Millimeter-wave system technologies for wireless communications, imaging, and sensing

This paper describes millimeter-wave (MMW) system technologies for wireless communications, imaging, and sensing. MMW systems have advantages of large bandwidth and short wavelength, and recent progress in electronic and photonic device enables us to handle MMW signals easily at low cost. State-of-the-art MMW wireless communications systems can transmit over-10-Gbit/s data, and research on transmission characteristics is progressing steadily. MMW imaging systems using near-field dispersion can achieve high resolution, and they are starting to be used for non-destructive inspections of infrastructure. An MMW sensing system based on photonic technologies enable us to cover large bandwidths and is now being investigated for remote sensing of gasses in the fields of radio astronomy and disaster prevention.