匹配滤波器映射编码方法研究

Mapping encoding method of matched filters

在Vander Lugt相关器中,预先制作的匹配滤波器是系统能否得到较好的相关识别结果的关键。通常使用的迂回相位匹配滤波器编码法数据利用率不高,相关效果有进一步改进的空间。对基于最小欧几里德距离的映射编码法进行了研究,利用空间光调制器的振幅与相位调制特性进行滤波器编码,通过仿真实验分析了匹配滤波函数幅度因子对相关结果的影响,并与迂回相位编码法的相关结果进行了对比分析。从仿真结果可以看出:匹配滤波函数幅度因子越大,相关峰值越高;当幅度因子达到103时,相关峰值达到最大值;此时,映射编码法的相关峰值接近于迂回相位编码法的2倍。因此映射编码法比迂回相位编码法更有利于相关峰的判别。

The matched filter made in advance is the key for good correlation recognition results in Vander Lugt correlator.The data utilization ratio of detour phase encoding method which is always used is low,and its correlation results need to be improved.Mapping encoding method based on the minimum Euclidean distance principle was studied,the filters were encoded by amplitude and phase modulation characteristic of the spatial light modulator,then the effect on the correlation results of the amplitude factors for matched filtering function was analyzed by emulating experiments,and finally the correlation results of two methods were contrasted. Simulation results indicate that the more the amplitude factor is,the higher the correlation peak is;while the amplitude factor reaches 103,the correlation peak reaches its maximal value; and at the time the correlation peak is nearly two times as much as that of detour phase encoding method.Consequently the mapping encoding method is more propitious for the differentiation of correlation peaks than detour phase encoding method.