Multiport compact stacked patch antenna with 360° beam steering for generating dynamic directional modulation

In this contribution, we propose a multiport compact antenna that supports four radiating modes operating at the same frequency thus making it a suitable candidate to substitute a linear array of four antennas. It will be also shown as this antenna produces dynamic directional modulation (DDM) with low bit error rate (BER) in a unique, unambiguous (secure) angular region that can be chosen freely in the XY plane. Trade-offs between the BER beam width of the secure angular region, the BER at side lobes and the extra power required in the generation of DDM are assessed through measurements with real-time data transmission.