Compressed sensing techniques for receiver based post-compensation of transmitter's nonlinear distortions in OFDM systems

In this paper, compressed sensing techniques are proposed to linearize commercial power amplifiers driven by orthogonal frequency division multiplexing signals. The nonlinear distortion is considered as a sparse phenomenon in the time-domain, and three compressed sensing based algorithms are presented to estimate and compensate for these distortions at the receiver using a few and, at times, even no frequency-domain free carriers (i.e. pilot carriers). The first technique is a conventional compressed sensing approach, while the second incorporates a priori information about the distortions to enhance the estimation. Finally, the third technique involves an iterative data-aided algorithm that does not require any pilot carriers and hence allows the system to work at maximum bandwidth efficiency. The performances of all the proposed techniques are evaluated on a commercial power amplifier and compared. The error vector IThis work was supported by King Abdulaziz City for Science and Technology (KACST) through the Science & Technology Unit at King Fahd University of Petroleum & Minerals through Project No. 11-ELE1651-04 as part of the National Science, Technology and Innovation Plan. ∗Corresponding author. Tel.: +966-3-860-7394 Email addresses: [email protected] (Damilola S. Owodunni), [email protected] (Anum Ali), [email protected] (Ahmed A. Quadeer), [email protected] (Ebrahim B. Al-Safadi), [email protected] (Oualid Hammi), [email protected] (Tareq Y. Al-Naffouri) Preprint submitted to Elsevier magnitude and symbol error rate results show the ability of compressed sensing to compensate for the amplifier’s nonlinear distortions.