A derivative of orthogonal frequency division multiplexing (OFDM) based on offset quadrature amplitude modulation, OFDM/OQAM, is among the waveform contenders for future wireless networks. Focusing on multiuser scenarios, i.e. uplink of a multiple access system, we propose an improved joint estimation method for carrier frequency offset, sampling time offset and channel impulse response needed for the practical application of OFDM/OQAM. The proposed method offers a pilot-based maximum-likelihood (ML) estimation of the unknown parameters in multiuser OFDM/OQAM systems. Formulation of the estimator is based on the splitting of each received pilot symbol into contributions from surrounding pilot symbols, non-pilot symbols, additive noise and multiuser interference. The proposed estimator is compared with a highly cited previous work of the same focus where the improvements in the results indicate the superiority of the former.
Ali Baghaki, B. Champagne
2018 IEEE Wireless Communications and Networking Conference (WCNC)