Analysis and design of antennas and radiometers for radio astronomy applications in microwave, Mm-wave, and THz Bands

Abdalmalak Dawoud, Kerlos Atia

Publication:
Analysis and design of antennas and radiometers for radio astronomy applications in microwave, Mm-wave, and THz Bands

dc.contributor.advisor	García Muñoz, Luis Enrique
dc.contributor.author	Abdalmalak Dawoud, Kerlos Atia
dc.contributor.departamento	UC3M. Departamento de Teoría de la Señal y Comunicaciones	es
dc.date.accessioned	2022-06-15T09:59:53Z
dc.date.available	2022-06-15T09:59:53Z
dc.date.issued	2022-02
dc.date.submitted	2022-03-18
dc.description	Mención Internacional en el título de doctor
dc.description.abstract	We are living in interesting times for astronomy science, since the birth of the radio astronomy field in the 20th century by Karl Jansky, the availability of new and better radio astronomy receivers is in increasing demand to push the human understanding of the universe. In this thesis, various components (antennas, baluns, antenna-arrays, and radiometers) are proposed for radio astronomy receivers. The proposed designs are belonging to three receiver topologies (direct detection, down-conversion, and up-conversion) that operate at different frequency bands from MHz up to a few of THz. Also, to demonstrate that the same proposed design is capable of working efficiently at different operating frequencies, multiple adjusted designs are presented for several practical radio astronomy and space applications. Firstly, a receiver based on the direct detection of the Electromagnetic (EM) radiation through a radio telescope working on cryogenic cooling conditions. In this part, the focus is on designing conical log-spiral antennas and baluns (balanced to unbalanced transformers) to be used as feeds for VLBI Global Observing System (VGOS) ground-based radio telescopes. The feeds cover the Ultrawideband (UWB) from 2 GHz to 14 GHz with Circular Polarization (CP) radiation and stable radiation patterns. After integration of the feeds to the radio telescope, the whole system operates with high aperture efficiency and high System Equivalent Flux Density (SEFD) over the whole required wide range. The fabrication, assembly, and measurements for single-element and four-elements array are provided for achieving the requirements for single CP and dual CP operation. Also, in the same first part, the proposed single-element feed (antenna + balun) is readjusted for being used for CryoRad spaceborne Earth observations. This feed has a single CP over low-frequency UWB from 400MHz to 2 GHz with low weight and physical size compared to standard horn feeds. The second part of the thesis is dedicated to a THz source to be used as a local oscillator for heterodyne radio astronomy THz receivers in which the down-conversion of the THz radiation to a lower frequency occurs. The source is based on an array of self-complementary bow-tie antennas and photomixers that lies on a dielectric lens. The source can be scaled easily to cover different UWB ranges, three ranges are analyzed from 200 GHz to 2 THz, 100 GHz to 1 THz, and 50 GHz to 0.5 THz. Additionally, in this part, a complete study for the effects of metal losses on such THz planar antennas is performed which are not well-investigated in literature yet, the physical explanations behind such effects are also provided. Although these proposed THz sources themselves can work at room temperature, the receiver probably still needs the cooling for the other receiver components (such as the mixer) to work efficiently at such high frequencies. This is the motivation for the third part of this thesis which presents a different type of radio astronomy receiver that is completely able to work without cooling. The third receiver is based on the nonlinear up-converting of the microwave radiation into the optical domain using Whispering Gallery Mode (WGM) resonators which can work at room temperature efficiently. For such advantage and since this concept is naturally narrow-band, it can be a proper candidate for Cosmic Microwave Background (CMB) spectroscopy and space applications. The system design and its performance are analyzed for Ku band at 12 GHz with proposing a novel microwave coupling scheme for enhancing the up-conversion photonic efficiency which is the main limitation for such upconversion systems. Likewise, several high gain 3D-printed Dielectric Resonator Antenna (DRA)s are proposed in both isolated and array configurations to have a direct coupling