The problem for mmWave systems at 5G and 6G
Future hand-held mobile communications systems are expected to deliver thus far unimagined user bandwidths and responsiveness. This requires new radio systems to be created to cater for the frequency bands expected to host such vast communications bandwidths – the mmWave bands.
These bands extend from 26GHz upwards and prior to 5G had not been used for mobile systems (though were common for backhaul). However, key problems with using these bands remain, relating to their energy consumption (hence mobile battery life) and their hardware cost, as well as system complexity.
Figure 1, Contemporary mmWave SDR based system power and cost.
It is well known that modern high bandwidth radio systems make significant use of digital signal processing and SDR, which imposes a significant hardware cost and energy demand. From the above figures, based on our analysis, we see that such architectures impose a significant hardware cost and energy demand. Using present technologies, this could result in mobile mmWave product battery life of less than 40 minutes!
Techniques to help address these issues form the core of my Fellowship. A holistic and multidisciplinary approach is proposed that will consider energy-efficient and appropriate use of RF / Analogue / Digital techniques to solve the overall radio communications need. This spread of disciplines and techniques (biased towards RF hardware) has been the hallmark of Eddie's professional career prior to moving to academia and is now sorely needed for future mmWave systems. The figure below shows the concept architecture of the multidisciplinary system that will be investigated.
Figure 2, Exploratory architecture for mmWave & SDR (green areas investigated in the Fellowship).
The project has been split into key areas of high novelty, representing the focus of our mmWave research whilst also supporting multidisciplinary techniques: -
- Antenna arrays
- RF mixers circuits
- RF oscillator circuits
- Software Defined Radio & Signal Processing
- Cognitive Radio
- Artificial Intelligence at the physical layer
- Demonstration Platforms
The research will be conducted by Eddie and his research group, reporting findings as they go along. A key aspect will be the realisation of concepts as test chips which they will test and demonstrate.