SPEED-5G demos on novel spectrum resource management solutions
The SPEED-5G project consortium demonstrated its novel solutions for spectrum resource management to an interested audience at its workshop in London on 7th March 2018. The descriptions and videos below convey a detailed impression of the demos.
Demo 1: Combination of centralised and decentralised radio resource management with a novel MAC protocol for higher capacity in small cells
This demo shows how the SPEED-5G outcomes can be implemented to optimize the usage of spectrum resources and deliver the best QoS in dense heterogeneous networks in order. The demo relies on the hierarchical RRM framework which mixes both distributed and centralized RRM agents (dRRM and cRRM, respectively) and two multi-RAT small cells. Depending on the traffic load, the dRRM agent of a small cell may decide to offload some traffic on a channel of the 5 GHz unlicensed band, and notifies the cRRM agent about this decision. In order to avoid interference on the 5 GHz band, cRRM provides the other cell with a spectrum mask which prevents from transmitting on the same channel. In this demo, the second cell implements a novel MAC protocol based on post-LTE waveform and capable of autonomously selecting the least interfered channel on the 5GHz band. Relying on a mandatory listen-before-talk procedure and a channel selection based on reinforcement learning, this MAC protocol is able to apply the guideline of the cRRM and determine the best possible channel to transmit data to UEs, avoiding interference from other coexisting systems like WiFi access points and stations.
Demo 2: Exploitation of heterogeneous spectrum resources through tight integration of multiple RATs at MAC layer
In order to efficiently exploit heterogeneous spectrum resources, a tighter integration of multiple RATs such as LTE, WiFi, and new 5G NR that allows efficient use of licensed, unlicensed and lightly-licensed resources, is required. In the enhanced dynamic spectrum access (eDSA) framework, proposed in SPEEd-5G, a tighter integration of multiple RATs is accomplished at the MAC level, based on a MAC-level split, where the MAC layer is divided into two sub-layers, namely, higher MAC (HMAC) and lower MAC (LMAC). The HMAC and layers above are common to all RATs, and the HMAC supports new functional modules for inter-RAT resource scheduling at MAC level, whilst there are separate LMAC and PHY entities corresponding to each RAT.
The objective of this demonstration is to highlight project innovations related to inter-RAT e.g. LTE and WiFi, resource aggregation and traffic steering/offload, based on MAC-split solution. The results of aggregation based on MAC-split will also be compared with 3GPP legacy LWA implementation, which are used benchmarks. The demo setup represents a collocated scenario where common LTE EPC is connected to a single PC hosting LTE and WiFi via a switch. On the small-cell side, for LTE, an extension of OpenAirInterface (OAI) is adopted with USRP providing RF interface while COTs WiFi AP is used for providing the corresponding RF interface. On the UE side, a dual-interface terminal is emulated using NI Chassis hosting the extended OAI protocol stack and COTs WiFi device.