of the microwave radiation to the proposed scheme. Another practical application for such receiver is presented for CubeSat missions at the mm-wave band (183 GHz) for climate change forecasting. It is clear here that removing the cryogenic cooling conditions decreases satellite weight and cost, which in turn significantly increases its lifetime. Also, it is worth noting that besides the radio astronomy applications, the proposed receivers (and/or their antenna/components) can be used for many other applications. For example, the UWB antennas in the first part can be used as wideband scalable probes for EM compatibility testing or other wireless systems that require single or dual CP such as radar and military applications. This is because the solutions provide constant beam characteristics with good CP polarization purity and stable performance over the operating UWB. In the same way, the proposed THz source in the second part can be used in several THz applications such as very high-speed wireless communications, highresolution imaging for medical and security purposes. This is because of its key benefits as decade bandwidth, compact size, low noise, low power demand, high tunability, and the ability to work at room temperature. For the up-conversion scheme proposed in the third part, due to its high photonic efficiency, low noise level which enables it to work at room temperature, and its scalability from a few GHz up to several THz, it is suitable for low-cost and high sensitivity applications. Specifically, the ones that need to get rid of the hard cryogenic cooling conditions, or at least, relax them and allow the system to work efficiently at higher temperatures. For instance, portable mm-wave and THz systems for quality control, security, and biochemistry. Finally, in this part, the proposed DRA elements and arrays, due to their low cost, high gain, and low losses, can be used for sensing applications and 5G base station antennas.	en
dc.description.degree	Programa de Doctorado en Multimedia y Comunicaciones por la Universidad Carlos III de Madrid y la Universidad Rey Juan Carlos	es
dc.description.responsability	Presidente: Raed Shubair.- Secretario: Adrián Amor Martín.- Vocal: José Manuel Fernández González	es
dc.identifier.uri	https://hdl.handle.net/10016/35126
dc.language.iso	eng	en
dc.relation.haspart	https://doi.org/10.1109/TAP.2019.2949700
dc.relation.haspart	https://doi.org/10.1109/EuCAP.2016.7481889
dc.relation.haspart	https://doi.org/10.1109/APUSNCURSINRSM.2017.8072812
dc.relation.haspart	https://doi.org/10.1109/GSMM.2016.7500321
dc.relation.haspart	https://doi.org/10.23919/EuCAP48036.2020.9135409
dc.relation.ispartof	https://doi.org/10.1109/TAP.2019.2949700
dc.relation.ispartof	https://doi.org/10.1109/ACCESS.2020.3007576
dc.relation.ispartof	https://doi.org/10.1007/s10762-016-0310-9
dc.relation.ispartof	https://doi.org/10.1038/s41598-020-65987-x
dc.relation.ispartof	https://doi.org/10.1109/LAWP.2019.2939734
dc.relation.ispartof	https://doi.org/10.1364/OPTICA.5.001210
dc.relation.ispartof	https://doi.org/10.1007/s10762-019-00612-1
dc.relation.ispartof	https://doi.org/10.1364/OE.24.026503
dc.relation.ispartof	https://doi.org/10.23919/EuCAP.2017.7928543
dc.relation.ispartof	https://doi.org/10.1109/IWAT.2017.7915341
dc.relation.ispartof	https://doi.org/10.23919/EuMC.2018.8541628
dc.relation.ispartof	https://doi.org/10.23919/EuCAP48036.2020.9135962
dc.relation.ispartof	https://doi.org/10.23919/EuCAP48036.2020.9135409
dc.relation.ispartof	https://doi.org/10.1117/12.2555654
dc.relation.ispartof	https://doi.org/10.1109/IRMMW-THz.2019.8874282
dc.relation.ispartof	https://www.nrao.edu/meetings/isstt/papers/2019/2019229232.pdf
dc.relation.ispartof	https://www.dpg-verhandlungen.de/year/2019/conference/regensburg/part/kfm/session/4/contribution/5
dc.relation.ispartof	https://doi.org/10.1109/APWC.2019.8870395
dc.relation.ispartof	https://doi.org/10.1109/APUSNCURSINRSM.2017.8072681
dc.relation.ispartof	https://doi.org/10.1109/NEMO.2017.7964218
dc.rights	Atribución-NoComercial-SinDerivadas 3.0 España	*
dc.rights.accessRights	open access	en
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/es/	*
dc.subject.eciencia	Astronomía	es
dc.subject.eciencia	Telecomunicaciones	es
dc.subject.other	Radio astronomy	en
dc.subject.other	Antennas	en
dc.subject.other	Radiometers	en
dc.title	Analysis and design of antennas and radiometers for radio astronomy applications in microwave, Mm-wave, and THz Bands	en
dc.type	doctoral thesis	*
dspace.entity.type	Publication