摘要
为了满足航天测控信道的要求,提出了一种高性能L频段频率合成器设计的改进方案,采用PLL+DDS+PLL结构实现了小步进、低杂散、低相噪的信号输出。分析了方案的可行性,设计了样品,并进行了测试,结果显示其相位噪声优于-100 dBc/Hz@10 kHz,杂散优于-75 dBc,但附加的杂散信号导致了系统同频干扰。通过分析找出引起同频干扰的机理,并提出了相应的改进措施。所提方案对测控通信、电子对抗等领域中频率合成器的研发具有一定的参考价值。
An improved scheme for L-band high performance frequency synthesizer design is presented to meet the requirement of space TT＆C channel. In this scheme PLL＋DDS＋PLL structure is used to realize small step-size, high spectrum purity and low phase noise. The feasibility of scheme is analyzed, a synthesizer is developed and tested. The result shows that its phase noise is better than -100 dBc/Hz@ 10 kHz and its spurious suppression is better than -75 dBc. But the additive spurious results in co-frequency interference. The reason causing co-frequency interference is found out through analysis and corresponding measures are proposed. The proposed design scheme provides reference for developing synthesizers applied in TT＆C communication and electronic countermeasure（ECM）.
出处
《电讯技术》
北大核心
2014年第7期969-972,共4页
Telecommunication Engineering
