Effective frequency offset correction in OFDM systems with extended Kalman filtering technique

Abstract

Disaster Management System (DMS) is a key solution for humanitarian relief from natural disasters and manmade disasters. This paper discusses the use of Orthogonal Frequency Division Multiplexing (OFDM) in DMS. OFDM is a multicarrier modulation (MCM) in which single data stream is transmitted over a number of lower rate sub carriers. The main reason to use OFDM is to increase the robustness against frequency selective fading and narrow band interference. However an important issue like inter carrier interference (ICI) caused due to Doppler frequency offset and variations in local oscillators distorts the transmitted OFDM signal. In this letter a novel ICI mitigation method which uses Extended Kalman Filter (EKF) is proposed to mitigate the ICI effects. Final simulated results show that the proposed method in this paper outperforms the conventional ICI mitigation techniques.