Detecting OFDM Signals in Alpha-Stable Noise

作者：Mahmood Ahmed^*; Chitre Mandar; Armand Marc Andre

来源：IEEE Transactions on Communications, 2014, 62(10): 3571-3583.

DOI：10.1109/TCOMM.2014.2351809

• OFDM
• impulsive noise
• AWS alpha SN
• ML
• M-estimation
• compressed sensing

This paper analyzes various receiver schemes for orthogonal frequency division multiplexing (OFDM) transmission in impulsive noise. We consider Rayleigh block-fading and model the noise process by additive white symmetric a-stable noise (AWS alpha SN). We begin by discussing maximum-likelihood (ML) detection performance of baseband OFDM. Though optimal, the computational cost increases exponentially with the number of carriers. Alternatively, one may evaluate soft-estimates of the transmitted symbol block and employ carrier-wise detection to lower computational complexity. We analyze such schemes under the frameworks of M-estimation and compressed sensing theory. Moving on, we highlight important rules that ensure the passband AWS alpha SN process is converted to a baseband form suitable for the discussed schemes. Finally, it is shown that linear passband-to-baseband conversion actually reduces the signal-to-noise ratio (SNR) at the receiver and that all these rules may be avoided by applying an estimation scheme directly on the passband samples.

• 出版日期2014-10