Sparsity and Rank Exploitation for Time-Varying Narrowband Leaked OFDM Channel Estimation

Amr Elnakeeb; Urbashi Mitra

ICASSP 2018accepted0 citations

Sparsity and Rank Exploitation for Time-Varying Narrowband Leaked OFDM Channel Estimation

Abstract

In this paper, the problem of time-varying narrowband leaked Orthogonal Frequency Division multiplexing (OFDM) channel estimation is considered. The leakage effect results from practical constraints on communication systems: finite bandwidth and block length. These practical constraints effectively render a sparse channel into a non-sparse one. The inherent low-rank structure of the received signal, determined by the number of dominant paths of the channel, is exploited. The current work extends prior work on single carrier systems to OFDM; herein, it is also known that leaked OFDM channel is separable in delay and Doppler domains. A convex optimization approach, based on the atomic norm heuristic, is developed. Optimality and uniqueness of the proposed channel estimation method are shown. Simulation results show superiority over the classical l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> element-wise sparse method with an average 8 dB improvement.

BibTeX

@inproceedings{icassp2018_sparsityandranke,
  title = {Sparsity and Rank Exploitation for Time-Varying Narrowband Leaked OFDM Channel Estimation},
  author = {Amr Elnakeeb and Urbashi Mitra},
  booktitle = {ICASSP 2018},
  year = {2018}
}