Programa del congreso

En este trabajo presentamos un método para diseñar bocinas cónicas compactas y ultra cortas corregidas por lentes dieléctricas para sistemas de comunicaciones inalámbricos. Mostraremos algunos prototipos de bocinas acortadas trabajando a 60 GHz con una razonable directividad y bajas pérdidas de retorno en una ancha banda de frecuencias.

This paper describes the design of a broadbandmicrostrip antenna, which is fed by a differential microstrip

line. The designed antenna is made of two stacked patches excited trough a dog-bone shaped aperture by a short-circuited differential microstrip line. The short-circuited differential line is symmetrically located with respect to the aperture so that its differential mode is naturally excited, while its common-mode

is intrinsically rejected. The antenna design is based on an equivalent circuit which includes a second-order Chebyshev filter composed of two capacitively coupled LC parallel resonators. In order to carry out the analysis and measurement of the antenna, a two-port feeding mechanism is introduced involving a 180º hybrid in such a way that the differential-mode excites the first port, while the common-mode excites the second port. A prototype of the differential microstrip antenna has been fabricated and measured, and good agreement has been found

between simulations and experiments. For a center frequency of 5.5 GHz, the prototype shows a fractional bandwidth close to 35 %, an average gain of 6.5 dBi, and crosspolar levels below -20 dB.

An inverted-L monopole radiating element is proposed for phased arrays at the mm-wave band. Its radiation pattern is half-isotropic and is well-suited for mobile communications. The ideal inverted-L monopole is analyzed by assuming a sinusoidal current and initial design values for the lengths of its segments are found to obtain half-isotropic radiation. Results are contrasted with simulations using a commercial software. The scanning capabilities and coverage of an array of such elements is shown. The beam coverage of the proposed array is very high, covering almost the whole space with a directivity of 15 dBi or more by using just two arrays of 16 elements.

Multiple-input multiple-output (MIMO) technology has emerged as a highly promising solution for wireless communication, offering an opportunity to overcome the limitations of traffic capacity in high-speed broadband wireless network access. By utilizing multiple antennas at both the transmitting and receiving Sub-6GHz ends, the MIMO system enhances the efficiency and performance of wireless communication systems [1]. This work presents a comparison of the performance of two families of M-CRotationally Symmetrical MIMO antenna design approaches one based on the Magneto Electric (ME) dipole antenna and a second one based on the Circular Cavity principle intended for their use into advanced MIMO applications like Orthogonal Angular Momentum (OAM) and high capacity channels. A comparison of the relevant performance parameters in terms of frequency bandwidth (both input impedance S_ii and inter-port isolation S_ij) and radiation pattern are presented for the two Sub-6GHz prototypes.

En este artículo presentamos un nuevo sistema

inalámbrico de transferencia de energía de alta eficiencia para

implantes biomédicos. El sistema consta de una antena

implantable de doble banda, una antena de parche desmontable

y un rectificador doblador de tensión. El transmisor tiene un

ancho de banda de impedancia inferior a -10 dB desde 1,461

hasta 1,48 GHz. Por su parte, el receptor de doble banda tiene

unos anchos de banda de impedancia del 23,4% y el 16,5% a 915

MHz (el ISM industrial, científico y médico) y 1,47 GHz,

respectivamente. Se ha observado una buena concordancia entre

los resultados medidos en el interior de carne picada de cerdo y

de salmón. Por último, se ha desarrollado un rectificador

ultrapequeño de 10 x 9 𝐦𝐦𝟐 para integrarlo en el dispositivo

implantable para la transferencia inalámbrica de energía.

This communication introduces an antenna with frequency-dependent scanning capabilities specifically tailored for the automotive radar application with a fixed center frequency of 24 GHz. The preliminary antenna design ensures high efficiency and maintains a low profile despite its metallic composition. With dimensions of 11.25 cm × 6.25 cm × 1.25 cm, this compact and low-profile antenna exhibits fast scanning characteristics within a narrow bandwidth. Over a mere 5% bandwidth, it achieves scanning angles of 45 degrees (−25 degrees to +20 degrees). Despite the absence of experimental validation, the simulated results exhibit a directivity close to 22 dBi with 90% radiation efficiency, necessitating further validation through experimentation.

This paper proposes a methodology to extract the equivalent circuit of a broadband microstrip antenna consisting of two stacked patches fed through a resonant rectangular aperture by an open-ended microstrip line. The equivalent circuit includes three LC parallel resonators, out of which two are inductively coupled and two are capacitively coupled. In order to extract the equivalent circuit of the antenna, its simulated input impedance is fitted as a rational function, and the coefficients of the polynomials involved in the rational function are obtained by the least squares method. Once the rational function is known, the equivalent circuit parameters are derived in terms of the polynomial coefficients and subsequently optimized. A broadband microstrip antenna with center frequency of 8.79 GHz and fractional bandwidth around 45\% has been designed and its equivalent circuit has been obtained. Good agreement has been found between the frequency response of the optimized equivalent circuit and that of the antenna.