大调制度微波统一测控系统载波捕获算法  

Carrier acquisition algorithm with large modulation index for unified microwave TT&C systems

作　　者：赖卫东[1] 詹亚锋[1] 陆建华[1] 

机构地区：[1]清华大学电子工程系,北京100084

出　　处：《清华大学学报（自然科学版）》2009年第7期956-959,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(60532070);国家重点基础研究发展计划资助项目(2007CB310601)

摘　　要：深空测控链路余量紧张时,可适当增大信号调制度,使有限的发射功率更多地分配于副载波。针对大调制度导致载波能量过小,不能有效实现载波捕获,使得信号无法正常接收等问题,该文提出用于大调制度的基于载波能量中心的迭代搜索算法和伪对称点最小误差判定方法,在不需要先验知识的情况下能实现对载波的有效捕获。仿真表明,在副载波信号C/N0>34 dBH z时载波一次捕获概率达95%以上。该方法可很好地满足大调制度微波统一测控系统的工程应用要求。In deep space communications, the limited link margin can be improved by the use of a large modulation index, which allocates more transmitting power to side carriers. However, the large modulation index leads to less energy in the central carrier, so traditional methods can not effectively acquire the central carrier. This paper presents an iterative search algorithm to capture the carrier without prior knowledge based on the carriers energy center and a decision scheme using pseudo-symmetry points with the smallest error. Simulations show that the probability of one time acquisition of the central carrier is more than 95% when the C/N0 of the side carriers is higher than 34 dBHz. The method efficiently improves practical unified microwave systems with large modulation indexes.

关 键 词：测控系统 载波捕获 载波错锁 

分 类 号：TN92[电子电信—通信与信息系统]