Title :
Time-variant distortions in OFDM
Author :
Stantchev, Branimir ; Fettweis, Gerhard
Author_Institution :
Dept. of Electr. Eng., Tech. Univ. Dresden, Germany
Abstract :
We analyze the degradation of orthogonal frequency division multiplexing (OFDM) signals from time-variant distortions like carrier and sampling frequency offset, Doppler spread and oscillator phase noise. We propose a novel analytical framework in the discrete-time domain based on the FFT demodulation of a single OFDM symbol and unify previous methods with some new results. Exact definitions of the signal-to-subcarrier-interference ratio (SIR) and the effective signal-to-noise ratio (SNR) are given and evaluated for a HIPERLAN/2 system.
Keywords :
Doppler effect; OFDM modulation; demodulation; fading channels; fast Fourier transforms; multipath channels; phase noise; radiofrequency interference; signal sampling; time-domain analysis; wireless LAN; Doppler spread; FFT demodulation; HIPERLAN/2 system; OFDM signal degradation; SIR; SNR; carrier frequency offset; discrete-time domain analysis; multipath fading channel; orthogonal frequency division multiplexing; oscillator phase noise; sampling frequency offset; signal-to-noise ratio; signal-to-subcarrier-interference ratio; time-variant distortions; Degradation; Demodulation; Fading; Intersymbol interference; OFDM; Phase distortion; Phase modulation; Phase noise; Sampling methods; Signal to noise ratio;
Journal_Title :
Communications Letters, IEEE
DOI :
10.1109/4234.880819
