低复杂度的MBOK DS-UWB接收机同步跟踪算法  

Low-complexity synchronization tracking algorithm for MBOK DS-UWB receivers

作　　者：衡量[1] 张盛[2] 张建良[3] 邱见明[1] 陆建华[1] 

机构地区：[1]清华大学电子工程系,北京100084 [2]清华大学宇航技术研究中心,北京100084 [3]清华大学微电子学研究所,北京100084

出　　处：《清华大学学报（自然科学版）》2008年第4期562-566,共5页Journal of Tsinghua University(Science and Technology)

基　　金：国家“八六三”高技术项目(2005AA123310)

摘　　要：为解决频谱搬移方式接收MBOK DS-UWB信号中的载波同步和定时同步问题,提出一种低复杂度的同步跟踪算法,并通过自适应调整环路带宽对同步性能进行优化。所提的同步跟踪算法使用了M/2+2个MBOK相关器和考虑多径效应的匹配模板与微分模板,实现了最大似然准则下的载波相位和定时偏差的联合估计,算法复杂度较低且计算量不随着Rake接收径数量的增加而增加。所提的基于过零数统计和采样点往复跳动检测的自适应带宽调整算法具有很低的计算复杂度,在不延长环路捕获时间的条件下提高了同步环路的跟踪精度并改善了高信噪比时的误比特率性能。A low-complexity carrier and timing synchronization tracking algorithm was developed for the direct downconversion reception of M-ary bi-orthogonal keying direct sequence ultra-wideband （MBOK DS-UWB） signal. Additionally, an adaptive bandwidth adjustment （ABA） algorithm based on zero-crossing counting and sampling point jitter detection was employed. M/2 ＋ 2 MBOK correlators with matching templates and differential templates reckoning in multi-path effects are used for the joint maximal likelihood estimation of carrier phase and symbol timing. Moreover, the computational complexity does not increase with the number of Rake taps. Simulation results show that, with no sacrifice of delayed acquisition, this quite low-complexity ABA algorithm improves the tracking precision of synchronization loops and the bit error rate performance at high signal-to-noise ratio.

关 键 词：超宽带(UWB) MBOK 载波同步 定时同步 自适应带宽调整 

分 类 号：TN92[电子电信—通信与信息系统]