Bi-directional active and passive meandered circularly polarized CRLH-inspired leaky-wave antennas based on substrate integrated waveguide

Bi-directional active and passive meandered circularly polarized (CP) composite right/left-handed (CRLH) inspired substrate integrated waveguide (SIW) based leaky-wave antennas (LWAs) are presented. By meandering the microstrip line, the dimension of the proposed five-cell antenna along the scanning plane is reduced by 33.5% compared to the original CP CRLH LWA based on SIW [1]. Furthermore, incorporating the bi-directional amplifiers, the current distribution of the antenna is manipulated to control the radiation characteristics. The proposed active meandered CP CRLH LWA supports both transmitting and receiving operation while delivering enhanced spatial resolution.