Holographic radio architectures and signal processing for future high-throughput near-field communications

Driven by new emerging applications such as augmented reality, virtual reality, backhauling, and broadband access, the future wireless connectivity landscape towards 6G and beyond will support a wide a range of applications with very-high-throughput requirements. Such stringent requirements make the radio access design very challenging. The traditional approaches to increase the wireless data rate are increasing the bandwidth and resorting to multi-input, multi-output (MIMO) techniques. The former is not scalable beyond a few GHz of bandwidth and the latter is often impossible in the sub-THz bands that do not feature rich multipath, which is needed to have a significant channel rank.

A completely different approach, yet largely unexplored, is to resort to MIMO near-field communications, dubbed as holographic radio. The near-field propagation can hold up to a significant range especially in high-frequency bands. Because transmission in the near field implies spherical waves instead of plane waves, the channel matrix can have a high rank even for point-to-point links. Hence, high throughput can be achieved with moderate bandwidth even in a point-to-point link because multiple independent streams can be sent in parallel.

The goal of this PhD is to pioneer the next generation of MIMO near-field communications, shaping both its system architecture and physical layer algorithms. Your challenge is not just to make it work - but to redefine what’s possible by harnessing the unique properties of the near-field channel. If we combine this near-field channel with large bandwidths and multiple carrier frequencies we will have available in the next generation systems, we can come up with new antenna architectures that combine multi-band and multi-antenna near-field processing.

This research demands creativity and unconventional thinking. You will navigate complex trade-offs involving massive antenna arrays, computational feasibility, theoretical limits, and real-world hardware constraints. To start exploring this emerging domain, you will first develop a sophisticated simulation environment in Matlab and/or Python, based on a custom near-field channel model and including hardware non-idealities.

Beyond simulation, your work will provide deep insights into how near-field MIMO compares with existing paradigms like traditional diversity-based MIMO and LOS-MIMO. Your findings could redefine fundamental MIMO principles, with potential validation through real-world experiments on a communication testbed. If you're driven by curiosity, this PhD will give you the freedom and tools to innovate at the frontier of wireless technology.

As a PhD student, you will be part of a large IMEC team working on the research, implementation and prototyping of future communications systems composed of experts in digital, analog and mm-wave design, wireless communication systems, signal processing and machine learning, channel measurements and modelling. This is a unique opportunity to develop innovative, multi-disciplinary technology and shape future wireless networks. You will publish your research in top-level journals and conferences.