  Phased arrays in near-field communication allow the transmitter to focus
wireless signals in a small region around the receiver. Proper focusing is
achieved by carefully tuning the phase shifts and the polarization of the
signals transmitted from the phased array. In this paper, we study the impact
of polarization on near-field focusing and investigate the use of dynamic
polarization control (DPC) phased arrays in this context. Our studies indicate
that the optimal polarization configuration for near-field focusing varies
spatially across the antenna array. Such a spatial variation motivates the need
for DPC phased arrays which allow independent polarization control across
different antennas. We show using simulations that DPC phased arrays in the
near-field achieve a higher received signal-to-noise ratio than conventional
switched- or dual-polarization phased arrays.
