Channel Impulsive Noise Mitigation for Linear Video Coding Schemes

This paper considers the problem of impulse noise mitigation for videos encoded using a SoftCast-based Linear Video Coding (LVC) scheme and transmitted using an OFDM scheme over a wideband channel prone to impulse noise. In the time domain, the impulse noise is modeled as realizations of iid Bemoulli-Gaussian variables. A Fast Bayesian Matching Pursuit algorithm is employed for impulse noise mitigation. This approach requires the provisioning of some OFDM subchannels to estimate the impulse noise locations and amplitudes. Provisioned subchannels cannot be used to transmit data and lead to a decrease of the nominal decoded video quality at receivers in absence of impulse noise. Using a phenomenological model (PM) of the residual noise variance after impulse correction, an algorithm is proposed to evaluate the optimal number of subchannels to provision for impulse noise mitigation. Simulation results show that the PM can accurately predict the number of subchannels to provision and that impulse noise mitigation can significantly improve the decoded video quality compared to a situation where all subchannels are used for data transmission.