Experimental Demonstration of Antenna Isolation Improvement using Planar Resonant Absorbers

Antenna isolation improvement using two different setups is experimentally demonstrated. Three resonant absorbers, which have been initially fabricated and characterized as free space absorbers, are inserted between pairs of horn and monopole antennas. The goal is to improve the isolation between those pairs and compare which absorber performs better in terms of bandwidth and isolation improvement. All absorbers have a similar surface dimension of 25.6 cm × 25.6 cm. The ultra-thin absorber, which is a narrow band free space absorber, improves the isolation in a narrow band, too. So, it is only effective to improve the isolation of a pair of narrow band antennas. The magnetic sheet and the dielectric resonator absorber cover the whole X-band as free space and also surface wave absorbers. The latter has the best isolation improvement within this band with an average of 23 dB for the horn setup and 19 dB for the monopole setup.