Rectenna or rectifying antenna critical technology for wireless power systems, powering military drones, and receiving solar power from satellites

Over the past two decades, many wireless systems have been developed and widely used around the world. The most important examples are cellular mobile radio and Wi-Fi systems. Just like radio and television broadcasting systems, they radiate electromagnetic waves/energy into the air but a large amount of the energy is actually wasted, thus how to harvest and recycle the ambient wireless electromagnetic energy has become an increasingly interesting topic.