基于混沌复合映射算法的150MHz高速码发生器设计

The Design of 150 MHz High Speed Code Generator Based on Chaos Composite Mapping Algorithm

为提高脉冲编码雷达测距分辨率和脉压信噪比等性能指标,介绍一种基于logistics和tent混沌复合映射算法的150MHz高速混沌(Chaos)码发生器。该码发生器采用混沌复合映射算法,经定点化后用VHDL语言在FPGA内实现,最后通过LVDS(高速差分标准)输出。实验结果表明,通过该种方法生成的Chaos序列具有良好的自相关、互相关特性,在保证动态时间不超过码宽度20%的前提下速率高达150 MHz,用于脉冲编码雷达中可以获得距离分辨率为1 m的性能指标。

In order to improve the performance of the pulse code radar,such as the ranging resolution,SNR（ Signalto-Noise Ratio） in processing of pulse pressure and so on,a 150 MHz high-speed Chaos code generator is proposed,which is based on the Logistics and Tent Chaos composite mapping algorithm. The code generator is implemented on the FPGA platform described by VHDL language using fixed algorithms. The Chaos sequence transports using high-speed differential standards（ LVDS）. Experiment results show that the Chaos generated by the methods seems to have perfect autocorrelation and cross-correlation properties. Sequence rates up to 150 MHz when dynamic time does not exceed 20% of the code width. One meter distance resolution can be obtained for the pulse code radar.