The overall targeted concept in Flex5Gware is that of performing research on and demonstrating key building blocks to enable reconfigurable HW platforms and HW-agnostic SW platforms taking into account increased capacity, reduced energy footprint, as well as scalability and modularity.
The development of this proposed concept entails many system design challenges that will be solved through disruptive technologies. Each technology proposed in Flex5Gware is contributing, at least, to one of the following goals with respect to 5G communication platforms:
- To improve the energy and spectrum efficiency.
- To improve the modularity and flexibility (which implies increased reconfigurability and scalability).
The Flex5Gware consortium has identified four groups of technologies that are necessary to reach these goals (each one of these groups will correspond to a different work package, as detailed in Section 3):
- RF front-ends and antennas
a. RF subsystems for multiband and reconfigurable operation and maximized total bandwidth (PAs, LNAs, frequency converters, filters, mixers) operating at bands below 6 GHz. Advanced semiconductor materials GaN-on-Si and GaN-on-SiC
b. Active low-cost antennas (compact, conformable both for NE and UE) operating below 6 GHz. Based on SIW technology
c. Chip frequency generation in 28 nm CMOS for mmWave bands
d. Joint antenna-power amplifier for mmWave
e. RF impairment analysis for mmWave
- Mixed-signal technologies
a. Broadband A/D and D/A converters for multiple band operation and large bandwidth
b. Power consumption reduction and linearization techniques based on joint analogue and digital processing (e.g., envelope tracking, predistortion)
c. High-bandwidth antenna links based on new fibre-to-the antenna transceiver subsystem technology
d. Full duplex operation
- Digital front-end and HW/SW function split
a. Digital HW architectures for the processing of new 5G waveforms.
b. Advanced receiver architectures (encompassing flexible and efficient MIMO decoders for user equipments and multi-objective optimized FEC decoders).
c. Flexible HW/SW partitioning and other architectures for modularity
d. Abstraction of transceiver HW to be supported in 5G programmable terminals (this includes sensor and location awareness integration in the HW)
- SW modules and functions
a. Reconfigurable, reprogrammable SW architecture with appropriate interface abstractions for flexible control and management mechanisms across heterogeneous wireless devices and access networks.
b. Feedback-loop analysis/muti-node coordination for “over the air” real-time operation and update of nodes, targeting reliability, delay, and “safe fail” operation.
c. New sets of SW tools consisting of libraries and modules in order to support new SW functions, e.g. virtualized base band units (BBU) and reconfigurable layers, offering greater degree of flexibility in terms of configurability.
d. Flexible, effective and efficient resource allocation mechanisms in a centralized RAN environment, that allow an operator to enhance performance and save energy.
Some of these technologies will be directly demonstrated as stand-alone PoCs, while some others will be combined/integrated to create integrated PoCs. The following figure provides a graphical (and intuitive) representation of the Flex5Gware concept.