講演抄録/キーワード |
講演名 |
2014-12-19 10:15
Proposal of Channel Estimation Method for Uplink OFDMA System under Time-varying Fading Environments ○Tanairat Mata・Mio Hourai(Mie Univ.)・Pisit Boonsrimuang(KMITL)・Kazuo Mori・Hideo Kobayashi(Mie Univ.) RCS2014-254 |
抄録 |
(和) |
Orthogonal Frequency Division Multiple Access (OFDMA) is considered as one of promising wireless communications techniques which can accommodate multiple users efficiently. In uplink OFDMA system, it is required to estimate all users? channel links simultaneously at base station (BS). To solve this problem, although the conventional Discrete Fourier Transform (DFT) interpolation-based channel estimation (DFTI-CE) method was proposed for uplink OFDMA system, the estimation accuracy of DFTI-CE method would be degraded when null subcarriers (zero padding) are added at both end of data subcarriers to reject the aliasing occurring at the output of D/A converter. In other words, the sampling rate for OFDM signal at the transmitter is taken by the non-Nyquist sampling in which the number of data subcarriers is not equal to the number of IFFT points. To solve this problem, this paper proposes a new time-domain channel estimation (TD-CE) method which can achieve higher estimation accuracy even at non-Nyquist sampling. The salient feature of proposed TD-CE method is to enable the estimation of all users' channel links simultaneously at the BS by using one common preamble symbol. This paper presents various simulation results to demonstrate the effectiveness of proposed estimation method. |
(英) |
Orthogonal Frequency Division Multiple Access (OFDMA) is considered as one of promising wireless communications techniques which can accommodate multiple users efficiently. In uplink OFDMA system, it is required to estimate all users? channel links simultaneously at base station (BS). To solve this problem, although the conventional Discrete Fourier Transform (DFT) interpolation-based channel estimation (DFTI-CE) method was proposed for uplink OFDMA system, the estimation accuracy of DFTI-CE method would be degraded when null subcarriers (zero padding) are added at both end of data subcarriers to reject the aliasing occurring at the output of D/A converter. In other words, the sampling rate for OFDM signal at the transmitter is taken by the non-Nyquist sampling in which the number of data subcarriers is not equal to the number of IFFT points. To solve this problem, this paper proposes a new time-domain channel estimation (TD-CE) method which can achieve higher estimation accuracy even at non-Nyquist sampling. The salient feature of proposed TD-CE method is to enable the estimation of all users' channel links simultaneously at the BS by using one common preamble symbol. This paper presents various simulation results to demonstrate the effectiveness of proposed estimation method. |
キーワード |
(和) |
uplink OFDMA / Zero-padding / non-Nyquist sampling / DFTI-CE / TD-CE / / / |
(英) |
uplink OFDMA / Zero-padding / non-Nyquist sampling / DFTI-CE / TD-CE / / / |
文献情報 |
信学技報, vol. 114, no. 372, RCS2014-254, pp. 201-206, 2014年12月. |
資料番号 |
RCS2014-254 |
発行日 |
2014-12-11 (RCS) |
ISSN |
Print edition: ISSN 0913-5685 Online edition: ISSN 2432-6380 |
著作権に ついて |
技術研究報告に掲載された論文の著作権は電子情報通信学会に帰属します.(許諾番号:10GA0019/12GB0052/13GB0056/17GB0034/18GB0034) |
PDFダウンロード |
RCS2014-254 |
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