Multi-Channel Access Solutions for 5G New Radio

The arrival of 5G New Radio Release-15 opens the door for introducing Radio Resource Management solutions targeting enhanced mobile broadband and ultra-reliable low latency communication service classes. Multi-Channel Access is a family of such multi-service solution, which enables a user equipment to aggregate radio resources from multiple sources, either from the same or from different nodes. The objective is multi-fold; throughput enhancement through access to a larger bandwidth, reliability improvement by increasing the diversity order and/or coordinated transmission/reception, or more flexible load balance and performance increase by decoupling the downlink and the uplink access points. This paper presents a number of multi-channel solutions for the 5G New Radio multi-service scenario. In particular, we discuss throughput enhancement and latency reduction concepts like multinode connectivity, carrier aggregation, downlink-uplink decoupled access and coordinated multi-point connectivity. A number of design challenges for these concepts are then highlighted, followed by novel solution proposals. All the proposed solutions are numerically validated, and found to result in significant performance gains over state-of-the-art solutions; for example, our proposed component carrier selection mechanism leads to an average median throughput gain of around 66% by means of an implicit load balance.