Mobile Sensor Systems for Intelligence Collection Using Doppler Shifting of Existing Communication Technology

Wireless communication signals can be used to detect human vital signs by measuring the Doppler shift of the returning signal. It is possible to use ambient wireless signals in the environment such as from cordless and mobile phones as a microwave Doppler radar to remotely and accurately measure an individual's pulse and respiration. Because of the range of typical frequencies involved, it is also possible for Doppler radar to measure vital signs through barriers such as drywall, cement and other non-metal construction materials. In addition, advanced signal processing techniques, combined with innovative hardware design could allow for not only detection of an individual through a wall but also the number and relative positions of multiple subjects. This Phase I effort will demonstrate the feasibility of sensing multiple individuals' vital signs through a wall and lay the groundwork for developing techniques to measure relative positions of multiple personnel through a wall.