Cellular networks with D2D links are increasingly being explored for mission-critical applications (e.g., real-time control and AR/VR) which require predictable communication reliability. Thus it is critical to control interference among concurrent transmissions in a predictable manner to ensure the required communication reliability. To this end, we propose a Unified Cellular Scheduling (UCS) framework that, based on the Physical-Ratio-K (PRK) interference model, schedules uplink, downlink, and D2D transmissions in a unified manner to ensure predictable communication reliability while maximizing channel spatial reuse. UCS also provides a simple, effective approach to mode selection that maximizes the communication capacity for each involved communication pair. UCS effectively uses multiple channels for high throughput as well as resilience to channel fading and external interference. Leveraging the availability of base stations (BSes) as well as high-speed, out-of-band connectivity between BSes, UCS effectively orchestrates the functionalities of BSes and user equipment (UE) for light-weight control signaling and ease of incremental deployment and integration with existing cellular standards. We have implemented UCS using the open-source, standards-compliant cellular networking platform OpenAirInterface, and we have validated the UCS design and implementation using the USRP B210 software-defined radios in the ORBIT wireless testbed. We have also evaluated UCS through high-fidelity, at-scalemore »
End-to-end Simulation of mmWave Out-of-band Backhaul Networks in ns-3
In this paper, we focus on the end-to-end simulation of millimeter-wave (mmWave) out-of-band backhaul networks in ns-3. We first introduce a design for an out-of-band backhaul module in ns-3. A custom backhaul network device is proposed that can be added to nodes to enable out-of-band backhaul transmissions. Since the new backhaul module is still under development, we extended the existing mmWave integrated-access-and-backhaul (IAB) module to enable mmWave out-of-band backhaul simulation and produce some preliminary results on throughput performance. We also modified the existing scheduler in the IAB module to support customizable scheduling for logical links in out-of-band backhaul networks. We used the customizable scheduler to implement an optimal scheduling algorithm from prior work and demonstrate that it increases throughput performance by up to 40% in certain scenarios.
- Award ID(s):
- Publication Date:
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- Proceedings of the 2019 Workshop on Next-Generation Wireless with ns-3
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- Sponsoring Org:
- National Science Foundation
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