A Low-profile and Low H-plane Cross Polarization Filter Shorted Patch Antenna with High Selectivity Design a novel filter SPA

A novel filter antenna with low H-plane cross-polarization(cross-pol) and high selectivity is proposed using single slot and three shorting pins integrated into low profile shorted-patch antenna (SPA). Initially, the modes TM1,5/2 and TM3,1/2 have been excited in the low profile SPA, with low H-plane cross-pol. Then, the two transmission zeros (TZs) can be obtained through the exist of the only one slot. After that, with the help of the three shorting pins, the frequency of the TM3,1/2 has been increased and the upper suppression has been improved. Then, the slot length and the width of the slot are utilized for a good impedance matching. In this paper, the H-plane cross-pol can reach below -50dBi, meanwhile, its gain in frequency band is 6 dBi above. What's more, the low-profile property has been obtained with the height of 0.011 free-space wavelength.