Open Stopband Suppressed, Gain Flatness Enhanced, and Cross-Polarization Reduced Leaky-Wave Antenna Using High-Order Mode Substrate Integrated Cavity

Lei, Peng and Yan, Zhenggang and Liao, Zhangqi and Zhang, Meng and Lu, Wenzhong and Wang, Xiao-Chuan and Wei, Changning and Wang, Lei (2025) Open Stopband Suppressed, Gain Flatness Enhanced, and Cross-Polarization Reduced Leaky-Wave Antenna Using High-Order Mode Substrate Integrated Cavity. IEEE Transactions on Antennas and Propagation. ISSN 0018-926X

Text (Open_Stopband_Suppressed__Gain_Flatness_Enhanced__and_Cross_Polarization_Reduced_Leaky_Wave_Antenna5_Final_R2_ (1))
Open_Stopband_Suppressed_Gain_Flatness_Enhanced_and_Cross_Polarization_Reduced_Leaky_Wave_Antenna5_Final_R2_1_.pdf - Accepted Version
Available under License Creative Commons Attribution.
Download (11MB)

Abstract

A novel high-order mode substrate integrated cavity leaky-wave antenna (LWA) with high gain, low cross-polarization, and continuous beam scanning is proposed. The proposed antenna element employs mirror-symmetric arc-shaped slots within a circular substrate integrated cavity (CSIC), fed by a grounded coplanar waveguide. Moreover, the high-order TM110 mode of CSIC is employed to form an equivalent two-element array, enhancing element directivity and beam scanning capability. Unlike conventional LWAs, the proposed LWA achieves wide scanning and gain flatness enhanced by utilizing element-level beam scanning. Additionally, the open stopband is suppressed through impedance tuning of the arc-shaped slots, without degrading polarization purity. Experimental results demonstrate that the proposed LWA achieves a beam scanning range of –78° to 28° within a frequency range of 6.7 to 13 GHz, with a maximum gain of 17.3 dBi at 11 GHz, a peak radiation efficiency of 91%, and a cross-polarization ratio exceeding 45 dB.