  In this paper, we consider how the uplink transmission of a spatially
correlated massive multiple-input multiple-output (MIMO) system can be
protected from a jamming attack. To suppress the jamming, we propose a novel
framework including a new optimal linear estimator in the training phase and a
bilinear equalizer in the data phase. The proposed estimator is optimal in the
sense of maximizing the spectral efficiency of the legitimate system attacked
by a jammer, and its implementation needs statistical knowledge about the
jammer's channel. We derive an efficient algorithm to estimate the jamming
information needed for the implementation of the proposed framework.
Furthermore, we demonstrate that optimized power allocation at the legitimate
users can improve the performance of the proposed framework regardless of the
jamming power optimization. Our proposed framework can be exploited to combat
jamming in scenarios with either ideal or non-ideal hardware at the legitimate
users and the jammer. Numerical results reveal that using the proposed
framework, the jammer cannot dramatically affect the performance of the
legitimate system.
