Doubly-selective channel estimation with unknown interference in OFDM systems

作者:Zhou, Jingrong*; Zhao, Sai; Tan, Yizhi; Qin, Jiayin
来源:Electronics Letters, 2016, 52(7): 521-522.
DOI:10.1049/el.2015.3668

摘要

In orthogonal frequency division multiplexing-based spectrum sharing networks, due to inefficient coordination or imperfect spectrum sensing, the signals from femtocells or secondary users appear as interference in a subset of subcarriers of the primary systems. For pilot-based doubly-selective channel estimation, the embedded pilots in pilot subcarriers would inevitably be harmed by the unpredictable interference. This unsolved issue is considered and proposed is a variational expectation maximisation-based method to iteratively learn the distribution of thermal noise plus interference, and refine doubly-selective channel estimates. Simulations demonstrated the superiority of the proposed approach over existing algorithms without considering interference mitigation.