Decision directed impulse noise mitigation for OFDM in frequency selective fading channels [DVB-T example]

• Published in: 2004 IEEE Global Telecommunications Conference - Globecom Vol. 6; pp. 3536 - 3540 Vol.6
• Main Authors: Armstrong, J., Suraweera, H.A.
• Format: Conference Proceeding
• Language: English
• Published: Piscataway, New Jersey IEEE 2004
• Subjects: Algorithm design and analysis; Analytical models; Applied sciences; Broadcasting. Videocommunications. Audiovisual; Demodulation; Detection, estimation, filtering, equalization, prediction; Digital TV; Digital video broadcasting; Error analysis; Exact sciences and technology; Fading; Information, signal and communications theory; Multiplexing; OFDM; Rayleigh channels; Signal and communications theory; Signal, noise; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Television; Transmission and modulation (techniques and equipments); TV broadcasting; Fading channels; Noise figure; Noise reduction; Digital television; Rayleigh channels; Error rate; Data transmission; Television applications; Rice fading; Cable television; Noise factor; Subcarrier; Algorithm; Digital transmission; Digital broadcasting; Pulse noise; Weighting; Frequency selection; Simulation; Orthogonal frequency division multiplexing; Signal processing; Demodulation
• ISBN: 9780780387942; 0780387945
• DOI: 10.1109/GLOCOM.2004.1379024

Impulse noise is a significant problem in some OFDM applications, including digital television broadcasting. In this paper, we study a novel decision directed impulse mitigation algorithm, both analytically and with simulations for the DVB-T parameters. In this algorithm, the noise component in each received input sample is estimated based on preliminary decisions on the transmitted data. When the estimate is large enough to indicate that impulse noise is present in the sample, the estimated noise component is subtracted from the input sample before final demodulation. This technique has been shown to be extremely effective in flat fading channels. In this paper, its application in frequency selective fading channels is analyzed. The optimum weighting factors for combining noise estimates from subcarriers subject to different fading are calculated. Simulation results are presented for Rayleigh and Ricean channels which show that the technique can reduce the error rates due to impulsive noise by an order of magnitude.