摘要
介绍了直接频率合成(DDS)的结构和原理;将DDS与杂散抑制技术应用于遥感卫星模拟信号源。在分析DDS谐波杂散信号影响的基础上,通过外部滤波网络和"余弦修正"等技术有效抑制了谐波杂散和噪声;实现了一种基于DDS+FPGA内置式可编程宽带低噪的频综源;实验表明该频综源具有频带宽(1MHz~400MHz)、频率分辨率高、切换速度快、相位噪声低等优点,满足通用型遥感卫星数据模拟源系统设计的需求。
The techniques of direct digital synthesizer and harmonic spurs reduction were applied in the system of remote sensing satellites simulator frequency synthesizer. Key technologies and principle of DDS are introduced. Main harmonic spurs of DDS devices are discussed, and the primary means of spurious suppression methods are introduced, which use the techniques of 7^th order elliptical differential low-pass filter and cosine correction. The wideband and low spurs frequency synthesizer was designed,which based on FPGA and new DDS devices. And finally, a conclusion is made through experiments that the frequency synthesizer features wide-band(1 MHz-400MHz),precise resolution, rapid frequency and phase turning.
出处
《传感技术学报》
CAS
CSCD
北大核心
2009年第12期1768-1773,共6页
Chinese Journal of Sensors and Actuators
基金
遥感卫星应用国家工程实验室项目资助(发改办高技[2008]622号)