Optimal Beampattern Synthesis of a Polarized Array

Utilizing the polarization information in waveforms about targets enables improving the performance of radar systems. We consider the optimal synthesis of the polarized beampattern of an array of antennas, each having two orthogonal electricdipole elements. We control the amplitudes and phases of the electric fields emitted from these dipole antennas to synthesize the electromagnetic beam with desired power and polarization patterns. The problem is formulated in a convex form which is thus efficiently solvable. We compare the performance of two synthesizing methods: (i) separate design of the two co-aligned dipole antenna sub-arrays; and (ii) joint design of the cross-dipole antenna array. Our results indicate that these two separate designs have the equivalent capability of suppressing the sidelobe power density, whereas the joint design has the additional advantage of controlling the beam polarizations. The results are also demonstrated by numerical examples.