Title :
Particle Filtering for Tracking Time-Varying Dispersion Channels in OFDM Systems
Author :
Qin, Wen ; Peng, Qicong
Author_Institution :
Inst. of Commun. & Inf. Eng., Univ. of Electron. Sci. & Technol. of China, Chengdu
Abstract :
Orthogonal frequency-division multiplexing (OFDM) is robust against frequency selective fading due to the increase of the symbol duration. However, for mobile applications, channel time-variations in one OFDM symbol introduce inter-carrier interference (ICI) which degrades the performance. This becomes more severe as mobile speed, carrier frequency or OFDM symbol duration increases. Therefore, the performance of coherent OFDM systems greatly depends on the ability to accurately estimate the effective dynamic channel. In this paper, we analyze the ICI in OFDM systems when it operates over time-varying dispersion channels, and build an auto-regressive (AR) model of the channel dynamics based on the Jakes´ model. A pilot symbol aided particle filter method is presented for the estimation and tracking of the channel. Finally, simulation result shows how the proposed method would improve the performance of OFDM systems
Keywords :
OFDM modulation; autoregressive processes; channel estimation; intercarrier interference; mobile radio; particle filtering (numerical methods); time-varying channels; Jakes model; OFDM systems; autoregressive model; carrier frequency; channel dynamics; channel estimation; channel time-variations; frequency selective fading; inter-carrier interference; mobile applications; mobile speed; orthogonal frequency-division multiplexing; pilot symbol aided particle filter method; time-varying dispersion channels; Degradation; Fading; Filtering; Frequency division multiplexing; Interference; OFDM; Particle filters; Particle tracking; Robustness; Time varying systems;
Conference_Titel :
Information Theory Workshop, 2006. ITW '06 Chengdu. IEEE
Conference_Location :
Chengdu
Print_ISBN :
1-4244-0067-8
Electronic_ISBN :
1-4244-0068-6
DOI :
10.1109/ITW2.2006.323735