Secure Array Synthesis

A new array synthesis problem, whose objective is to maximize secure information shared with a legitimate recipient in the presence of a passive eavesdropper, is posed for line-of-sight (LOS) wireless transmission. By casting the problem into the form of a semidefinite program, it is found that the problem is convex and that optimal solutions can be efficiently found irrespective of the array topology. Representative results for a uniform linear array (ULA) and uniform circular array (UCA) are presented to demonstrate the utility of the method. Furthermore, it is shown that the radiated power of the optimal solution can be naturally decomposed into a signal pattern and noise pattern, providing an intuitive description of the optimal solutions and allowing comparison with standard array synthesis techniques.