A Novel Iterative Channel Estimation Technique for Multipath Fading Channels in MIMO-OFDM Using Auxiliary Pilots

Abstract

The paper proposes a novel iterative channel estimation technique for multipath fading channels in Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing(MIMO-OFDM)systems with Gaussian noise and impulse noise. MIMO-OFDM systems can be beneficial if the estimated channel quality is assured at the receiver. The paper also proposes an auxiliary pilot for channel re-estimation based on some reliably retrieved data symbols. In subsequent iterations, adding new auxiliary pilots improves channel estimation accuracy. The correlation between the data channel coefficients and the original pilots is used to select reliable data. Since iterative channel estimation is time-consuming, using a channel estimator with a low processing time and computational complexity is imperative. An easy-to-implement baseline least squares(LS)method is used in the proposed estimator. According to the simulation results, the proposed iterative channel estimation technique improves MIMO-OFDM performance by increasing the number of pilots in subsequent iterations compared to the conventional channel estimation techniques.

Keywords

• multi-path fading
• auxiliary pilots
• mimo-ofdm
• channel re-estimation