An Improved Channel Estimation Algorithm Based on Cubic Convolution Interpolation for LOWPM System

L ift ing scheme based orthogonal wavelet packet multiplexing (LOWPM) system can increase the computation efficiency and save storage space. B y using the orthogonality of the translational wavelet function s , LOWPM system efficiently avoids inter-symbol interference (ISI) and inter-channel interference (ICI) . Compared with the orthogonal frequency division multiplexing (OFDM) system, LOWPM system has higher spectrum efficiency and anti-jamming performance. However, in frequency-selective fast-fading channel , the performance of system is still not ideal. In order to implement high bit rate transmission, channel estimation technique is needed to combat noise of the channel. This paper presents an improved channel estimation algorithm in which the cubic convolution interpolation is applied to the pilot based linear minimum mean square error ( L MMSE) channel estimation algorithm so as to get higher estimation accuracy . Simulation results show that, the algorithm can effectively improve the performance of the LOWPM system.

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