A V-band single-layer low-loss slot-array antenna is presented in this paper. Radiating slots are backed by coaxial cavities which are fed through a Groove Gap Waveguide (GGW) E-plane corporate feed network. Cavity resonances are created by shortening nails with respect to the surrounding ones. This fact enables a compact single-layer architecture since coaxial cavities and feeding network can share the same bed of nails. A 16×16 array is designed, constructed and measured to demonstrate the viability of this concept for high-gain single-layer slot-array antennas. In addition, this solution can be extended to circular polarization by seamlessly adding a polarizer above the slots without changing the feeding network piece. Measurements show a relative bandwidth of 10% with input reflection coefficient better than -10 dB and a mean antenna efficiency above 70% within the operating frequency band (57-66 GHz).

The performance of an epsilon-near zero (ENZ) plano-concave lens is experimentally demonstrated and verified at the D-band of the millimeter-waves. The lens is comprised of an array of narrow metallic waveguides near cut-off frequency, which effectively behaves as an epsilon-near-zero medium at 144 GHz. A good matching with free space is achieved by exploiting the phenomenon of energy squeezing and a clear focus with a transmission enhancement of 15.9 dB is measured. The lens shows good radiation properties with a directivity of 17.6 dBi and low cross-polar components of -34 dB. All results are supported by numerical simulations.

The experimental validation of a Ku-band dual circularly polarized (CP) broadside-beam metasurface (MTS) antenna is presented. A radially modulated anisotropic single layer MTS has been synthesised employing sub-wavelength elliptical slotted metallic patches printed on top of a thin Arlon grounded substrate. In the structure, two decoupled phasematched transverse magnetic and transverse electric surface waves (SWs) are excited, which interact with the modulated surface leading to a CP broadside radiation. Two different orthomode transducers have been designed to excite the SWs with orthogonal polarization and equal amplitude. The first feeding system is composed of a metallic stepped septum inside an airfilled square waveguide. A conical section is included to match the output port of the square waveguide with the terminal, dielectric filled circular waveguide. The second feed is much more compact and efficient and it is composed of a circular waveguide completely filled by a dielectric. Depending on the input port excited on the feeds, two TE11 modes are excited with ±90° phase shift, which determine the right-hand or left-hand sense of the broadside beam generated by the MTS. Manufacturing details of the MTS and excitations are given and the measurements are compared with the simulation results. Finally, conclusions are drawn.

Today, telecommunication satellite horn antennas are required to be wideband mainly because of the additional bandwidth necessary to accommodate more transponders to increase the capacity of the new satellite services. In this aspect, horn antennas play a key role in the development of wider bandwidth services on board satellites because now-a-days, with recent advances in orthomode junctions and transducers, they are usually the bandwidth limiting component of a satellite antenna as often low crosspolar level is the toughest specification parameter. In this paper, the design guidelines for horn antennas that combine horizontal and vertical corrugations are explained, the method to prepare a preliminary profile for optimization is shown, and an example of a satellite feedhorn with severe requirements is presented.

In this work, a study of the performance of several antennas and components, manufactured using an accurate stereolithography three-dimensional printer and resin for maximum accuracy and detail, is carried out. Electroless plating of the components to cover the pieces with a thick copper layer to improve their mechanical resistance is undertaken. Several SatCom horn antennas and components are designed, manufactured, and tested. A detailed study of a spline horn antenna and a filter is covered. These results are compared to the metallic lathe manufactured versions. Conclusions are derived from these tests, which are useful to improve additive manufactured components in future versions.

A new concept of a really compact corrugated horn antenna for global coverage with very low sidelobe and cross-polar level and quite wide bandwidth is presented in this letter. This consists on the concatenation of a choke antenna together with a Gaussian profile horn antenna. A comparison of the performances of this horn design versus other author designs is included. A prototype was manufactured and measured and the results demonstrate excellent agreement with theoretical simulations.