Ultra-Reliable Device-Centric Uplink Communications in Airborne Networks: A Spatiotemporal Analysis

TL;DR

The paper tackles data aggregation for IoT in large-scale airborne networks by contrasting a device-centric URDC-UL approach with a stationary SUC-UL baseline. It develops a spatiotemporal model using stochastic geometry and queueing theory to capture UAV mobility, interference, channel LOS/NLOS, and temporal traffic, and derives transmission-success probabilities and meta-distributions for both schemes. Key contributions include a mobility-aware interference model, trajectory-based scheduling analysis, Green-energy considerations, and insights into the hover-travel time trade-off affecting reliability, rate, delay, and fairness. The results show URDC-UL can achieve ultra-reliable links at low device transmit power, delivering higher reliability and energy efficiency with more uniform device experience, informing design choices for UAV-assisted IoT networks.

Abstract

This paper proposes an ultra-reliable device-centric uplink (URDC-UL) communication scheme for airborne networks. In particular, base stations (BSs) are mounted on unmanned aerial vehicles (UAVs) that travel to schedule UL transmissions and collect data from devices. To attain an ultra-reliable unified device-centric performance, the UL connection is established when the UAV-BS is hovering at the nearest possible distance from the scheduled device. The performance of the proposed URDC-UL scheme is benchmarked against a stationary UAV-centric uplink (SUC-UL) scheme where the devices are scheduled to communicate to UAV-BSs that are continuously hovering at static locations. Utilizing stochastic geometry and queueing theory, novel spatiotemporal mathematical models are developed, which account for the UAV-BS spatial densities, mobility, altitude, antenna directivity, ground-to-air channel, and temporal traffic, among other factors. The results demonstrate the sensitivity of the URDC-UL scheme to the ratio between hovering and traveling time. In particular, the hovering to traveling time ratio should be carefully adjusted to maximize the harvested performance gains for the URDC-UL scheme in terms of link reliability, transmission rate, energy efficiency, and delay. Exploiting the URDC-UL scheme allows IoT devices to minimize transmission power while maintaining unified reliable transmission. This preserves the device's battery and addresses a critical IoT design challenge.

Figures (17)

• Figure 1: The SUC-UL scheme for $N=6$ (filled circles in blue: UAV fixed locations, red: active devices, black: inactive devices).
• Figure 2: The URDC-UL scheme for $N=6$ (filled circle in blue: traveling UAV, red: UAV hovering close to an active device, and arrows show the trajectory).
• Figure 3: Average traveling distance at different cell radii.
• Figure 4: Average success probability for both models.
• Figure 5: Success probability of URDC-UL model for the suburban area at different $\eta$ values.

Theorems & Definitions (8)

• Remark 1
• Lemma 1
• Theorem 1
• Lemma 2
• Theorem 2
• Proposition 1
• Remark 2
• Theorem 3