CAJ | 학술논문

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(1 MHz～400 MHz)、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.
개소료직접빈솔합성(DDS)적결구화원리;장DDS여잡산억제기술응용우요감위성모의신호원.재분석DDS해파잡산신호영향적기출상,통과외부려파망락화"여현수정"등기술유효억제료해파잡산화조성;실현료일충기우DDS+FPGA내치식가편정관대저조적빈종원;실험표명해빈종원구유빈대관(1 MHz～400 MHz)、빈솔분변솔고、절환속도쾌、상위조성저등우점,만족통용형요감위성수거모의원계통설계적수구.
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 7th 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～400 MHz), precise resolution, rapid frequency and phase turning.