Pioneering Cell-free Massive MIMO prototyping platform for Ultra-Reliable 6G Wireless Communication & sensing Systems

Motivated by the new era of automation and the explosion of the IoT, the future wireless connectivity landscape of 6G and beyond will feature low-complexity high-throughput, ultra-reliable, and low-latency wireless communication systems. Such stringent requirements make the radio access design very challenging and some fundamental performance/complexity tradeoffs must be made. An example of such requirements are packet error rate in motion of 10^-9 or lower with latency in the order of a few µs-ms. In building up such robust wireless systems, a radically new radio access architecture is needed consisting of a large number of distributed access nodes that cooperate to meet the target quality of service. Such cell-free massive MIMO systems allow channel hardening by coherently beaming and distributing signals towards the mobile terminals. Furthermore, it will bring high-resolution sensing capability alongside the communication functionality.

However, several challenges need to be addressed and require multi-dimensional co-optimization before such distributed systems become practical and reliable, for instance concerning fronthauling, functional split between centralized and distributed processing, distributed synchronization, multistatic sensing, end-to-end system architecture targeted to low-cost deployment, to name a few.

The goal of this PhD is to provide to design, prototype, validate, and optimize a limited-scale (up to 20 distributed nodes) proof-of-concept of a cell-free massive MIMO radio access and sensing system in the field that can be efficiently scaled up for higher performance. Leveraging the recent advances within imec on FPGA SDR openwifi reference design (https://github.com/open-sdr/openwifi), a Linux mac80211 compatible full-stack IEEE802.11/Wi-Fi design, the Ph.D. student will have the opportunity to extend the platform to build a holistic distributed MIMO system capable to offer extremely reliable coverage in real-life deployments with a focus on indoor professional environments.

Because of the multidisciplinary nature of this Ph.D. research, the Ph.D. candidate will be part of a large IMEC team working on the research, implementation, and prototyping of future communications & sensing systems: experts in digital, analog, and mm-wave ASIC design, wireless/radar communications systems, PHY processing, MAC and higher layers, machine learning, and optimization. This is a unique opportunity to design, build, and validate breakthrough technology for future 6G wireless communication systems.

The Ph.D. candidate is expected to have a keen interest in wireless communication principles and protocols, and PHY and MAC layers in particular, and should have basic knowledge of MIMO signal processing and wired fronthauling systems such as 10GbE. Additional knowledge of system-level architecture, analog frontend, antenna arrays, and sensing is an advantage. Having hands-on experience in writing software and prototyping and having knowledge of C, C++, and Linux is a must. Already having experience with Verilog/VHDL implementation, which is an essential skill for this position, is an advantage.