  The self-equalization property has raised great concern in the combination of
offset-quadratic-amplitude-modulation-based filter bank multi-carrier
(FBMC/OQAM) and massive multiple-input multiple-output (MIMO) system, which
enables to decrease the interference brought by the highly frequency-selective
channels as the number of base station (BS) antennas increases. However,
existing works show that there remains residual interference after single-tap
equalization even with infinite number of BS antennas, leading to a limitation
of achievable signal-to-interference-plus-noise ratio (SINR) performance. In
this paper, we propose a two-stage design scheme of equalizers to remove the
above limitation. In the first stage, we design high-rate equalizers working
before FBMC demodulation to avoid the potential loss of channel information
obtained at the BS. In the second stage, we transform the high-rate equalizers
into the low-rate equalizers after FBMC demodulation to reduce the
implementation complexity. Compared with prior works, the proposed scheme has
affordable complexity under massive MIMO and only requires instantaneous
channel state information (CSI) without statistical CSI and additional
equalizers. Simulation results show that the scheme can bring improved SINR
performance. Moreover, even with finite number of BS antennas, the interference
brought by the channels can be almost eliminated.
