A survey on application in RF signal

RF signals have great advantages in environmental perception and is widely used in daily life. The device transmit wireless signals through transmitters, as these signals propagate through the medium, and reflected from different objects and people in space to the receiver. During this process, they carry rich environmental perception information, which is of positive significance to people's daily lives. In this survey, we first introduce the techniques of target sensing based on the sensing principle of radar. Secondly, we describe the relevant denoising techniques and principles. Then, we discuss the practical application requirements for RF signal related technologies, include indoor positioning, gesture recognition, health monitoring, identity authentication, behavior recognition, pose estimation, etc., and further explore the technical methods used in current popular applications. Finally, We discuss and analyze the advantages and disadvantages about these technologies and indicate the challenges and possible improvement directions in future.