  We develop sparse array receive beamformer design methods achieving maximum
signal-to-interference plus noise ratio (MaxSINR) for wideband sources and
jammers. Both tapped delay line (TDL) filtering and the DFT realizations to
wideband array processing are considered. The array sparsity stems from the
limited number of available RF transmission chains that switch between the
sensors, thereby configuring different arrays at different times. The sparse
array configuration design problem is formulated as a quadratically constraint
quadratic program (QCQP) and solved by using SDR (semidefinite relaxation). A
computationally viable approach through SCA (successive convex relaxation) is
also pursued. In order to realize an implementable design, in presence of
missing autocorrelation lags, we propose parameter-free block Toeplitz matrix
completion to estimate the received data correlation matrix across the entire
array aperture. It is shown that the optimum wideband sparse array effectively
utilizes the array aperture and provides considerable performance improvement
over suboptimal array topologies.
