提出一种新颖的宽带频率合成器方案。采用直接数字频率合成器 (DDS)作为锁相环 (PLL)参考, 实现细步进; 在锁相环中加入一种新颖电路, 实现捷变频; 通过频率扩展方式, 实现宽带频率覆盖; 设计指标可兼顾 2~18 GHz的宽频带以及微秒的捷变频时间。分析了方案及设计中的技术难点, 并给出了解决措施。该频率合成器实测指标良好, 具有较强的工程实用价值, 可推广使用到各型雷达产品中。

A novel frequency synthesizer scheme is proposed. The Direct Digital frequency Synthesizer(DDS) is utilized as the reference of the Phase Locked Loop(PLL) to realize the fine step. The fast frequency hopping is realized by adding a new circuit in the PLL. The frequency expansion is realized by frequency doubling, frequency division and filtering. The frequency range can realize 2-18 GHz and the frequency hopping time can be in the scale of microsecond. The technical difficulties in the scheme and design are analyzed and the improvement methods are given. The frequency synthesizer has good measured indexes and strong practical value in engineering, and can be expanded to other radar systems.