Novel BWP Schemes for Multi-Numerology and Multi-Slice Radio Access Networks

With Fifth Generation (5G) mobile networks, the concept of Bandwidth Part (BWP) was introduced to support flexible Orthogonal Frequency-Division Multiplexing (OFDM) subcarrier spacing, also deemed numerologies to achieve lower latency for delay stringent services. A BWP is a set of contiguous Physical Resource Blocks (PRBs) associated to a numerology which is scanned by the User Equipment (UE) to retrieve or submit its data. Additionally, a UE can be connected to multiple slices or services simultaneously thanks to slicing which was introduced in 5G to ensure isolation among multiple co-existing services on the same network. In this context, a BWP switch is required for such users when their services use different numerologies. In this paper, we propose three innovative methods to optimize the BWP Switching process for users connected to multiple slices where both enhanced Mobile Broadband (eMBB) and Ultra Reliable Low Latency Communications (URLLC) services are considered. These mechanisms rely on the modification of the Downlink Control Information (DCI) which carries the BWP indicator for users as well as the BWP Inactivity Timer that triggers a Default BWP switch. The performance evaluation demonstrates the high efficiency of our solutions in terms of latency for URLLC services, throughput for eMBB services and number of DCIs scanned compared to the baseline approach.