A Low-Complexity Pilot-Based Frequency-Domain Channel Estimation for ICI Mitigation in OFDM Systems

A low-complexity pilot pattern and a frequency-domain channel estimation method for Inter-Carrier Interference (ICI) mitigation is proposed Orthogonal Frequency Division Multiple Access (OFDM) systems. The exploits the band structure of coupling matrix to perform an ICI-free in frequency domain. This relies on some conditions imposed over that simplify complexity significantly, since its same as classical least squares (LS) used low mobility scenarios. Then, ICI removed by using modified version Minimum Mean Square Error (MMSE) equalization, which reduces computational considerably. MMSE equalization sparse banded variant Cholesky decomposition, named LDLH factorization. It shown greatly improves Bit Rate (BER) high Signal-to-Noise Ratio (SNR) regime.