Diseño de agrupaciones de antenas alimentadas con redes corporativas en tecnología de guía de onda

Tradicionalmente en el grupo de investigación RFCAS se han diseñado redes de alimentación de diversa índole, como son por ejemplo redes tipo serie o paralelo en tecnología microstrip o SIW. Sin embargo, para el caso de redes en tecnología de guía de onda la distribución tipo serie ha sido la más utilizada debido al ahorro de espacio que conlleva frente a la de tipo paralelo. De hecho, agrupaciones en paralelo distribuidas sobre el plano E ni siquiera han sido estudiadas. En el presente documento se ha procedido a analizar el comportamiento de distintas agrupaciones de antenas alimentadas por redes corporativas en tecnología de guía de onda. Se ha partido de la hipótesis de que el elemento unitario de las agrupaciones a estudiar se iba a comportar de manera adecuada cuando fuera replicado a lo largo de las diferentes estructuras que se han propuesto. De este modo se han podido extraer las conclusiones pertinentes sobre el comportamiento de las distintas redes diseñadas, independientemente del tipo de array que ha sido alimentado con ellas. Como elemento radiante se ha tomado uno perteneciente al grupo de investigación RFCAS ya diseñado y medido, el cual consiste en un parche circular microstrip apilado sobre una ranura rectangular microstrip para polarización lineal, que es alimentado a través de una guía de onda rectangular estándar WR-51. El diseño ha sido optimizado para la porción superior de la banda Ku del espectro radioeléctrico, de 16 a 18 GHz. Las estructuras en guía que se han propuesto han sido dos arrays lineales de 4 elementos, uno de ellos en plano H y el otro en plano E. Por lo tanto, gran parte del trabajo que se ha realizado ha tratado sobre el modelado de los distintos elementos de que se componen las redes de alimentación corporativas que alimentan dichos arrays, tales como uniones en T, en Y o codos en ambos planos. Todos los diseños planteados han sido construidos y medidos como paso posterior a la etapa de diseño. Finalmente, se ha diseñado una transición de guía de onda a conector coaxial para el caso del plano H, debido a la imposibilidad de cargar todos los puertos de la red a su impedancia característica para medirla en transmisión. Dicha transición ha sido replicada por 4 en una única pieza, lo que ha permitido caracterizar el array de elementos radiantes y la red de alimentación corporativa por separado. Con todo esto se ha realizado un estudio muy completo de los elementos de que se compone la antena plano H, y se ha verificado si el parámetro de adaptación de la citada antena se corresponde con el de la red de alimentación y el array de parches sobre ranuras medidos por separado.Several kind of feeding networks had been conventionally designed in RFCAS research group, such as serial or parallel network based on microstrip or substrate integrated waveguide (SIW) technology. Nevertheless, waveguide technology had been mainly used in serial feeding structures design owing to their space-saving properties in comparison to parallel example. As a matter of fact, E-plane parallel arrays had been never studied at RFCAS. In the present document different array antenna configurations fed by corporate waveguide feeding networks are analyzed. As a starting point, it is assumed that the single element of all array antennas would behave appropriately when it is replicated along the different proposed structures. This way, conclusions about all designed networks had been drawn regardless of which array antenna type was being fed. The selected radiating element belongs to RFCAS and it is already designed and measured. It consists of a circular microstrip patch stacked to a microstrip slot fed by a standard WR-51 waveguide for linear polarization. Designed antenna is optimized for upper Ku band part, from 16 to 18 GHz. Proposed waveguide structures are two 4-element linear arrays, one at H-plane and E-plane respectively. Therefore, outlining both E-plane and H-plane elements such as Tjunctions, Y-junctions and bends became the major part of the developed work. All the presented designs have been manufactured and measured. Finally, a coaxial to waveguide transition has been designed for H-plane antenna due to output load matching is not physically possible. This transition is repeated 4 times in a single piece, so both array of radiating elements and corporate waveguide feeding network are accessible to be measured separately. All this leads to an exhaustive characterization of the elements which form part of the complete H-plane array antenna. Adaptation coefficient is measured from complete antenna input port. It is also estimated by joining both array of radiating elements and corporate waveguide feeding network Sparameters so this measures can be validated

Evaluation of a Planar Reconfigurable Phased Array Antenna Driven by a Multi-Channel Beamforming Module at Ka Band

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksIn this paper, a planar active phased array antenna demonstration with linear polarization (LP) at Ka Band (28-30 GHz) is presented. The proof of concept is carried out to evaluate the possible problems that may arise, to analyze possible calibration stages and to assess the viability of the integration of an active system with a Multi-Channel Beamforming Module (MCBM). To fulfill this task an 8times 8-element planar array arranged in column subarrays of 1times 8 elements for 1D beam steering is proposed. The single element consists of a printed circular patch connected to a microstrip feeding line through metallic vias in a multilayered structure. Both the amplitude and phase distributions are performed by a commercial integrated circuit (IC) designed for transmission purposes, from the common port to each of the 8 output ports. Thus, an evaluation of the IC performance is also included within this work. Despite the inherent amplitude and phase feeding errors of the IC, the beam-steering accuracy of the system is reasonable. A nice correspondence between the simulated and measured 8times 8-element array beam steering directions is obtained, with errors below 1° in the steering of the beamThis work was supported in part by the Spanish Government, Ministry of Economy, National Program of Research, Development and Innovation through the Project FUTURE RADIO ’’Radio systems and technologies for high capacity terrestrial and satellite communications in an hyperconnected world’’ under Grant TEC2017-85529-C3-1-R, and in part by the Project JETSTREAM ’’Desarrollo de una antena banda KA embarcada para la prestación de servicios de acceso a Internet por satélite en aviación comercial’’ in collaboration with TELNET Redes Inteligentes S.A. under Grant RTC-2015-3495-

