Iterative Frequency Domain Combining Equalization Algorithm for Single Carrier Systems
Qiao Liang① Xin Ji-rong①② Zheng Hui①
①(National Key Laboratory of Science and Technology on Blind Signal Processing, Chengdu 610041, China) ②(College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China)
To combat the effect of InterSymbol Interference (ISI) while transmitting data over wireless fading channels, the issue of single carrier communication signal receiving with multiple antennas is studied and an iterative frequency domain combining equalization algorithm is proposed. The proposed algorithm derives the theoretical frequency domain transfer function of the combining equalizer with a priori information. An efficient implementation is proposed which employs the Fast Fourier Transform (FFT) to compute the combining equalizer coefficients and equalization filter. Numerical results show that the proposed algorithm reduces complexity enormously with nearly no performance loss compared with the time domain algorithm. Compared with Single Carrier Frequency Domain Equalization (SC-FDE), the Cyclic Prefix (CP) overhead can be avoided, and the computationally efficient frequency domain algorithm can be applied to the existing single carrier communication systems.
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