Robust Frequency Offset Estimation of OFDM Systems
Date Issued
2005
Date
2005
Author(s)
Sun, Kin-Man
DOI
en-US
Abstract
OFDM, in spite of being sensitive to interference, is widely applied in wireless broadband communications. The effect of preamble symbol aided timing and frequency offset estimation in the presence of narrowband interference is investigated. Time-frequency interleaving OFDM has been generally considered for ultra-wide band communications, which must operate under (relatively) narrow-band interferences. By mitigation with the aid of time-frequency interleaving, we develop effective frequency offset estimation under interference in this thesis. Applying adaptive noise cancellation and frequency domain transformation technique, both time-domain and frequency-domain algorithms to estimate frequency offset via correlating samples and correlating subcarriers respectively of repeated preamble symbols from different sub-bands are shown robust to interference in OFDM systems. It can be shown that frequency-domain approach is much robust than time-domain approach when preamble symbol are affected by severe NBI over all sub-bands since the error floor effect is suppressed much efficiently at high SNR region.
Subjects
頻率偏移估測
正交分頻多工
窄頻干擾
時頻交錯
超寬頻
frequency offset estimation
orthogonal frequency division multiplexing (OFDM)
narrowband interference (NBI)
time-frequency interleaving (TFI)
ultra-wideband (UWB)
Type
thesis