Joint Millimeter-Wave Sensing and Wireless Data Transmission Using Modulated Thermal Noise

Millimeter-wave (MMW) sensing technology is widely used in various fields, such as medical diagnosis, security scanning, atmospheric science, and astronomy. In many practical applications, it is also necessary to share information (e.g., commands or warnings) while sensing, which requires additional data transmission systems. In this article, a multifunctional joint technique that can simultaneously realize MMW sensing and data transmission using the same hardware system is proposed. The concept is based on passive MMW imaging and amplitude-modulated noise illumination that carries specified modulation for data transmission. Since the emitted modulated noise and ambient noise are incoherent signals with broadband and low power spectrum density, the receiver of data transmission differs from the traditional coherent receiver by using a radiometer for incoherent detection of wideband weak noise signals. So, the proposed joint system is inherently covert against interception. Meanwhile, the sensing receiver can capture the intrinsic ambient noise and the emitted noise, allowing us to use algorithms to separate these two components based on the modulation information, thereby extracting both active and passive information about the scene. By developing a principle prototype system, we have verified this concept in the W-band, while completing the transmission of image data and the detection of “cold,” “hot,” trihedral corner reflectors, and absorbing-material objects.