PhD Position Full Wave Inversion Using Data-Driven Operators for GNSS-R Data

Change: exploiting reflections from global navigation satellite system through full waveform inversion.

Impact: better products from satellite data.

Job description

The "GNSS-R Satellite Earth Observation (GLITTER)" project harnesses the power of GNSS-R (Global Navigation Satellite System-Reflectometry) for advanced Earth observation. This technique uses the reflections of GNSS signals off various surfaces—land, sea, and ice—to monitor environmental conditions. Our ambitious goal is to pioneer a new generation of experts capable of making significant advancements in this field through doctoral-level education and research. At the heart of GLITTER is the development of a synchronized constellation of Cubesats, offering a cost-effective yet powerful approach to Earth observation. This innovative system allows for enhanced resolution and data accuracy through advanced beamforming techniques. Essential to our methodology are ground-truth data and calibration methods derived from near-field radar technology, which will enable comprehensive research across all facets of GNSS-R technology. This includes the launching and adjustment of Cubesat formations, RF synchronization, interferometry between moving platforms, and calibration of RF front-ends, alongside ground testing with drones and cubesat systems, on-board processing, data transfer, and analysis. The project's scope extends beyond GNSS-R technology to potentially revolutionize fields that use interferometry, like radio astronomy and phased-array-based communications. Moreover, GLITTER aims to support various industry sectors, including precision agriculture, forestry, and land and sea management.

The GLITTER initiative positions Doctoral Candidate 06 to revolutionise the ability to retrieve information from the reflecting surface using Global Navigation Satellite Systems-based Reflectometry (GNSS-R).

The first step is to compute electromagnetic wave field propagation operators from GNSS-R data recorded at multiple receivers. Formation flight nano-satellites will provide the opportunity to generate a dense virtual antenna array near the ground surface, improving the possible resolution of surface and subsurface soil moisture maps. Then, 3D full-wave inversion using redatumed GNSS-R data will be investigated to make surface and subsurface soil moisture maps. Survey design for nano-satellite formation flight and ground-based receiving antennas will allow for the ability to compute data-driven wave propagation operators . Including Bayesian methods in the inverse problem will improve the ability to select the most likely subsurface models (in joint effort with PolyChord) and the results will be calibrated with drone-borne GPR results (in joint effort with UCLouvain). The expected outcome is a validated algorithm and computer code that combines data-driven propagation operators and full-wave inversion to make surface and subsurface moisture maps.

The objectives of this PhD project are to develop and validate 1) algorithms to retrieve virtual reflection responses from multi-source-receiver GNSS-R data, and 2) full-wave inversion by joint model- and data-driven methods.

Requirements

The successful candidate should hold an MSc degree in Physics, Geophysics, Electrical Engineering, Mathematics, or related field, should have knowledge of and proven ability to work with wave propagation and representation theorems, have strong numerical and programming skills for forward and inverse problems.

The candidate should be a good communicator, have a broad interest and learn quickly. The candidate should possess excellent writing and verbal communication skills in English.

Doing a PhD at TU Delft requires English proficiency at a certain level to ensure that the candidate is able to communicate and interact well, participate in English-taught Doctoral Education courses, and write scientific articles and a final thesis.

This PhD position is part of the EU Doctoral network GLITTER.

Conditions of employment

Doctoral candidates will be offered a 4-year period of employment in principle, but in the form of 2 employment contracts. An initial 1,5 year contract with an official go/no go progress assessment within 15 months. Followed by an additional contract for the remaining 2,5 years assuming everything goes well and performance requirements are met.

Salary and benefits are in accordance with the Collective Labour Agreement for Dutch Universities, increasing from € 2.872 per month in the first year to € 3.670 in the fourth year. As a PhD candidate you will be enrolled in the TU Delft Graduate School. The TU Delft Graduate School provides an inspiring research environment with an excellent team of supervisors, academic staff and a mentor. The Doctoral Education Programme is aimed at developing your transferable, discipline-related and research skills.

The TU Delft offers a customisable compensation package, discounts on health insurance, and a monthly work costs contribution. Flexible work schedules can be arranged.

For international applicants, TU Delft has the Coming to Delft Service. This service provides information for new international employees to help you prepare the relocation and to settle in the Netherlands. The Coming to Delft Service offers a Dual Career Programme for partners and they organise events to expand your (social) network.

Each host organisation will appoint the successful applicant under an employment contract with a very competitive salary. The fellow is expected to join their host organizations starting from September 1st, 2024 (estimated time). Additional funding for participation to courses, workshops, conferences, etc. is ensured.

All positions include a doctoral track and the successful applicant will be registered for the PhD program at the host institution. If the doctoral track requires a longer duration than 48 months, the details and financial implications will be provided by the host institution.

TU Delft conditions apply. In addition, the MSCA WORKING CONDITIONS apply:

Each DC will receive help in establishing and implementing a Personal Career Development Plan (PCDP). PCDP will be agreed and signed by supervisor and DC.

DC contract will reflect GA requirements, confirmed via Mobility Declaration (to be submitted on the F&T Portal within 20 days after the signature of the contract).

TU Delft (Delft University of Technology)

Delft University of Technology is built on strong foundations. As creators of the world-famous Dutch waterworks and pioneers in biotech, TU Delft is a top international university combining science, engineering and design. It delivers world class results in education, research and innovation to address challenges in the areas of energy, climate, mobility, health and digital society. For generations, our engineers have proven to be entrepreneurial problem-solvers, both in business and in a social context.

At TU Delft we embrace diversity as one of our core values and we actively engage to be a university where you feel at home and can flourish. We value different perspectives and qualities. We believe this makes our work more innovative, the TU Delft community more vibrant and the world more just. Together, we imagine, invent and create solutions using technology to have a positive impact on a global scale. That is why we invite you to apply. Your application will receive fair consideration.

Challenge. Change. Impact!

Faculty Civil Engineering & Geosciences

The Faculty of Civil Engineering & Geosciences (CEG) is committed to outstanding international research and education in the field of civil engineering, applied earth sciences, traffic and transport, water technology, and delta technology. Our research feeds into our educational programmes and covers societal challenges such as climate change, energy transition, resource availability, urbanisation and clean water. Our research projects are conducted in close cooperation with a wide range of research institutions. CEG is convinced of the importance of open science and supports its scientists in integrating open science in their research practice. The Faculty of CEG comprises 28 research groups in the following seven departments: Materials Mechanics Management & Design, Engineering Structures, Geoscience and Engineering, Geoscience and Remote Sensing, Transport & Planning, Hydraulic Engineering and Water Management.