A compact, wideband, planar filtenna with reconfigurable tri-polarization diversity is presented. The operating mechanisms of its bandpass filter and its bandwidth enhancement are explained through a step-by-step design evolution. Its feed network consists of three J-shaped probes, a Wilkinson power divider, and phase shifters. Reconfigurability is achieved by integrating four pairs of p-i-n (PIN) diodes into it. Three polarization-reconfigurable states: linear polarization (LP), left-hand circular polarization (LHCP), and right-hand circular polarization (RHCP), are dynamically controlled by those PIN diode switches. A prototype was fabricated, assembled, and tested, which has a compact size (0.48 λ0 × 0.45 λ0) and is low profile (0.096λ0). The measured results, in good agreement with their simulated values, demonstrate that the filtenna has a wide -10-dB impedance bandwidth (|S11| ≤ -10 dB) of 15.6%, which completely encompasses the axial ratio (AR) bandwidths (AR ≤ 3 dB) of the two circular polarization (CP) states. The realized gain values over this bandwidth: 7.7 ± 0.5 dBi, are very stable for all three dynamical states. Furthermore, the filtenna exhibits good out-of-band rejection performance characteristics.
- planar antennas
- polarization diversity
- reconfigurable antennas
ASJC Scopus subject areas
- Electrical and Electronic Engineering