高灵敏度微小卫星可变带宽接收机设计  

Design of variable loop bandwidth high sensitivity micro-satellite receiver

作　　者：张朝杰[1] 金小军[1] 杨伟君[1] 金仲和[1] 

机构地区：[1]浙江大学信息与电子工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2011年第4期660-664,共5页Journal of Zhejiang University：Engineering Science

基　　金：教育部新世纪优秀人才支持计划资助项目(NCET-06-0514);中国博士后科学基金资助项目(20081458)

摘　　要：针对微小卫星发射功率低、天线增益小的特点对星载测控应答机提出的高接收灵敏度及高动态范围要求,研究卫星接收机的实现方法.提出一种基于正交欠采样技术及全数字载波恢复环的可变带宽卫星接收机结构.在全数字载波恢复环的实现中,通过相干自动增益控制(AGC)来控制环路带宽,使得在高信噪比下的环路带宽增大,从而获得更佳的跟踪性能;在低信噪比下,降低环路带宽使得接收机有更高的接收灵敏度.经实验测试可知,在250Hz环路带宽下,接收灵敏度为-144dBm,动态范围达到80dB以上.The characteristic of low transmit power and antenna gain in micro-satellite requires high receiver sensitivity and high dynamic range for board transponders. A variable loop bandwidth receiver architecture based on all digital carrier recovery loop was presented using I/Q sub-sampling technique. A coherent automatic gain control （AGC） was used in order to control the loop bandwidth. The loop bandwidth was expanded to achieve better tracking performance at high signal to noise ratio; the loop bandwidth was decreased to realize high receiver sensitivity at low signal to noise ratio. --144 dBm receiver sensitivity was achieved and the dynamic range was better than 80 dB under the condition of 250 Hz loop bandwidth.

关 键 词：载波恢复环 相干自动增益控制(AGC) 正交欠采样 灵敏度 可变带宽 

分 类 号：TN927[电子电信—通信与信息系统]