This paper presents a modular substrate-integrated waveguide (SIW) antenna array based on H-plane aperture structures for Ka-band. The unitary antenna is based on a SIW aperture antenna with an improved H-plane radiation pattern by means of the implementation of metallic vias in the wave propagation along the H-plane antenna. The inner metallic vias are introduced to form four different sub-apertures at the end of the H-plane aperture antenna, dividing the field from the feeding into four in-phase wavefronts. In that manner, a flatter wavefront is generated to achieve high directivity. Additionally, some periodic parallel strips are printed at the end of the antenna aperture to improve the impedance matching with the air. The Hplane antenna is used as the constituting element for an E-plane array antenna, using four H-plane elements. The E-plane array antenna increases the antenna directivity, providing a pencil-shape beam, based on a series coaxial feeding structure. This feeding strategy favours the antenna modularity at the expense of suffering from a slight beam steering with frequency in the working bandwidth. The proposed antenna has an impedance matching below-10 dB from 32.9 to 37.0 GHz (equivalent to 11.73% bandwidth) with a nearly stable gain of almost 10 dBi for the H-plane unitary element and 14 dBi for the E-plane array. Prototypes of both antennas are manufactured to validate the proposed unitary antenna and array designs.
This paper presents a cavity-backed antenna array in substrate integrated waveguide (SIW) technology in the millimeter-wave frequency band. The proposed antenna design uses double slots as radiating elements instead of conventional single slots. The double slots allow better control in the design of the operating frequency bands of the cavity-backed antenna. The performance of the cavity-backed antennas with single and double slots is compared to assess the enhanced behavior of the double slots. As a proof of concept, a 2 × 2 array of cavity-backed antennas is designed, manufactured, and measured. Each cavity-backed antenna contains 2 × 2 double slots; thus, a 4 × 4 antenna array is considered. The experimental operating frequency band of the proposed antenna array ranges from 35.4 to 37 GHz. There is a good agreement between the simulated and measured results. The measured gain is around 17 dBi in the whole operating frequency band with a 75% total antenna efficiency.
This communication presents the design of a two-port electronically tunable phase shifter at K band. The phase shifter consists of a 3 dB hybrid coupler loaded with reflective phase-controllable circuits. The reflective circuits are formed by varactors and non-sequential impedance transformers which increase the operational bandwidth and the provided phase shift. The final phase shifter design is formed by two loaded-coupler stages of phase shifting to guarantee a complete phase turn. An 18 GHz phase shifter design with dynamic range of 600 degrees of phase shift is depicted in this document. The prototype is manufactured and validated through measurements showing good agreement with the simulation results.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.