Programa del congreso

In this paper, a flat lens antenna using Gap Waveguide (GW) technology working in the millimeter waves band is designed. The metamaterial lens is fed using a Groove Gap Waveguide (GGW) horn antenna in order to achieve a plane wavefront at broadside. Both devices, metalens and GGW antenna achieve excellent radiation results when combined together. Due to the fully metallic composition, the structure presents more robustness, low loss, and adaptability to a flat surface, apt for millimeter wave application.

In this work, the design of a band-pass filter, based on a periodic structure that uses modified sections of a single-ridge waveguide (SRW) as the unit cell to produce the electromagnetic band-gap (EBG) at the desired frequency, is successfully addressed. The effect of the dimensions of the SRW height profiles in the different characteristics of the filter (lower cut-off frequency, and center frequency and bandwidth of the rejection-band) is analysed through the dispersion diagram of the infinitely periodic structure with different unit cells. The proposed topology and design process is used to implement a 54% fractional bandwidth band-pass filter centered at 5.4 GHz using low-cost 3D additive manufacturing techniques, which allow fast prototyping and the fabrication of complex geometries. Experimental measurements are in good agreement with the expected simulated response of the designed band-pass filter, showing good matching in the pass-band, and a deep rejection band.

In this article, three dual circularly-polarized K-band horn antennas are designed and experimentally validated. All designs are based on a common topology: a square waveguide input, a bowtie-shaped polarizer, and a flare section. Either left or right-handed radiation can be achieved by exciting one of the degenerate modes in the square waveguide. The bowtie polarizer outstands as a simple, easy-to-manufacture way of obtaining circular polarization. The three designs differ just in the flare section: a circular aperture, a square aperture and a bowtie-shaped aperture have been considered. The advantages of each aperture type will be discussed. The prototypes have been manufactured by Direct Metal Laser Sintering, allowing a single-block assembly. Over 20% bandwidth with axial ratio under 3 dB and gain around 19 dBi has been experimentally obtained in the three designs.

This paper presents the design, optimization and simulation of a novel 12x12 W-Band waveguide slotted array antenna based on stacked glide-symmetric metal sheets fed by a groove gap waveguide (GGW). This paper also proposes a new unit cell. The suggested unit cell has serpentine-shaped holes in a glide-symmetric configuration with the goal of minimizing the separation between parallel waveguides. To demonstrate the viability of the proposed unit cell, a 12x12 W-Band waveguide slotted array antenna at 92 GHz was designed and simulated. The results show that the proposed slot array antenna has a reflection coefficient below −10 dB within 91.3 GHz to 93 GHz, and the peak directivity and gain are about 29.7 dBi and 28.8 dB, respectively, at 92 GHz.

This paper shows in detail the 3D printing and electroplating process for a WR-28 rectangular waveguide. The characteristics of the printing process that must be taken into account to obtain the best possible print and to avoid problems that may arise are analyzed. Several studies are also carried out on the copper plating process using the electroplating method, changing the current applied to the piece, the amount of plating time and adding a copper deposition retardant additive that helps to reduce the roughness of the surfaces. In addition, possible errors that can lead to faulty electroplating are discussed.