Microstrip Leaky-Wave Antenna With Circular Polarization and Broadside Radiation

In this letter, a novel circularly polarized microstrip leaky-wave antenna (LWA) is proposed with broadside radiation and high gain. A conventional microstrip patch has been modified to obtain broadside gain along with circular polarization. The modified patch is periodically placed along one side of the 50 Ω delay line to form LWA. The optimized broadside frequency of the antenna is 10.1 GHz. The bandwidth associated with 3 dB axial ratio is 13.3% while the maximum obtained gain is 15.8 dBic. The measured gain variation within 3 dB axial ratio bandwidth is 1.6 dB. Measured results of the fabricated antenna follow the simulations.