S-band dual-path dual-polarized antenna system for satellite digital audio radio service (SDARS) application

This paper presents a novel compact dual-polarized antenna system for S-band satellite digital broadcasting receivers. The demonstrated antenna system consists of a low form factor dual-polarized antenna pair and two-stage low-noise amplifiers (LNAs) integrated with each antenna. One antenna is a low-profile annular ring patch antenna having a 90° phase-delay element for circular polarization (CP) and the other antenna is a reactively-loaded monopole antenna for linear polarization (LP). Both antennas operate in the same frequency range, from 2.320 to 2.345 GHz, while providing different polarizations to take advantage of the polarization diversity. Switches are used to select the mode (polarization) of operation. This ensures that appropriate dc bias is supplied to the operating LNA to process the received signal while no power is consumed by the idle LNA. The measured gains of the antenna system are 31.3 and 21.9 dBi for the CP and LP modes, respectively.