The feasibility of blind channel estimation without the aid of any pilot-training symbols is investigated for the HomePlug power-line standard. This standard uses orthogonal frequency-division multiplexing (OFDM) and a custom windowing function for the purposes of spectral shaping. The latter feature makes blind channel estimation a difficult challenge. Theoretical and simulation results demonstrate that blind channel estimation is possible, however, through the exploitation of certain HomePlug standard signal features and eigenvalue decomposition. It should be noted that this paper is not a comparison of various channel estimation techniques (i.e., trained versus semiblind versus blind), but an assessment of 1) whether a blind estimation technique is feasible with the HomePlug power-line standard and 2) to determine its effectiveness in a typical power-line setting.
https://www.ece.unb.ca/petersen/pubs/DiMePe11/