Mechanically reconfigurable linear phased array antenna based on single-block waveguide reflective phase shifters with tuning screws

This work presents the design and prototyping of a reconfigurable phased array in Ku band (16 to 18 GHz) implemented in waveguide technology. The design is based on the use of a novel seamless waveguide module integrating four reconfigurable phase shifters to adjust the relative phase shift between the unitary elements of a linear array, which are illuminated uniformly by a corporate waveguide feeding network. The phase shifters are implemented by a 90º hybrid coupler in waveguide technology where two of its ports are loaded with a tunable reactive load, implemented in this proof of concept with a tuning screw. The four phase shifters have been manufactured in a single part using direct metal laser sintering, avoiding the losses related to bad electric contacts and misalignments associated to multipart devices. This also simplifies the assembly of the full phased array, leading to a modular approach with three parts whose design can be addressed separately. The experimental results for the complete array antenna show great performance and demonstrate that the main-lobe of the radiation pattern can be effectively scanned continuously between the angles - 25º and 25º, with a high efficiency in the whole design band thanks to the proposed waveguide implementationThis work was supported by the Spanish Government, Agencia Estatal de Investigación, Fondo Europeo de Desarrollo Regional: AEI/FEDER, UE, under Grant TEC2016-76070-C3-1-

Multi-probe measurement system based on single-cut transformation for fast testing of linear arrays

This paper introduces a near-field measurement system concept for the fast testing of linear arrays suited for mass production scenarios where a high number of nominally identical antennas needs to be measured. The proposed system can compute the radiation pattern, directivity and gain on the array plane, as well as the array complex feeding coefficients in a matter of seconds. The concept is based on a multi-probe antenna array arranged in a line which measures the near field of the antenna under test in its array plane. This linear measurement is postprocessed with state-of-the-art single-cut transformation techniques. To compensate the lack of full 3D information, a previous complete characterization of a “Gold Antenna” is performed. This antenna is nominally identical to the many ones that will be measured with the proposed system. Therefore, the data extracted from this full characterization can be used to complement the postprocessing steps of the single-cut measurements. An X-band 16-probe demonstrator of the proposed system is implemented and introduced in this paper, explaining all the details of its architecture and operation steps. Finally, some measurement results are given to compare the developed demonstrator with traditional anechoic measurements, and show the potential capabilities of the proposed concept to perform fast and reliable measurements.This work was funded by Indra Sistemas S.A. and by the Spanish Government, Ministry of Economy, National Program of Research, Development and Innovation through the project FUTURERADIO “Radio systems and technologies for high capacity terrestrial and satellite communications in an hyperconnected world” (project number TEC2017-85529-C3-1-R)

Multi-Probe Measurement System Based on Single-Cut Transformation for Fast Testing of Linear Arrays

This paper introduces a near-field measurement system concept for the fast testing of linear arrays suited for mass production scenarios where a high number of nominally identical antennas needs to be measured. The proposed system can compute the radiation pattern, directivity and gain on the array plane, as well as the array complex feeding coefficients in a matter of seconds. The concept is based on a multi-probe antenna array arranged in a line which measures the near field of the antenna under test in its array plane. This linear measurement is postprocessed with state-of-the-art single-cut transformation techniques. To compensate the lack of full 3D information, a previous complete characterization of a “Gold Antenna” is performed. This antenna is nominally identical to the many ones that will be measured with the proposed system. Therefore, the data extracted from this full characterization can be used to complement the postprocessing steps of the single-cut measurements. An X-band 16-probe demonstrator of the proposed system is implemented and introduced in this paper, explaining all the details of its architecture and operation steps. Finally, some measurement results are given to compare the developed demonstrator with traditional anechoic measurements, and show the potential capabilities of the proposed concept to perform fast and reliable measurements

Multi-Probe Measurement System Based on Single-Cut Transformation for Fast Testing of Linear Arrays

This paper introduces a near-field measurement system concept for the fast testing of linear arrays suited for mass production scenarios where a high number of nominally identical antennas needs to be measured. The proposed system can compute the radiation pattern, directivity and gain on the array plane, as well as the array complex feeding coefficients in a matter of seconds. The concept is based on a multi-probe antenna array arranged in a line which measures the near field of the antenna under test in its array plane. This linear measurement is postprocessed with state-of-the-art single-cut transformation techniques. To compensate the lack of full 3D information, a previous complete characterization of a “Gold Antenna” is performed. This antenna is nominally identical to the many ones that will be measured with the proposed system. Therefore, the data extracted from this full characterization can be used to complement the postprocessing steps of the single-cut measurements. An X-band 16-probe demonstrator of the proposed system is implemented and introduced in this paper, explaining all the details of its architecture and operation steps. Finally, some measurement results are given to compare the developed demonstrator with traditional anechoic measurements, and show the potential capabilities of the proposed concept to perform fast and reliable measurements