| 摘要: |
| 遥测测距是美国喷气推进实验室于2010年提出的新型测距方法，其核心思想是将测距信息插入遥测帧中下发，利用一路遥测信号同时完成遥测、测距两种功能，地面站对帧头到达时刻的估计精度直接影响测距精度。针对现有DTTL符号同步算法精度不高的问题，研究了一种基于加权系数的DTTL符号同步算法，通过对每个遥测符号首位、末位采样点进行加权处理再积分的方法，有效提高了符号同步精度，仿真进一步验证了方法的有效性，结果表明该算法在信噪比为-5dB时能达到现有算法理想条件下的性能，均方差约为0.01个遥测符号。 |
| 关键词: 遥测测距 符号同步 数据转换跟踪环路 帧头 |
| DOI：DOI:10.3969/j.issn.1672-2337.2020.01.009 |
| 分类号:TN919.3+4 |
| 基金项目:北京市科技重大专项（No.Z1811001002918004） |
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| Telemetry Ranging Symbol Synchronization Based on Weighted Coefficient DTTL Algorithm |
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HOU Yanbing，JIAO Yiwen，YANG Wenge
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Department of Electronics and Optical Engineering，Aerospace Engineering University，Beijing 101416，China
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| Abstract: |
| Telemetry ranging is a new ranging method proposed by JPL in 2010. The core idea is to insert the ranging information into the telemetry frame and use the only one telemetry signal to complete both telemetry and ranging functions. The accuracy of the estimation arrival time of the attached synchronization marker by the ground station directly affects the ranging accuracy in telemetry ranging. Aiming at the problem that the existing DTTL symbol synchronization algorithm is not accurate enough，a weighted sum DTTL symbol synchronization algorithm is proposed. By weighting the first sample and the last sample of each telemetry symbol in summation and then integrating，the synchronization accuracy is effectively improved. Simulation is carried out to further verify the effectiveness of the proposed method. The results show that the proposed algorithm can achieve the performance of the existing algorithm under the ideal conditions at SNR of -5dB，and the mean square error is about 0.01 telemetry symbols. |
| Key words: telemetry ranging symbol synchronization data transition tracking loop (DTTL) attached synchronization marker (ASM) |
