A Dual-polarization Self-Duplex Antenna with High Isolation and Low Profile

A dual-polarization self-duplex antenna is proposed. When port 1 is excited, two half-modes (HM) resonances having similar radiation performance are produced by a slotted HM substrate integrated waveguide(HMSIW) cavity, which is also used to coupled feed the radiation patch, and a good operation band of port 1 is obtained. For obtaining the other operation band, the radiation patch is coupled fed by port 2 to excite two dipole resonant modes. The high port-to-port isolation is mainly resulted from the orthogonal polarization of the two ports and the high pass filtering response of HMSIW. The two operation bands can be tuned independently, they can work at different frequencies with isolation ≥ 54 dB, and also can work at overlapping frequencies with isolation of 47 dB, so the proposed self-duplex antenna can satisfy the requirements of in-band or different-band duplex application. The proposed antenna with low profile of 0.07λ0 is prototyped and experimentally verified, exhibiting two operation bands of 5.1–6.0GHz and 4.35–5.03GHz