应用于数字阵列的多通道波形产生系统设计

摘要

直接数字频率合成(DDS)是数字阵列雷达(DAR)实现收发数字波束形成的关键技术之一.给出了一种基于DDS技术的多通道波形产生系统的设计方案,该方案在25 cm×12 cm的PCB板上实现了波形产生、波形捷变与幅相控制的系统集成设计.该系统能同时产生16路频率、幅度和相位独立控制的中频雷达信号,满足数字阵列雷达对收发阵列单元的高集成度、小型化、低成本和多功能的要求；系统实现的主要技术指标为:信号带宽1～120 MHz可变,通道隔离度大于60 dBc,窄带脉内信噪比大于65 dBc,满足数字阵列雷达技术指标的要求.%DDS is one of the key technologies to achieve T/R all digital beam forming in digital array radar (DAR). A design scheme of multi-channel waveform generation system based on DDS has been presented, in which system integration design including waveform generation, waveform agility and amplitude/phase control has been fabricated in a single 25 cm X 12 cm PCB. 16 channel IF radar signals with frequency, amplitude and phase controlled independently can be generated in the system, which satisfies the needs of high integration, miniaturization, low cost and multi-function in the T/R modules of DAR. The main technology specification of the system show that the signal bandwidth is 1 -120 MHz changeably, isolation among channels is above 60 dBc, SNR of narrow band is superior to 65 dBc, which fulfill the requirements in DAR.