Over-the-Air Computing for Wireless Data Aggregation in Massive IoT

Abstract

Wireless data aggregation (WDA), referring to aggregating data distributed at devices (e.g., sensors and smartphones), is a common operation in 5G-and-beyond machine-type communications to support the Internet of Things (IoT), which lays the foundation for diversified applications such as distributed sensing, learning, and control. Conventional WDA techniques, which are designed in a task-agnostic manner separating communication and computation, encounter difficulty in accommodating the massive access under the limited radio resource and stringent latency constraints imposed by emerging applications or tasks (e.g, auto-driving). To address this issue, over-the-air computation (AirComp) is being developed as a new task-oriented solution for WDA by seamlessly integrating communication and computation. By exploiting the waveform superposition property of multiple access channels, AirComp turns the air into a computer for computing and communicating functions of distributed data at many devices, thereby allowing low-latency WDA over massive IoT networks. In view of growing interest in Air-Comp, this article provides a timely overview of the technology by introducing basic principles, discussing advanced techniques and applications, and identifying promising research opportunities.