引用本文: | 谢顺钦,谢滔,钟声,等.多指数连续相位调制信号的早迟环定时同步[J].国防科技大学学报,2016,38(4):113-118.[点击复制] |
XIE Shunqin,XIE Tao,ZHONG Sheng,et al.Timing synchronization based on early/late loop with multi-h continuous phase modulation[J].Journal of National University of Defense Technology,2016,38(4):113-118[点击复制] |
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多指数连续相位调制信号的早迟环定时同步 |
谢顺钦1, 谢滔2, 钟声1, 杨春1, 王世练2, 张健1 |
(1.中国工程物理研究院 电子工程研究所, 四川 绵阳 621000;2.国防科技大学 电子科学与工程学院, 湖南 长沙 410073)
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摘要: |
针对多指数连续相位调制信号提出基于序列检测的早迟环定时同步,利用维特比算法的幸存度量构造定时误差估计器。根据误差估计的S曲线和方差,优化定时误差捕获范围和估计精度、消除环路假锁点,同时利用多指数连续相位调制的脉冲幅度调制分解对定时误差估计器进行简化。仿真结果表明,优化后的早迟环定时误差捕获范围最大可达±0.5个符号周期,估计精度在中低信噪比下能够接近修正的克拉美罗界,在高信噪比下也有较好的估计性能;当早迟环定时支路的分支度量简化至最大似然序列检测的1/8时,对多进制、部分响应的多指数连续相位调制信号,造成的解调性能损失小于0.5 dB。 |
关键词: 多指数连续相位调制 定时 早迟环 S曲线 克拉美罗界 |
DOI:10.11887/j.cn.201604018 |
投稿日期:2015-05-07 |
基金项目:国家自然科学基金资助项目(61501484);国防预研基金资助项目(9140A25031013KG01359) |
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Timing synchronization based on early/late loop with multi-h continuous phase modulation |
XIE Shunqin1, XIE Tao2, ZHONG Sheng1, YANG Chun1, WANG Shilian2, ZHANG Jian1 |
(1. Institute of Electronic Engineering, China Academy of Engineering Physics, Mianyang 621000, China;2.College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China)
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Abstract: |
Timing synchronization with the early/late loop scheme based on sequence detection was proposed for multi-h continuous phase modulation. The timing error detector was implemented by the survival metrics of Viterbi algorithm. The so-called S-curve and estimation variance were used for optimizing the acquisition range and tracking performance as well as eliminating false lock points of the loop. Using the PAM (pulse amplitude modulation) representation of multi-h CPM(continuous phase modulation), the proposed timing error detector is simplified. Simulation results show that the estimation range is as large as ±0.5 symbol period, and estimation precision is close to the modified Cramer-Rao bound at medium and low SNR(signal noise ratio), and it also has better estimation performance at high SNR. BER (bit error rate) with simplified schemes are derived. It is demonstrated that when the number of Viterbi metrics is reduced to 1/8 of the maximum likelihood sequence detection, the performance loss is only less than 0.5 dB for M ary or partial response of multi-h CPM. |
Keywords: multi-h continuous phase modulation timing synchronization early-late gate S-curve Cramer-Rao bound |
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