PREAMBLE-BASED FBMC/OQAM CHANNEL ESTIMATION WITHOUT GUARD SYMBOLS

Eleftherios Kofidis (1)

1 University of Piraeus

Intrinsic interference is known to present a challenge for signal processing tasks in systems employing offset quadrature amplitude modulation-based filter bank multicarrier (FBMC/OQAM) for transmission. In channel estimation, in particular, this otherwise called self interference will corrupt the pilot symbols, thus preventing accurate estimation, unless special means, such as inserting null guard symbols between the training and the information part, are employed, with a consequent loss in spectral efficiency. Iterative procedures that alternatingly estimate the channel and the interfering data symbols have been proposed to tackle this problem. In this pre-print, these are re-visited, emphasizing the most challenging case of channels of high frequency selectivity that has been studied very little in this respect. The approach followed here capitalizes on the analytical structure of the problem, providing closed-form expressions and efficient ways of computation, and is inspired by the analogy of the intrinsic interference with the interference between information and pilot symbols arising in superimposed training. Preamble-based estimation is considered, with both Gauss-Markov and linear minimum mean squared error (LMMSE) criteria, and no simplifying assumption is made on the relative (with the FBMC symbol duration) frequency selectivity of the channel. Simulation results with realistic channel models are reported and discussed.

Domaines: Traitement du signal et de l'image [eess.SP]

Eleftherios Kofidis. PREAMBLE-BASED FBMC/OQAM CHANNEL ESTIMATION WITHOUT GUARD SYMBOLS. 2020. ⟨hal-02889973⟩