An Independently Tunable Tri-Band Antenna Design for Concurrent Multiband Single Chain Radio Receivers

In this paper, a novel tunable tri-band antenna is presented for concurrent, multiband, and single chain radio receivers. The antenna is manufactured on a 50 100 mm FR4 printed circuit board, and is able to provide three concurrent, independently tunable operating bands covering a frequency range from 600 MHz to 2.7 GHz. The antenna performance is investigated for both numerical and experimental methods when using, first, varactor diodes and, second, digitally tunable capacitors (DTCs) to tune frequencies, which shows that the antenna gain can be improved by up to 2.6 dBi using DTCs. A hardware-in-the-loop test-bed provides a system level evaluation of the proposed antenna in a direct RF digitized, concurrent, and tri-band radio receiver. By measuring the receiver's error vector magnitude, we demonstrate sufficient isolation between concurrent bands achieving 30 MHz of aggregated bandwidth as well as strong resilience to adjacent blockers next to each band. The data reported in this paper are available from the ORDA digital repository (https://doi.org/10.15131/shef.data.5346295).