Project for the design and construction of a LEO (Low Earth Orbit) Satellite Earth Station

The main objective of this thesis is to develop a fully functional and modular satellite ground station located in the ESEIAAT in order to track, monitor and do the housekeeping of current and future low earth orbit satellites operating in the UHF band.This main purpose of this project is to prepare a fully-operational Satellite Ground Station. Moreover, it also pursues to give a remote control capability to it. This has been done by designing and building two major blocks: the Hardware system and the Software system. In order to actually test the solution, the thesis participated in a real space mission by the hand of OpenCosmos Ltd. It was known that qb01, which is OpenCosmos first cubesat, will be launched during the development of this thesis. That is why, the ground station selected qb01 as its design point, while constantly trying to generate a solution as general as possible to any satellite. Therefore, a UHF band, half-duplex SDR based system for LEO satellites was designed. Finally, the system was verified by being used in real operations by the satellite operators

Project for the design and construction of a LEO (Low Earth Orbit) Satellite Earth Station

The main objective of this thesis is to develop a fully functional and modular satellite ground station located in the ESEIAAT in order to track, monitor and do the housekeeping of current and future low earth orbit satellites operating in the UHF band.This main purpose of this project is to prepare a fully-operational Satellite Ground Station. Moreover, it also pursues to give a remote control capability to it. This has been done by designing and building two major blocks: the Hardware system and the Software system. In order to actually test the solution, the thesis participated in a real space mission by the hand of OpenCosmos Ltd. It was known that qb01, which is OpenCosmos first cubesat, will be launched during the development of this thesis. That is why, the ground station selected qb01 as its design point, while constantly trying to generate a solution as general as possible to any satellite. Therefore, a UHF band, half-duplex SDR based system for LEO satellites was designed. Finally, the system was verified by being used in real operations by the satellite operators

Development of a Cryocooler-based Remote Cooling System at Low Temperature

Remote cooling systems are a promising technology that could close the existing gap in cooling power between the powerful cryoplants and the compact, low-power, cryocoolers. Such systems could be accomplished by adding a carefully designed convection loop to a cryocooler. This upgrade has several advantages, notably decoupling mechanically and spacially the cooling interface from the cryocooler, enabling applications that could otherwise be harmful for the latter or that are sensitive to vibrations, as well as increasing the total cooling power capabilities. A critical component of the remote cooling systems under development is a counter-flow heat exchanger (CFHEX). Very high CFHEX effectiveness values (above 95%) are required to achieve high system cooling powers. With that in mind, the focus of this thesis is twofold. On the one hand, an analysis of different remote cooling system architectures was performed to determine their best fitness for a range of applications. The prototype systems were found to reach ~3.5 W of cooling power with only 2 W available at the cryocooler alone, both at 4.5 K. On the other hand, several measurement campaigns and its data post-processing were carried out on the novel CFHEX design. Effectiveness values of up to 98% were reached, exceeding the initial 95% goal

Semi-Dry Cooling Solutions for Future Superconducting Accelerator Structures

Cryogenic dry cooling solutions for Superconducting RF cavities allow for synergies with modern cavity production methods based on vacuum coating and A15 SC layer deposition methods. A proof-of-concept cryogenic performance test stand will study relevant parameters of low-temperature cooling loops with respect to the RF performance of a 1.3 GHz prototype cavity. The paper describes cooling options concerning helium forced flow heat transfer at the capillary surface plus the conduction pathway and the consequent temperature distribution in the cavity itself. Such novel and drastically reduced helium content cooling schemes can be applied to a wide variety of SC cavity or magnet assemblies. The results of the numerical evaluation of heat transfer and pressure drop relations for two-phase and single-phase supercritical flow are cited. These data form the basis for future experimental validation campaigns in the temperature range of 4.2 K to 25 K and helium pressures of up to 2.2 MPa. Special attention is paid to possible new introduced effects of mechanical vibrations or temperature gradients along the cooling capillary when compared to a stagnant He bath cooling