Title :
OFDM Channel Prediction Using Fuzzy Update LMS Algorithm in Time-Variant Mobile Channel
Author :
Wen, Jyh-horng ; Chang, Cheih-Yao ; Lee, Gwo-Ruey ; Huang, Ching-Yao
Author_Institution :
Inst. of Electr. Eng., Nat. Chung Cheng Univ., Min-Hsiung
Abstract :
Channel predictor implemented by discrete Fourier transform (DFT) is considered, which predict the channel gain of each receiving path by adaptive filters. A fuzzy logic controlled step size could overcome the drawback of conventional least-mean-square error (LMS) algorithm. In this paper, LMS algorithm with fuzzy updated step size is proposed to realize the adaptive channel prediction in orthogonal frequency division multiplexing (OFDM) systems. Simulation results show that as compared to conventional LMS algorithm, the proposed algorithm can achieve a faster convergence rate and lower steady-state mean square error. The proposed algorithm can also achieve more robust tracking ability in the various channel environments.
Keywords :
OFDM modulation; adaptive filters; discrete Fourier transforms; fuzzy control; least mean squares methods; mobile radio; time-varying channels; wireless channels; DFT; OFDM channel prediction; adaptive filter; convergence rate; discrete Fourier transform; fuzzy logic control; fuzzy update LMS algorithm; orthogonal frequency division multiplexing; steady-state mean square error; time-variant mobile channel; tracking analysis; Adaptive filters; Convergence; Discrete Fourier transforms; Error correction; Fuzzy logic; Fuzzy systems; Least squares approximation; OFDM; Size control; Steady-state;
Conference_Titel :
Vehicular Technology Conference, 2006. VTC-2006 Fall. 2006 IEEE 64th
Conference_Location :
Montreal, Que.
Print_ISBN :
1-4244-0062-7
Electronic_ISBN :
1-4244-0063-5
DOI :
10.1109/VTCF.2006.404
