碩士 / 國立暨南國際大學 / 電機工程學系 / 93 / Orthogonal frequency division multiplexing (OFDM) technique is
effective and powerful in high data rate digital transmission due
to its spectral efficiency, robustness in multipath propagation
environments and ability to cope with inter-symbol interference
(ISI). Channel estimation is a crucial problem in coherent OFDM
systems and system performance based on particular pilot
arrangement is investigated recently.
In this Thesis, a two-dimensional channel estimation technique is
developed for wireless OFDM communications under
frequency-selective fading channels. The channel types are chosen
as COST 207. Different delay spreads are compared. The proposed
algorithm is based on the conventional one-dimensional channel
estimation schemes and the pilot arrangements. By using
two-dimensional pilot arrangement, channel information can be
obtained in both two domains.
By applying least-square (LS) estimation for the leading pilot
symbol in time domain, the channel statistics can be obtained and
preserved. And then, LS is also applied for the following regular
pilot tones in the OFDM data symbol. Based on the variation of
these two LS estimates in the time domain, a novel two-dimensional
channel estimation algorithm is presented. From the simulation
results, the proposed channel estimation scheme has significant
performance in the severe frequency-selective fading channels,
especially in high SNR. Even if the mobile speed rises, the
proposed algorithm still achieves excellent performance. Moreover,
the proposed algorithm can be operated on-line.
| Identifer | oai:union.ndltd.org:TW/093NCNU0442083 |
| Creators | Chien-Yu Huang, 黃建渝 |
| Contributors | 林容杉 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 58 |
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