电磁定位耦合信号提取方法研究

电磁定位系统中,正弦耦合信号提取是关键,其结果将直接影响定位精度.在多频正弦信号耦合系统中,由于电子元器件和系统误差等原因,会导致信号频率有偏差,而且可能存在饱和畸变,对参数提取造成了困难.基于最小二乘法原理和频率逼近思想,提出一种用于有频偏的多频率有饱和正弦信号幅值和相位的提取方法.该方法在有饱和畸变的正弦信号中提取未饱和的样本,通过最小二乘法拟合计算,估计信号参数,然后改变信号频率逐渐逼近最佳频率,使得误差平方和最小,从而提取准确参数.仿真分析了噪声、信号饱和程度和采样点数对参数提取的影响.最后通过实验验证了该方法的有效性和实用性.

Research on Signal Extraction Method for Coupling Signals of Electromagnetic Localization

The sinusoidal coupling signal extraction is crucial in electromagnetic positioning system. The result will affect the accuracy of localization directly. In the multi-frequency sinusoidal signal coupling system,saturation dis-tortion and frequency deviation caused by electronic components and system errors and other reasons will make it difficult to extract the signal parameters. This paper presents a method based on the theories of least squares and frequency approximation to recovery amplitude and phase from multi-frequency saturated sinusoidal signals with fre-quency offset. The method extracts the unsaturation samples in the sinusoidal signal. The least squares method is used to calculate the signal parameters,and then change the signal frequency to approximate to the optimal frequen-cy which makes squared error the minimum to estimate the exact parameters. The influence of noise,saturation de-gree and sampling number on parameter extraction are analyzed in simulation. Finally,the experiments show the ef-ficacy and practicability of the method.