This study proposes a compact dual‐polarised directive radiator whose complex prototyping is enabled by additive manufacturing. In addition to monolithic implementation, stereolitography followed by metal coating, it also provides high radio‐frequency performance, low cost and low weight. Dual‐channel simultaneous operation is supported thanks to the integration of an orthomode transducer within the structure. Entirely waveguide based, this compound radiating structure is specially well suited to be 3D‐printed, and in principle, it allows scaling to match a specific frequency of operation. Both the antenna concept and the employed advanced manufacturing technique are validated experimentally through the realisation and measurement of two prototypes operating, respectively, at 30 and 60 GHz. The proposed architecture is easily amenable to be grouped in a compact higher‐gain array, thus holding strong potential for platform‐constrained applications, such as inter‐satellite links between CubeSats.

This article investigates the potential of additive manufacturing for the fabrication of complex antenna geometries with enhanced performance at K-band. Stereolithography is here used to 3D-print a novel topology of dual-polarized leaky-wave antenna that allows for the control of its aperture illumination both in phase and magnitude. The antenna consists of a modulated triple-ridge square waveguide perforated on its top wall with crossed slots of different sizes. An orthomodetransducer is integrated within the structure for dual-mode operation. Monolithic implementation of this compound threedimensional structure is only possible thanks to additive manufacturing. In addition, low weight and compactness are attained comparing to classical milling. The present proposal is validated through the manufacturing of a low sidelobe levels prototype suitable for intersatellite links. The corresponding measured results are in very good agreement with full-wave predictions.

A dual-band periodic structure is here proposed, which allows for versatile frequency selectivity and polarization conversion functionality. The structure is a monolithic fullmetal piece, and it is built from the arrangement of unit-cells consisting of waveguide sections at cutoff loaded with compound perforations. The topology of such unit-cells enables the efficient and independent interaction with vertical and horizontal electric field components illuminating the periodic structure. A circuit model is proposed to characterize the cells and understand their behaviour. Three different examples of cells are designed to illustrate the structure versatile functionality. One of these examples is manufactured, consisting of a dual-band structure that converts linear polarization into circular with orthogonal senses of rotation at each band. The experimental results are in good agreement with the theoretical predictions, thus validating the underlying operation mechanism and its practical feasibility.

In this letter, the design of a compact high-power waveguide low-pass filter with low insertion loss, all-higher order mode suppression, and stopband rejection up to the third harmonic, intended for Ka-band satellite applications, is presented. The method is based on step-shaped bandstop elements separated by very short (ideally of zero length) waveguide sections easily manufactured by low-cost computer-controlled milling. Matching is achieved by short input/output networks based on stubs whose heights are optimized following classical approaches. The novel filter presents a reduction in insertion loss and a remarkable increase in the high-power handling capability when compared to the classical waffle-iron filter and alternative solutions previously proposed, while the out-of-band frequency behavior remains unaltered.

A lower-loss, more compact alternative to the classical E-plane corrugated waveguide low-pass filter is proposed in this paper. The novel design is capable of achieving very steep slopes in the fundamental TEto-mode frequency response along with a drastic reduction in terms of insertion loss and size. The design method is based on step-shaped bandstop elements separated by very short waveguide sections. Moreover, the matching of the novel filter is achieved by very short input/output networks based on stubs of optimized heights. A simple method is proposed allowing the designer to obtain a compact low-pass filter fulfilling stringent specifications.