Single-pin dual-band patch antenna for GPS and SDARS applications

A novel low-cost reduced-size single-feed single-layer microstrip patch antenna is presented that receives right-hand circularly polarized satellite signals for the Global Positioning System´s L1-Band (1575.42 MHz) and left-hand circularly polarized satellite signals and vertically linearly polarized terrestrial signals for the Satellite Digital Audio Radio System band (2320 MHz - 2345 MHz). The proposed antenna is constructed of a main central patch and a ring surrounding it, both with truncated corners to achieve the desired circular polarization characteristics. The two patches are connected to each other using 4 long and thin microstrip transmission lines. This antenna has acceptable circularly polarized gain at high elevation angles and acceptable vertically linearly polarized gain at the horizon.