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In this paper, we present a punctured scheduling scheme for efficient transmission of low latency communication (LLC) traffic, multiplexed on a downlink shared channel with enhanced mobile broadband traffic (eMBB). Puncturing allows to schedule eMBB traffic on all shared channel resources, without prior reservation of transmission resources for sporadically arriving LLC traffic. When LLC traffic arrives, it is immediately scheduled with a short transmission by puncturing part of the ongoing eMBB transmissions. To have this working efficiently, we propose recovery mechanisms for punctured eMBB transmissions, and a service-specific scheduling policy and link adaptation. Among others, we find that it is advantageous to include an element of eMBB-awareness for the scheduling decisions of the LLC transmissions (i.e. those that puncture ongoing eMBB transmissions), to primarily puncture eMBB transmission(s) that are transmitted with low modulation and coding scheme index. System level simulations are presented to demonstrate the benefits of the proposed solution.

Abstract-Ultra-reliable low-latency communications (URLLC) entail the transmission of sporadic and small packets, with low latency and very high reliability. Among many potential areas of optimization for URLLC, the problems of large delays during HARQ retransmissions, and inaccurate link adaptation as a consequence of the rapidly-varying interference conditions are studied. The former is addressed by reducing the TTI length and HARQ round-trip time, as compared to what is used in LTE; whereas including low-pass filtered interference information in the CQI report is also proved to have great potential. Extensive system-level simulations of the downlink performance show that the URLLC requirements, i.e. latencies below 1 ms and 99.999% reliability, are achievable at low load scenarios, whereas some performance degradation (1 -3 ms latency) is experienced at higher loads due to the increased queuing delay and inter-cell interference.

In this article, we present a holistic overview of the agile multiuser scheduling functionality in 5G. An E2E perspective is given, including the enhanced QoS architecture that comes with 5G, and the large number of scheduling related options from the new access stratum sub-layer, MAC, and PHY layer. A survey of the 5G design agreements from the recently concluded 5G Study in 3GPP is presented, and it is explained how to best utilize all these new degrees of freedom to arrive at an agile scheduling design that offers superior E2E performance for a variety of services with highly diverse QoS requirements. Enhancements to ensure efficient implementation of the 5G scheduler for different network architectures are outlined. Finally, state-of-the-art system level performance results are presented, showing the ability to efficiently multiplex services with highly diverse QoS requirements.