Doppler spread estimation for wireless OFDM systems

Author

Yucek, Tevfik ; Tannious, Ramy M A ; Arslan, Huseyin

Author_Institution

Dept. of Electr. Eng., Univ. of South Florida, Tampa, FL

fYear

2005

fDate

18-19 April 2005

Firstpage

233

Lastpage

236

Abstract

We present a method for estimating the Doppler spread in mobile orthogonal frequency division multiplexing (OFDM) systems. The estimation is based on finding the autocorrelation function of time domain channel estimates over several OFDM symbols. In OFDM systems, channel estimation is popularly performed in the frequency domain. Channel frequency response estimates are affected by noise and intercarrier interference (ICI). As a result, Doppler estimates based on frequency domain channel estimates are affected significantly. We show that the use of channel estimates in the time domain can greatly improve the performance of Doppler estimates. The channel impulse response (CIR) can be obtained by taking the IDFT of the channel frequency response (CFR). Consequently, the proposed method reduces processing time and memory usage. Computer simulations support our claim for a broad range of Doppler spread and signal-to-noise ratio (SNR) values in Rayleigh fading channels

Keywords

Doppler broadening; OFDM modulation; Rayleigh channels; channel estimation; correlation methods; discrete Fourier transforms; frequency response; mobile radio; radiofrequency interference; random noise; time-domain analysis; transient response; Doppler spread estimation; ICI; Rayleigh fading channels; SNR; autocorrelation function; channel frequency response estimation; channel impulse response; frequency domain channel estimation; intercarrier interference; inverse DFT; mobile OFDM systems; mobile orthogonal frequency division multiplexing systems; noise; signal-to-noise ratio; time domain channel estimation; wireless OFDM systems; Autocorrelation; Channel estimation; Computer simulation; Fading; Frequency domain analysis; Frequency estimation; Frequency response; Interference; OFDM; Signal to noise ratio;

fLanguage

English

Publisher

ieee

Conference_Titel

Advances in Wired and Wireless Communication, 2005 IEEE/Sarnoff Symposium on

Conference_Location

Princeton, NJ

Print_ISBN

0-7803-8854-2

Type

conf

DOI

10.1109/SARNOF.2005.1426552

Filename

1426552