Additive manufacturing (AM) is emerging as a key technology for the minimization and integration of microwave antenna systems. Among the several AM processes, selective laser melting (SLM) is rather convenient for waveguide components, since it allows for all-metal parts with a mechanical accuracy within 30–60 $\mu \text{m}$ and an equivalent surface electrical resistivity in the range of 10–20 $\mu \Omega \text {cm}$ . This paper reports on the assessment of the SLM applicability to the manufacturing of dual-polarization waveguide components operating in Ka-band, namely, a septum polarizer, a smooth-wall feed horn integrated with the septum polarizer, and an orthomode transducer (OMT). In order to achieve high electromagnetic performance in the Ka-band, the architectures have been optimized for the manufacturing process, above all in terms of orientation on the building platform and minimization of supporting structures. As a consequence, the corresponding prototypes exhibit measured performances in significant agreement with the predicted values. As an example, the return loss of all the components has been measured to be as high as 25 dB, while the measured isolation between the rectangular waveguide ports of the OMT is better than 47 dB.

Additive Manufacturing of Ka-Band Dual-Polarization Waveguide Components

A simple metasurface integrated with horn antenna exhibiting wide bandwidth, covering full Ku-band using 3D printing is presented. It consists of a 3D-printed horn and a 3D-printed phase transformation surface placed at the horn aperture. Considering the non-uniform wavefront of 3D printed horn, the proposed 3D-printed phase transformation surface is configured by unit cells, consisting of a cube in the centre which is supported by perpendicular cylindrical rods from its sides. Placement of proposed surface helps to improve the field over the horn aperture, resulting in lower phase variations. Both simulated and measured results show good radiation characteristics with lower side lobe levels in both E- and H-planes. Additionally, there is an overall increment in directivity with peak measured directivity up to 24.8 dBi and improvement in aperture efficiency of about 35% to 72% in the frequency range from 10–18 GHz. The total weight of the proposed antenna is about 345.37 g, which is significantly light weight. Moreover, it is a low cost and raid manufacturing solution using 3D printing technology.

https://www.mdpi.com/2079-9292/10/2/119/pdf

A Horn Antenna Covered with a 3D-Printed Metasurface for Gain Enhancement

Accuracy of complex internal channels produced by laser powder bed fusion process

i»?Modern 3D printing technologies, also known as additive manufacturing, have evolved rapidly in recent years and are currently used in a wide range of engineering applications. In particular, the use of the new manufacturing techniques is leading to the development of very promising 3D electromagnetic structures for millimeter-wave (mm-wave) devices [1]. Thanks to the very compet it ive performance of 3D printing in electromagnetic structures, both the industrial and research communities are paying special attention to this manufacturing technique, a novel fabrication process for polymer, metal, and ceramic materials. The technique is an attractive option for innovative and complex part fabrication, providing improvements in customization, part compactness, and rapid prototyping as well as reduced weight, cost, and mass production lead time.

Metal-Coated 3D-Printed Waveguide Devices for mm-Wave Applications [Application Notes]

Currently, artificial satellites are extensively used for scientific, military, and civil applications, particularly for telecommunications satellites.

Tunable Filtering Devices in Satellite Payloads: A Review of Recent Advanced Fabrication Technologies and Designs of Tunable Cavity Filters and Multiplexers Using Mechanical Actuation

A study on the passive microwave components made by polymer additive manufacturing (polymer jetting) is presented. Different types of components (waveguides, couplers, power dividers, filters and antennas) are designed to be made in a single part. Using a simple and cost-effective metallisation by applying silver paint, various prototypes with complex geometries have been manufactured to evaluate these proofs of concept and the robustness of the low-cost approach to make microwave components. Different measurements show that the obtained filters can provide an acceptable unloaded Q factor of 400–500 for the operating frequencies of 12–22 GHz. Waveguiding structures such as a mode converter, which is used as a broadband antenna, have also notably efficiently worked up to the Ka band (36 GHz). Due to a remarkable accuracy of nearly 80 µm, the obtained results of the proposed coupler, power divider and antennas are consistent with the full wave simulations, which prove that the currently available three-dimensional plastic printers can provide notably accurate prototypes to design original components.

Additive manufacturing of low cost and efficient proof of concepts for microwave passive components

Plastic and metal additive manufacturing technologies for hyperfrequency passive components up to Ka band

This paper presents a design of a micro-strip circularly polarized antenna intended for the Global Navigation Satellite Systems (GNSS). The presented device is composed of a micro-strip slotted patch antenna printed on a Rogers RO3006 substrate, a foam layer of 2 mm thick and a wideband commercial 3-dB SMT coupler. The combined fullwave antenna results with the measured S-Parameters of the coupler shows very good performances in terms of antenna matching and axial ratio on larger bandwidths.

Low-profile dual-band circularly polarized microstrip antenna for GNSS applications

This paper presents different metal deposition techniques used for the metallization of additively manufactured plastic components. Comparison between them are presented with a focus on their use with 3D printed Ka band bandpass filters. The results, in terms of conductivity, roughness and thickness, will be analyzed and measured up to 66 GHz by a resonant cavity method. The characterized metallization techniques will be applied on different 6th order bandpass filters working around 19 GHz.

Evaluation of metal coating techniques up to 66 GHz and their application to additively manufactured bandpass filters

This paper presents the design of a dual band filter for the integration of a RF receiver front-end in the L band. The synthesis from the imposed filtering specifications led us to choose the SIW technology that ensures a good trade-off between electrical performances and space requirements.

Johann Sence

Papers

Additive manufacturing of low cost and efficient proof of concepts for microwave passive components

Plastic and metal additive manufacturing technologies for hyperfrequency passive components up to Ka band

Low-profile dual-band circularly polarized microstrip antenna for GNSS applications

Evaluation of metal coating techniques up to 66 GHz and their application to additively manufactured bandpass filters

Compact dual-band filter in SIW technology for a L band receiver