An Evaluation of Channel Estimation in Mobile OFDM Systems Using OMP: A Performance Analysis

Abstract

We propose an analytical framework that introduces 4 normalized mean-square-errors (NMSEs) for assessing the performance of a system: total NMSE (NMSET), NMSE on dominant channel components (NMSED), NMSE caused by 'lost errors' (NMSEL), & NMSE caused by 'false alarms' (NMSEF). To establish an upper-bound for NMSED under optimal conditions, we derive a closed-form formula (NMSED;UB). The key findings derived from our analytical model reveal that the deterministic pilot pattern, maximum Doppler shift, quantity of dominant multipath components, and signal-to-noise ratio (SNR) collectively influence NMSED;UB. When the probability of success for Orthogonal Matching Pursuit (OMP) exceeds a specific threshold, NMSED;UB can serve as an approximation of the practical NMSE (NMSET). Additionally, leveraging suggested NMSED;UB, linear regression models demonstrate promising capability in predicting actual bit-error-rate performance. Consequently, our suggested model offers a valuable tool for adaptively optimizing pilot parameters in mobile Orthogonal Frequency Division Multiplexing (OFDM) systems, aligning with rapidly changing channel conditions.