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arXiv · 1001.2298

Turbo Receiver Design for Phase Noise Mitigation in OFDM Systems

Gokul Sridharan·Teng Joon Lim
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Abstract

This paper addresses the issue of phase noise in OFDM systems. Phase noise (PHN) is a transceiver impairment resulting from the non-idealities of the local oscillator. We present a case for designing a turbo receiver for systems corrupted by phase noise by taking a closer look at the effects of the common phase error (CPE). Using an approximate probabilistic framework called variational inference (VI), we develop a soft-in soft-out (SISO) algorithm that generates posterior bit-level soft estimates while taking into account the effect of phase noise. The algorithm also provides an estimate of the phase noise sequence. Using this SISO algorithm, a turbo receiver is designed by passing soft information between the SISO detector and an outer forward error correcting (FEC) decoder that uses a soft decoding algorithm. It is shown that the turbo receiver achieves close to optimal performance.

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Gokul Sridharan, Teng Joon Lim. 2010-01-13. Turbo Receiver Design for Phase Noise Mitigation in OFDM Systems. https://arxiv.org/abs/1001.2298

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