星载双频雷达高度计中频数字接收模块设计及性能测试  

Design and realization of an IF digital receiving module for space-borne double-frequency radar altimeter

作　　者：唐月英[1,2] 许可[1,2] 刘鹏[1,2] 于秀芬[1,2] 

机构地区：[1]中国科学院微波遥感技术重点实验室,北京100190 [2]中国科学院国家空间科学中心,北京100190

出　　处：《电子测量技术》2017年第4期15-21,共7页Electronic Measurement Technology

摘　　要：在星载双频雷达高度计系统数控单元中实现中频数字接收功能,研究采样时钟设计、基于FPGA采用优化正交解调多相滤波抽取结构的数字中频接收等关键技术;性能测试时提出了分别对中频模数转换和数字下变频处理进行测试,以检验硬件电路设计和数字下变频处理各自的性能;测试方案根据现有的软件和仪器设备条件进行设计,选择满足相干FFT采样条件的纯正弦信号作为输入信号。测试结果表明,中频模数转换信噪比接近器件厂商的评估值,通频带内8位基带采样的信噪比优于系统要求。A DCU（data control unit）with IF receiving function for a space-borne double-frequency radar altimeter is developed.The key techniques such as the design of clock scheme for IF A/D converter and the implementation of the IF receiving adopted an optimum poly-phase filter structure combining decimation and quadrature demodulation based on FPGA are studied;The performance between the IF A/D converter and the DDC are tested separately in order to analyze and identify their performance respectively.The testing methods are designed according to the current software and equipment.Some special frequency of sinusoid that meet coherent FFT for ADC testing are selected as inputs.The test results show that the SINAD of the IF A/D conversion close to the evaluation value of the device manufacturer’s own tests,and the SINAD of the base-band A/D sampling exceeds the required by the system.

关 键 词：模数转换 数字中频接收 多相滤波器 相干采样 

分 类 号：TN957.5[电子电信—信号与信息处理]