Title :
An improved channel estimator with real-time ISI free window tracking for OFDM systems
Author :
Zhou, Zhigang ; Cheng, Shixin ; Chen, Ming ; Wang, Haifeng
Author_Institution :
Nat. Mobile Commun. Res. Lab., Southeast Univ., Nanjing, China
Abstract :
An improved channel estimator with inter-symbol interference (ISI) free window measurement for OFDM systems is proposed by exploiting the inherent correlation between the cyclic prefix and portion of the received OFDM signal. This scheme make use of real time measured size of ISI free window to estimate the maximum delay spread of channel, then a transform domain channel estimator is adopted to further reduce the noise variance. Due to the ISI-free window can be estimated before the application of FFT to the received signal, it is a parallel processing, and very suitable for practical systems. Simulation result demonstrated that the proposed method can track the variation of delay spread of wireless channel, and improve the MSE of channel estimation significantly, thus give at least 1-db improvement in TU channel and 0.5-db in HT channel.
Keywords :
OFDM modulation; channel estimation; delays; fast Fourier transforms; intersymbol interference; mean square error methods; noise; parallel processing; radio networks; real-time systems; transceivers; OFDM system; channel estimation; fast Fourier transform; intersymbol interference; maximum delay spread; mean square error estimation; orthogonal frequency division multiplexing; real-time ISI free window tracking; wireless channel; Delay effects; Delay estimation; Intersymbol interference; Noise measurement; Noise reduction; OFDM; Parallel processing; Real time systems; Signal processing; Size measurement;
Conference_Titel :
Personal, Indoor and Mobile Radio Communications, 2004. PIMRC 2004. 15th IEEE International Symposium on
Print_ISBN :
0-7803-8523-3
DOI :
10.1109/PIMRC.2004.1368753
