Synthesis of broadband 3D AMC ground planes using genetic programming

The development and use of genetic programming (GP) software to synthesize true-3D artificial magnetic conductor (AMC) ground planes is presented, with the focus on achieving a lower frequency response (particularly in the high VHF to low UHF bands), low-profile, broadband designs without the use of absorbing or magnetic materials. Metallic 3D patterns are embedded in one or more substrate layers with a PEC bottom, and the patterning in the unit cell is allowed to extend into neighboring unit cells, thus achieving a lower frequency response with much smaller unit cell size and thickness. Two designs synthesized using the developed GP software are presented with achieved bandwidths of 71.1% and 51.6% when using the ±90° reflection phase criterion.