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A Design of IFFT Processor for Reducing OFDM Transmitter Latency  

Kim, Jun-Woo (한국전자통신연구원 이동단말모뎀연구팀)
Park, Youn-Ok (한국전자통신연구원 이동단말모뎀연구팀)
Kim, Whan-Woo (충남대학교 전자전파정보통신공학과)
Publication Information
The Journal of Korean Institute of Communications and Information Sciences / v.34, no.12C, 2009 , pp. 1167-1176 More about this Journal
Abstract
In This Paper, we introduce an efficient IFFT design technique named for transmitter of OFDM (Orthogonal Frequency Division Multiplexing) system. In OFDM system, a cyclic prefix is inserted in forepart of OFDM symbol to prevent ICI(Inter-channel Interference) and ISI (Inter-symbol Interference). Attaching cyclic prefix causes delay in storing and copying IFFT result. The proposed IFFT removes this delay because its output is cyclic shifted by the length of cyclic prefix. So we can make a complete OFDM symbol by just copying the forepart of IFFT output to the end. In many cases, the length of cyclic prefix is 1/2n of FFT size, and this IFFT does not require additional hardware complexity and it does not cause any performance degradation.
Keywords
IFFT; FFT; OFDM; CP; Cyclic Prefix;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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