P1 – Satellite Front-End for Non-Terrestrial 6G
The aim of this PhD project is to develop innovative phased arrays architectures for 6G satellites, that must radiate multiple beams in Rx/Tx with high gain over a wide angular sector in reconfigurable frequency bands, while complying with severe power consumption and accommodation constraints. New concepts based on deployable phased arrays must be explored with integrated radiating elements with wide angle scanning capability over multiple bands, with hybrid beamforming (RF, digital, photonic), distributed filtering and amplification, resulting in a low profile, integrated and deployable antenna. The expected outcome of this project is an assessment of several antenna architectures based on different approaches. The key building blocks must be designed and prototyped.
P2 – Integrated Photonic-RF front-end
The objective of this PhD project is to explore and develop integrated photonic RF front-end solutions based on the latest integrated photonics platforms (incl. InP, Silicon, Ln/Si, IMOS) to squeeze the SWAP of these interfaces while maintaining the required level of RF performance. The PhD student is expected to study suitable modulator technologies for both phase and intensity modulation (with MZM or electro-absorption modulators) and to design an integrated photonic front-end for transmission of Ka-band RF signals with and without frequency conversion. The compatibility and potential for co-integration with optical beamforming shall be analyzed. The expected outcome includes a SWAP analysis for integrated photonic-RF front-ends considering the latest integrated photonics platforms and different modulator technologies as well as the design and prototype of a novel power-efficient integrated photonic-RF front-end.
P3 – Integrated HPA-antenna co-design at Ka-band
This project aims at the design of a highly efficient and compact front-end radiating module for Ka-band satellite downlink flat panel antennas. The thickness, the mass and the cost of the front-end radiating modules shall be significantly reduced while keeping a high level of performance. This shall be achieved through the co-design between the radiating elements and the power amplifiers. Filtering and circular polarization will also be addressed.
P4 – Integrated HPA-antenna co-design for L-/S-band
The research will address the integrated design of linearized and efficiency-enhanced dual-band PA architectures with multi-functional on-antenna combining functionality for circularly dual-polarized active antenna array operation at L-/S-bands. Multi-domain nonlinear analysis techniques, involving signals, circuits- and EM characteristics will be developed for prediction of the performance of array unit cells in large array satellite application scenarios. The expected outcome of this project is a proof-of-concept demonstration of an energy efficient unit cell for L-/S-bands active antenna transceiver. Moreover, a detailed prediction of performance in terms of linearity, efficiency and radiated field pattern when used in 6G satellite link applications shall be a main outcome of the study.
P5 – On-antenna multi-functional power combining technologies for mm-wave frequencies
The PhD student is expected to develop a new method for on-antenna multi-functional power combining at mm-wave frequencies that can enable linearly dual-polarized, full duplex active antenna systems. The key enabler as presently considered is distributed active feeding of the radiating antenna element that provides tailored power combining and impedance matching with mm-wave power amplifiers. A proof-of-concept demonstration in simulations, joint electromagnetic-circuit simulation results, experimental prototype, and experimental validation results for the developed method for on-antenna multi-functional power combining for dual-polarized, full duplex active antenna systems are expected outcomes of this PhD project.
P6 – Integrated Filtering Antenna Array Solutions for Satellite Communications
This project is focused on the development of integrated filtering antenna array solutions for beyond-5G, or 6G, satellite communications. Emphasis is placed on the design of the integrated solutions with various synthesis methods to optimize the frequency selectivity, quality factor, out-of-band suppression, stability of the in-band gain, and antenna efficiency.
P7 – Generic Phased Array Feed for G/T optimization and RFI resilience
This project aims to investigate the feasibility of applying the phased array feed technology in non-terrestrial communication networks. Towards this end, this work aims to demonstrate that such technology can optimize ground station antenna performance for maximum gain-to-noise ratio towards a single, or multiple, satellite(s) within a confined field-of-view, while at the same time spatially nulling local interfering radio frequency sources. To deploy a phased array receiver on various reflector systems, a generic phased array demonstrator is to be designed that would enable multi-beam coverage from different reflector antennas.
