同步误差下OFDM稀疏信道估计

王小舟; 张 严; 胡友峰

doi:10.11993/j.issn.1673-1948.2013.02.004

同步误差下OFDM稀疏信道估计

doi: 10.11993/j.issn.1673-1948.2013.02.004

中国船舶重工集团公司第705研究所昆明分部, 云南昆明, 650118

基金项目: 船舶工业国防科技基金资助项目

详细信息

作者简介:
王小舟(1987-), 男, 在读硕士, 主要研究方向为水下通信技术.

中图分类号: TJ630.34
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- 被引次数: 0
出版历程
- 收稿日期: 2012-10-29
- 修回日期: 2013-02-25
- 刊出日期: 2013-04-20

Sparse Channel Estimation of OFDM with Synchronization Errors

Kunming Branch of the 705 Research Institute, China Shipbuilding Industry Corporation, Kunming 650118, China

摘要

摘要: 在实际正交频分复用(OFDM)水声通信中, 当直达声能量较弱时, 存在较大的同步误差, 导致梳状导频最小二乘信道估计出现混叠。在分析了同步误差对最小二乘(LS)信道估计算法影响的基础上, 提出了一种在同步误差下可稳定工作的OFDM稀疏信道估计算法, 并建立了稀疏信号重构的模型。该方法将存在同步误差时的信道估计认为是通过不完整频域采样重构稀疏信号的问题, 利用压缩感知算法进行信道估计。在同步误差严重的情况下, 可以取得较好的信道估计效果, 从而降低误码率。湖试试验验证了该方法的有效性。
- 水声通信 /
- 正交频分复用 /
- 稀疏信道估计 /
- 同步误差 /
- 压缩感知
Abstract: An estimation algorithm of orthogonal frequency division multiplexing(OFDM) channel, which is robust with synchronization errors, is introduced. The severe synchronization error in general underwater channel might cause the aliasing in comb-pilot least square(LS) algorithm based channel estimation, if the strongest signal arrival is not the first one, therefore, a new OFDM sparse channel estimation algorithm is proposed by analyzing the influence of synchroni-zation errors on the LS channel estimation algorithms. In the proposed estimation algorithm, sparse channel estimation with synchronization errors is equivalent to reconstructing a sparse signal from incomplete frequency samples. Some pseudo randomly picked subcarriers are used as pilots, and the compressed sensing(CS) algorithm is adopted for the sparse channel estimation. This algorithm can achieve better performance when synchronization error is large. Lake trial verifies the effectiveness of the proposed algorithm.
- underwater acoustic communication /
- orthogonal frequency division multiplexing(OFDM) /
- sparse channel estimation /
- synchronization error /
- compressed sensing

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参考文献(9)

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