2D Periodic Leaky-wave Antenna with Circularly Polarized Property

A 2D circularly polarized periodic leaky-wave antenna with for microwave application is proposed. This antenna consists of a series of metal rings concentrically with additional periodic radial strips on the rings. A circularly-polarized patch antenna is designed as the feeding source, with a coaxial probe vertically excited. The surface wave around the central patch is then perturbed into a leaky-wave radiation, to produce two circularly-polarized conical beams. The impedance bandwidth of the proposed antenna with |S
11
| ≤ –10 dB is 24% ( from 7.4GHz to 9.4 GHz) and the 3-dB AR bandwidth is 21% ( from 7.7GHz to 9.4 GHz). The peak gain of the proposed antenna is 8.5dBi.