For the DC offsets caused by traditional implicit sequence based channel estimation in wireless optical communication links
a novel implicit sequence based channel estimation method was proposed to eliminate the DC offsets. Some key factors affecting the system performance were investigated. The maximum output Signal-to-Noise Ratio (SNR) criterion was used to derive the optimal power allocation factor. Then
a simulation experiment was performed to evaluate its mean square error
bit error rate and computational complexity. The results show that the proposed method effectively eliminates the influence of DC offset. on the system performance. Compared to the traditional method
the mean square error is reduced by about 1/2 and the bit error rate is significantly improved. Under the optimal power distribution conditions
when the bit error rate is 4×10
-3
the SNRs of 0.2 and 0.4 DC offset scenarios are improved by about 2 dB and 6d B
respectively
while the computational complexity is only increased by 14.2%.
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references
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