更多
基于传统高频脉振信号注入法在信号解调过程中引入多滤波器会导致转子位置估计存在相位滞后、动态响应与滤波性能无法兼顾等问题,基于向两相静止坐标轴系注入高频脉振信号,采用三频陷波器(Triple Frequency Notch Filter,TFNF)取代传统...基于传统高频脉振信号注入法在信号解调过程中引入多滤波器会导致转子位置估计存在相位滞后、动态响应与滤波性能无法兼顾等问题,基于向两相静止坐标轴系注入高频脉振信号,采用三频陷波器(Triple Frequency Notch Filter,TFNF)取代传统信号解调策略,略去了带通滤波器(Band-Pass Filter,BPF),此外,提出一种改进的锁相环(Phase-Locked loop,PLL)算法,消除了位置观测环中注入电压及电机电感参数的影响,并解调出转子位置信息。最后通过MATLAB/Simulink仿真对两种控制策略进行对比,结果显示改进型位置信号解调策略降低了系统转速及转子位置估计误差,验证了该方法的有效性。展开更多
为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行...为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行浸渍处理,成功开发了一种性能优异的CNT包覆三维ES/PET非织造基压力传感器,并对比分析了不同CNT浸渍时间和浸渍次数对传感器性能的影响。研究结果显示,该CNT包覆三维ES/PET非织造基柔性压力传感器具有高达0.375 kPa^(-1)的灵敏度和0~214.526 kPa的检测范围。经过2100次压缩循环,传感器展现了优异的稳定性和可重复性,响应时间为48 ms,恢复时间为122 ms。在实际应用中,该传感器能够精确识别如呼吸、吞咽、手指弯曲等人体细微生理活动,在运动、医疗、虚拟现实等多个领域具有潜在的广泛应用。展开更多
文摘The Principles of coherent interference suppression are presented by a three-sensor array. The formulae of extracting expected signals from strong interference are derived. The selection of sensor space is discussed and then relationships between the space and frequency point, at which the signals can be extracted, are given. When expected signals are band- limit, the conditions of the selected sensor space, which should be satisfied, are given. Lastly, Performance of interference suppression is analyzed when the amplitude of interference power spectra of signals Received by three sensors fluctuates, and the expressions of relative error of the extracted signals and processing gain are derived. The theoretical and simulation results show that signals can be extracted from strong background interference without any information about signals and interference expect for the arriving direction of signals, that the space between sensors should be smaller than half wavelength of upper limit freqency when the expected signals are band-limit, and that performance of extracting signals will decline with the increase of fluctuation of interference spectrum amplitude.
文摘为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行浸渍处理,成功开发了一种性能优异的CNT包覆三维ES/PET非织造基压力传感器,并对比分析了不同CNT浸渍时间和浸渍次数对传感器性能的影响。研究结果显示,该CNT包覆三维ES/PET非织造基柔性压力传感器具有高达0.375 kPa^(-1)的灵敏度和0~214.526 kPa的检测范围。经过2100次压缩循环,传感器展现了优异的稳定性和可重复性,响应时间为48 ms,恢复时间为122 ms。在实际应用中,该传感器能够精确识别如呼吸、吞咽、手指弯曲等人体细微生理活动,在运动、医疗、虚拟现实等多个领域具有潜在的广泛应用。
