Synthetic Aperture Communication: Principles and Application to Massive IoT Satellite Uplink

TL;DR

This paper introduces synthetic aperture communication (SAC) for satellite uplink, enabling precise direction estimation and interference mitigation, which supports massive IoT connectivity with low power and high reliability.

Contribution

It pioneers the application of synthetic aperture principles to satellite communication, demonstrating effective interference management and low-power operation for IoT devices.

Findings

Achieves block error rates below 0.1 at -10 dBm transmission power.

Demonstrates spatial separation and localization of multiple IoT devices.

Validates SAC's potential for massive IoT connectivity in non-terrestrial networks.

Abstract

While synthetic aperture radar is widely adopted to provide high-resolution imaging at long distances using small arrays, the concept of coherent synthetic aperture communication (SAC) has not yet been explored. This article introduces the principles of SAC for direct satellite-to-device uplink, showcasing precise direction-of-arrival estimation for user equipment (UE) devices, facilitating spatial signal separation, localization, and easing link budget constraints. Simulations for a low Earth orbit satellite at 600 km orbit and two UE devices performing orthogonal frequency-division multiplexing-based transmission with polar coding at 3.5 GHz demonstrate block error rates below 0.1 with transmission powers as low as -10 dBm, even under strong interference when UE devices are resolved but fall on each other's strongest angular sidelobe. These results validate the ability of the proposed scheme to address mutual interference and stringent power limitations, paving the way for massive Internet of Things connectivity in non-terrestrial networks.