Design of dual‐band leaky wave antenna based on microstrip to EH ₀ / EH ₁ ‐mode converter

In this work, a microstrip leaky-wave antenna (LWA) under EH0/EH1-mode excitations is proposed for dual-band application. By introducing periodic shorting pins in the microstrip line, the leaky wave regions of EH0 and EH1-mode are created in two operation bands respectively. According to the electric field distribution of EH0 and EH1-mode, the equal phase feeding network is constructed to excite EH0-mode, while the EH1-mode needs the excitation with opposite phase feeding. To satisfy this special phase requirement in two operation bands, a dual-mode converter is designed based on a one-wavelength-ring balun, which provides two passbands with equal/opposite phase operations. To validate this proposal, a prototype of this dual-band LWA is designed and fabricated. The measured results exhibit that the proposed antenna could radiate beams under EH0-mode in 4.2 GHz and EH1-mode in 6.3 GHz.