基于AD9910的宽带捷变频频率合成器设计

Design of broadband frequency agile frequency synthesizer based on AD9910

选取了内部时钟可以达到1 GHz,输出频率最高可达400 MHz的高性能DDS芯片AD9910作为核心器件,设计了500 MHz捷变带宽的频率合成器。分析了AD9910的宽带动态不失真范围(SFDR),选取了合适的频段进行捷变频率合成。应用了混频的方法,在保证低噪声的前提下,产生频率捷变带宽500 MHz、跳频时间可达亚微秒级的捷变信号,满足宽带频率捷变的要求。

The DDS chip AD9910 is adopt,in which internal clock is 1 GHz and the maximum output frequency is 400 MHz,and the fast hopping frequency synthesizer is designed which broadband is 500 MHz. The AD9910＇s spurious free dynamic range（SFDR）is analysed and the appropriate frequency band is selected to finish fast broadband frequency hopping. In the premise of ensuring low noise, fast hopping frequency synthesizer of which bandwidth is 500 MHz and the frequency hopping time is less than 1 us is designed in mixing method, which meet the requirements of wideband frequency agilit.