FINDER (Finding Individuals for Disaster and Emergency Response) is a portable human life detector developed by NASA's Jet Propulsion Laboratory for the Department of Homeland Security, Science and Technology Directorate. It is a low-power multichannel CW-FM radar operating at 3 GHz. During a 30 second search period, it uses a simple radar to measure small motions of things within the rubble. The detected signals are digitized, filtered, and processed by a nonlinear search algorithm to find candidate signals. The detected signals are processed to determine whether the motions are characteristic of humans, as opposed to animals or mechanical artifacts. To do this, the signal parameters are evaluated against a set of criteria for “humanness,” such as showing a coupling between heart rate variation and respiration. The results of the analysis are displayed for the user on a ruggedized laptop computer.