Title :
Optimum frame and frequency synchronization for OFDM systems
Author :
You, Charles J. ; Horng, J. Henry
Author_Institution :
Mitsubishi Electr. Res. Labs., Murray Hill, NJ, USA
Abstract :
In this paper, we propose an optimum frame and carrier frequency synchronization method for a burst type orthogonal frequency division multiplexing (OFDM) application such as a wireless local area network (WLAN). In the case of burst transmission, rapid frequency synchronization is essential in order to rapidly achieve orthogonality among subcarriers. By estimating the frequency offset and timing offset before and after the demodulation we can achieve acquisition within one OFDM symbol period. Due to the subcarrier ambiguity in the maximum likelihood estimation (MLS) frequency detector before demodulation, the maximum correctable frequency range is limited to ±1/2 of the subcarrier spacing. This problem can be solved by using a frequency acquisition method after FFT
Keywords :
OFDM modulation; delay estimation; demodulation; fading channels; frequency estimation; maximum likelihood estimation; synchronisation; wireless LAN; FFT; OFDM systems; WLAN; acquisition; burst transmission; burst type orthogonal frequency division multiplexing; carrier frequency synchronization method; demodulation; frame synchronization; frequency acquisition method; frequency offset; maximum correctable frequency range; maximum likelihood estimation; orthogonality; subcarriers; timing offset; wireless local area network; Demodulation; Detectors; Frequency estimation; Frequency synchronization; Maximum likelihood detection; Maximum likelihood estimation; Multilevel systems; OFDM; Timing; Wireless LAN;
Conference_Titel :
Consumer Electronics, 2001. ICCE. International Conference on
Conference_Location :
Los Angeles, CA
Print_ISBN :
0-7803-6622-0
DOI :
10.1109/ICCE.2001.935286
