摘要
设计了一种基于直接数字频率合成器(direct digital frequency,DDS)与现场可编程门阵列(field programmable gate array,FPGA)的雷达目标模拟系统频率源方案。采用自顶向下的设计方法开发系统控制代码。对DDS控制字计算公式转换,有效地解决了浮点乘法运算等效成高精度的定点运算。实现了分辨率为10kHz,500MHz带宽的全频段捷变,脉内线性调频信号带宽按照25Hz步长和调频时间按照10ns步长大范围控制的X波段频率源,频率捷变时间达到900ns,并给出了具体实验结果。
A frequency synthesizer mechanism of Radar target simulation system was designed in this paper, which is based on DDS and FPGA. The system control code was developed by adopting the top-down design way. The floating-point multiplication was equivalent to multiplication of fixed point by transforming the DDS instruction words formula. The X-band synthesizer was realized, and had the feature of fast frequency switching at 10 kHz resolution and 500 MHz bandwidth, its linearly frequency modulated signal bandwidth can large-scale controlled by the step of 25 Hz and the time by the step of 10 ns. The switching time was 900 ns. Some experimental results also were presented at the end.
出处
《重庆邮电大学学报(自然科学版)》
北大核心
2010年第5期560-565,共6页
Journal of Chongqing University of Posts and Telecommunications(Natural Science Edition)
基金
国家自然科学基金(60801024)~~
关键词
直接数字频率合成(DDS)
现场可编程门阵列(FPGA)
捷变频
线性调频
direct digital frequency synthesis (DDS)
field programmable gate array( FPGA )
fast frequency switching
line- arly frequency modulated( LFM )