【摘要】 传统的微波阵列成像系统采用直接测量接收天线信号的方式,其测量数据动态范围广,参数灵敏度差异大,信噪比特性较差,这些不足限制了成像质量的进一步提高。针对这一问题,提出了一种测量天线对信号差值的测量模式。文中对16天线传感阵列的差值测量模式进行了理论分析和基于有限元方法的仿真实验。分析和实验结果表明,差值测量模式可显著提高测量数据的幅度值,改善数据的信噪比特性,同时还能够均衡参数灵敏度差异,减小测量数据动态范围,降低对数据采集系统精度的要求,提高微波阵列成像系统性能。更多还原

【Abstract】 Conventional microwave tomography(MT)adopted direct measurement pattern,its measured data from receiving antenna is wide in dynamic range,unbalanced in parameter sensitivity and poor in signal to noise ratio(SNR)characteristic.These features restrict it to enhance image quality.To combat these deficiencies,a difference measurement pattern was proposed,which measured signal difference among each pair of receiving antennas.Theoretical speculation and simulation experiment based on finite element method were conducted to evaluate the performance of difference measurement pattern on 16-antenna sensor array. Experiment results show that difference measurement pattern could increase amplitude values,reduce dynamic range of data,improve SNR characteristic,balance parameter sensitivity,lower the requirement for acquisition system and enhance performance of microwave tomography.更多还原