Leaky-wave antenna with continuous backward-to-forward frequency scanning using strip-fed cavity-backed slots

Abstract

A leaky-wave antenna made of cavity-backed-slot radiating elements with open-stopband suppression is presented. The cavity-backed slots are seriesly fed by a strip. The bandwidth of the unit cell of the array is enhanced by a recently-proposed technique that uses a matching stub. The open-stopband effect is mitigated by misaligning the stub with respect to the slot. An array is designed and fabricated. The array is built using an aluminum set of cavities filled with 3D printed material to support the substrate where the feed and slots are etched. The measurement of the prototype shows the overall good performance of the array. The array is able to scan its beam from $-{70}^{\circ }$ to 50${}^{\circ }$ in the 2.8–4.4 GHz frequency range, keeping good matching even at the broadside frequency. The gain is stable over the band.

Keywords:

• Broadside radiation
• cavity-backed slot
• frequency beam scanning
• leaky-wave antenna
• open stopband

Acknowledgments

The authors would like to thank Prof. J. Esteban, from Universidad Politécnica de Madrid (Spain), for helping with the measurement of the array and J. M. Romero-Romero for fabricating the 3D-printed material.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Spanish Ministerio de Educación, Cultura y Deporte (Programa para la Formación del Profesorado Universitario) under grant FPU15/06457, by the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIU), the Agencia Estatal de Investigación (AEI) and the Fondo Europeo de Desarrollo Regional (FEDER) (Programa Estatal de I+D+i Orientada a los Retos de la Sociedad) under grant RTI2018-097098-J-I00, and by the regional government, Junta de Andalucía, Plan Andaluz de Investigación, under grant PY20_00452.