摘要
AD9957是Analog Devices公司继AD9854和AD9857之后推出的同一系列的新型直接频率合成器件,具有频率分辨率高、工作频段宽、频率转换速度快及良好的调制特性等优点。提出了一种利用AD9957实现直接上变频的全新伽利略伪卫星脉冲调制技术设计方案,给出了系统设计结构,详细介绍了系统工作原理。以伽利略E5信号为例说明了系统设计过程,对AD9957芯片在伪卫星发射机中的应用进行了研究和测试,并给出了脉冲调制的实验结果。
AD9957 is a new DDS device manufactured by Analog Devices company after AD9854 and AD9857. It has many advantages such as high frequency resolution, wide frequency range, rapid frequency conversion and good modulation characteristics. This paper put forward a new design of Galileo pseudolite pulsing transmitter system based on AD9957. It presents the design structure of system and describes in detail the operation principles of system. It takes Galileo E5 signal as an example to show the design process of system, and discuss the use of AD9957 in pseudolite transmitter. Finally, the paper gives the experiment result of pulse modulation.
出处
《无线电通信技术》
2008年第6期21-24,共4页
Radio Communications Technology
