QoS guaranteed radio resource scheduling in stand-alone unlicensed MulteFire

Abstract

Increase in voice and data traffic has recently prompted cellular operators to consider deploying LTE-like systems in the unlicensed spectrum as an option to meet their customer requirements. This has led to industry-proposed specifications for unlicensed band access, namely LTE enhanced Licensed Assisted Access (LTE-eLAA), LTE Unlicensed (LTEU)/MulteFire (MF). In this paper we focus on MF, which is an extension to the LTE specification that operates entirely in the unlicensed band. It employs a flexible frame format that enables adaptive allocation of subframes for uplink and downlink resources, unlike the rigid (or) fixed frame format used in eLAA. We study and evaluate the potential of a MF network in terms of its flexible resource allocation to ensure Quality of Service (QoS) guarantees to users. Exploiting MF’s flexible allocation, we propose a scheduling model that utilizes a satisfaction function which guarantees transmission opportunities to users that are close to their deadline (i.e., reward to users transmitting closer to their deadlines and penalty to users transmitting after their deadlines). Compared to eLAA our proposed MF scheduling algorithm achieves better performance for a dense user deployment. We corroborate the analysis by performing system level simulations in ns-3 and demonstrate good agreement between analysis and simulation with respect to latency and packet-drop metrics.