Human occupancy detection (HOD) in an enclosed space, such as indoors or inside of a
vehicle, via passive cognitive radio (CR) is a new and challenging research area. Part of the
difficulty arises from the fact that a human subject cannot easily be detected due to spectrum
variation. In this paper, we present an advanced HOD system that dynamically reconfigures
a CR to collect passive radio frequency (RF) signals at different places of interest. Principal
component analysis (PCA) and recursive feature elimination with logistic regression (RFE …

The usage of passive RF data shares some of the same traits with passive radar systems in
which no actively transmitted signals are required, and the object is detected through third
party emitters. In addition to that, both passive radar and the proposed solution have low
power consumption and are difficult to detect. Both solutions can be used to find a moving
target and monitor an air space when the target is not visually observable. Because the
solutions do not use an active emitter and only collect passive RF signals from the …