Over-the-Air Computation via Broadband Channels

Over-the-air computation (AirComp) has been recognized as a low-latency solution for wireless sensor data fusion, where multiple sensors send their measurement signals to receiver simultaneously computation. Most existing work only considered performing AirComp over single frequency channel. However, network with massive number of nodes, channel may not be sufficient accommodate the large sensors, and performance will very limited. So it is highly desirable have more channels large-scale systems benefit from multi-channel diversity. In this letter, we propose an ${M}$ -frequency system, each selects subset frequencies broadcasts its signal these under certain power constraint. We derive optimal sensors’ transmission receiver’s processing methods separately, develop algorithm joint design achieve best performance. Numerical results show that increasing one can improve by threefold compared single-frequency case.