P8 – Advanced Manufacturing for high frequency feed systems
Additive manufacturing (AM) of high-frequency feed-systems is an emerging technological solution in the NTN communication domain since it can lead to a higher level of antenna-subsystems miniaturization and integration. AM of feed systems exhibit some criticalities in terms of dimensional accuracy and repeatability, surface roughness, and electrical conductivity. These criticalities will be addressed in this project by both improving the manufacturing processes and designing smart antenna-subsystem layouts that are customized to AM. Other advanced machining technologies, including e.g. silicon and metal micromachining, will be considered as viable solutions, also addressing future millimeter-wave and subTHz satellite payloads.
P9 – Dual-band mm-wave phased array for LEO SatCom broadband user terminal
This PhD research aims at developing a smart dual-band mm-wave array antenna for Low Earth Orbit SATCOM broadband user terminals that can enable both the Rx and Tx bands in the same antenna aperture, while supporting a circular polarization operation over a wide beam steering range with high efficiency. The project shall cover the electromagnetic design, numerical simulation results, analysis of suitable manufacturing technologies, mechanical design, and experimental verification results of a prototype.
P10 – 3D radiating elements integrated with RF/digital BFN on board
Nowadays, several 3D array elements are being developed in the millimetre wave bands. Hybrid solutions such as dual-polarized Vivaldi radiating elements will be developed to assure a high radiation efficiency for satellite communication. In this way, sparse array solutions could be investigated to trade-off array complexity and scan angle capabilities (field-of-view). Both analog and digital beam forming strategies will be considered to achieve an integrated array building block with excellent RF, power, EMC, thermal and mechanical characteristics for future space applications.
P11 – Maximally sparse 3D antenna arrays
Recent research on multi-exponential analysis has demonstrated perfect signal recovery from sparsely sampled signals. This project aims to extend the application of this analysis to the spatial domain by applying the theory of multi-exponential analysis to the synthesis of a maximally sparse conformal antenna array enabling near-hemispherical field-of-view coverage. The theoretical framework developed through this research will be applied to the design of a demonstrator Low-Earth Orbit ground station 3D phased array antenna operating in K- (downlink) and Ka-band (uplink), with improved circular polarization purity and scan performance at near-horizon elevation angles.
P12 – Beam prediction for fast-moving LEO
This project aims to enhance spectral efficiency in non-terrestrial networks (NTN) using low earth orbit (LEO) satellites, with a specific focus on both downlink and uplink beamforming to mitigate channel path loss. Our goal is to develop innovative algorithms that minimize initial access training time while maximizing accuracy, aligning with the challenges posed by the sixth-generation (6G) standard. We will also explore information-theoretic limits on training duration in LEO satellite links and investigate beam-tracking strategies for fast-moving LEO satellites, leveraging their predictable orbits.
P13 – Synchronisation under harsh Doppler
In future communication networks, satellite-based transmission will be of great relevance. In face of the associated high speeds and increased frequency bands, the channel varies rapidly and Doppler shifts will be significantly larger than in terrestrial-based networks. In this project, we aim at developing standalone techniques for synchronisation under such harsh conditions. Initially, we study pilot-based solutions. We also develop data-driven solutions for more rapid updates.
P14 – Dynamic high-pathloss doppler-enabled OtA emulator
System test solutions that include the antenna interface do not readily exist. Therefore, this project aims at developing a measurement solution to realistically emulate highly dynamic scenarios for communications. The outcome shall be a new concept, demonstrated in an anechoic chamber, which allows emulation characteristics (with a focus on doppler) currently implemented in costly and not-frequency-scalable electronics.
P15 – Inter-satellite communication and synchronisation
To avoid discontinuity in the service of UEs, there is a need for a seamless handover, whenever the UE moves from one LEO-satellite beam to another. Cooperation between NTN nodes becomes then essential, and it can be attained only by a reliable and efficient inter-satellite communication. Inter-satellite communications present a series of challenges that need to be addressed in this project, i.e., flexibility, autonomy and self-organization due to time-varying topology, physical-layer design in the mm-wave, THz and optical bands and synchronization to achieve seamless handover between satellites. Machine-learning techniques will play an important role to address such challenges.
