Low-Complexity CFO Estimation for FBMC-Based Massive MIMO systems

In this paper, we propose a joint carrier frequency offset (CFO) and channel estimation scheme for multiuser filter bank multicarrier (FBMC) in the uplink of massive multiple-input multiple-output (MIMO) systems. Due to the large number of antennas at the base station (BS), CFO estimator can impose a substantial amount of computational burden to the system and its performance depends on the type of the training sequence being deployed. To address this issue, we propose a low-complexity CFO estimation technique using Hadamard matrix for training sequences. The proposed technique can estimate both integer and fractional CFO values without any limitation on the CFO acquisition range. Our solution is performed after combining the received signals from different antennas at the BS. Finally, we evaluate the efficacy of our proposed algorithm through numerical results.