Adaptive Inter-atom Interference Mitigation Approach to Sparse Multi-path Channel Estimation

Impulse response of multi-path channel can be estimated by using a short training sequence when the channel is sparse. Though the ordinary orthogonal matching pursuit (OMP) provides fast sparse multi-path channel (SMPC) estimation, it suffers from inter-atom interference (IAI), especially in the case of SMPC with a large delay spread and short training sequence. Herein, an adaptive IAI mitigation method is proposed to improve OMP algorithm based on a sensing dictionary, which is utilized to prevent false atoms from being selected due to serious IAI. Numeral experiments illustrate that the improved OMP algorithm based on adaptive IAI mitigation outperforms both the ordinary OMP algorithm.