Title :
A new synchronization algorithm for OFDM systems in multipath environment
Author :
Wang, Lidng ; Shan, Xiuming ; Ren, Yong
Author_Institution :
Dept. of Electron. Eng., Tsinghua Univ., Beijing, China
Abstract :
Carrier frequency and symbol timing errors may greatly degrade the performance of the orthogonal frequency division multiplexing (OFDM) system, especially in multipath environment. We explore the cyclostationarity of OFDM signals, which only relies on second order statistics, to estimate the synchronization offset. First, a coarse carrier frequency offset estimator for multipath environment is developed using the second order statistics of the received OFDM signal. It has a wide capture range though not accurate. Second, we introduce a new synchronization algorithm based on cyclostationarity and matched filter theories, which can get the maximal estimation SNR in multipath environment. Both estimators utilize channel state information to achieve better estimation performance and are non-pilot aided. They can be combined to form a whole OFDM synchronizer in multipath environment. Finally, simulations confirm the performance of the estimation algorithm.
Keywords :
OFDM modulation; filtering theory; matched filters; multipath channels; statistical analysis; synchronisation; timing; OFDM synchronizer; OFDM systems; capture range; carrier frequency timing errors; channel state information; coarse carrier frequency offset estimator; cyclostationary OFDM signals; estimation algorithm performance; estimation performance; matched filter; maximal estimation SNR; multipath environment; orthogonal frequency division multiplexing; received OFDM signal; second order statistics; simulations; symbol timing errors; synchronization algorithm; AWGN; Algorithm design and analysis; Baseband; Digital video broadcasting; Filters; Frequency synchronization; Multipath channels; OFDM; State estimation; Timing;
Conference_Titel :
Communication Systems, 2002. ICCS 2002. The 8th International Conference on
Print_ISBN :
0-7803-7510-6
DOI :
10.1109/ICCS.2002.1182476