Research
Problem:
Frame/Symbol synchronization for IEEE
802.11a (OFDM-based) WLANs
Description:
OFDM is
employed as the transmission technique
in the IEEE 802.11a WLAN standard. Frame synchronization in OFDM
systems
is very important since misalignment of the frame position leads to
severe
ISI. In the IEEE 802.11a standard, a preamble is dedicated to
various
synchronization tasks. However, there is no mention in the
standard how
to use the preamble to achieve synchronization. In this study, we
developed a wide range of frame synchronization algorithms for IEEE
802.11a
WLANs that outperform the existing state-of-the-art algorithms in terms
of
performance, complexity and robustness to multipath.
Representative Publications:
Yik-Chung Wu, Kun-Wah
Yip, Tung-Sang Ng and E.
Serpedin, ``Maximum-Likelihood Symbol Synchronization for IEEE 802.11a
WLANs
on Unknown Frequency-Selective Fading Channels,'' IEEE Trans. on
Wireless Communications, vol. 4, no. 6, pp.2751-2763, Nov. 2005. [PDF]
Kun-Wah Yip, Yik-Chung Wu and
Tung-Sang Ng,
“Timing-synchronization analysis for IEEE 802.11a wireless LANs in
frequency-nonselective Rician fading environments,” IEEE
Transactions on Wireless Communications, vol. 3, no. 2, pp.387-394,
Mar. 2004. [PDF]