OFDM系统中一种实用的干扰抑制信道估计算法

doi:10.11959/j.issn.1000-0801.2016013

摘要/Abstract

摘要：

针对OFDM系统中LS信道估计在噪声消除和干扰抑制上的不足，提出一种干扰抑制信道估计算法。算法利用OFDM信号的时频二维特性，在LS信道估计基础上通过3次FFT/IFFT实现信道噪声消除和窄带干扰抑制，算法复杂度低，具有较好的工程可行性。算法仿真结果表明，这种干扰抑制的信道估计性能比传统LS信道估计在多径信道下的性能提升3 dB以上，在有窄带干扰的场景下系统性能损失在1.5 dB以内。

关键词: OFDM, 信道估计, 干扰抑制

Abstract:

In OFDM system,the least square（LS）algorithm has the shortage of noise cancelling and interference suppressing.An utility channel estimation algorithm which took advantage of the time frequency characteristic in OFDM system was proposed.The new channel estimation algorithm realized noise cancelling and interference suppressing through time-frequency transform by three times.In view of time-frequency transform could be achieved by FFT/IFFT,the new channel estimation algorithm complexity was low.In the TU channel simulation,the new channel estimation algorithm has the high performance,which was 3 dB better than the LS algorithm.In the TU channel simulation with interference suppression,the new channel estimation algorithm has only 1.5 dB reduction in performance.

Key words: OFDM, channel estimation, interference suppression

赖晓阳,朵琳. OFDM系统中一种实用的干扰抑制信道估计算法[J]. 电信科学, 2016, 32(1): 88-92.

Xiaoyang LAI,Lin DUO. Utility channel estimation algorithm with interference suppression in OFDM system[J]. Telecommunications Science, 2016, 32(1): 88-92.

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传播路径	功率/dBm	时延/ns
0	-3	0
1	0	200
2	-2	600
3	-6	1 600
4	-8	2 400
5	-10	5 000