Upcoming trends in various wireless applications will necessitate a major paradigm shift in terms of the data rates, coverage during high mobility, low latency, and ubiquitous always-on broadband network coverage. For today’s 5G networks, the objective is to achieve up to a few Gigabits/s data rates at lower mm-wave spectrum (~30 GHz). Subsequent evolutions will utilize sub-THz spectrum, i.e. radio frequencies above 100 GHz, to reach a data rate up to 100 Gigabits/s, and to support many other unprecedented features and functionalities. Even though the frequency spectrum is less crowded in the sub-THz frequency range, there are plenty of technological challenges in designing RF hardware around 100 GHz.

The Figure below shows a system block diagram of an RF front-end intended for higher mm-wave frequencies (also known as Extremely High Frequencies, EHF). In addition to proper fuctionality of each block, the transistions or interfaces between the blocks are of equal importance. If there is too much loss or mismatch between the sub-units, all performance is lost.

A communication or radar system is on lowest level characterized by its power budget, noise level, linearity and frequency stability. These can all be broken down into more detailed aspects or aggregated into higher level performance criteria. Since the blocks and components of the systems will have variation of their performance, it will be necessary to calibrate the system for amplitude and phase through each pathway. Mainly, this should be done over-the-air, but possibilities of including test ports and feedback loops should also be considered.

The project includes reading up on the research field, investigating and inventing calibration schemes and evaluating the resulting and needed performance after calibration. Close interaction with industry and academia involved in development and research within the field is expected.

Goals of the project are to describe reasonable, realistic calibration methods for today's state-of-the-art technology, to analyze the impact for the systems and find the most important limitations and trade-offs.

We are looking for a Chalmers University of Technology student with knowledge and interest in communication, signal processing and RF aspects. You need to be independent, self-sufficing, communicative and humble.