the aim of this work is to present a new methodology,
based on vector and geometrical techniques, for determining the
position of an intruder in a residence (3D problem). Initially,
modifications in the electromagnetic responses of the environment,
caused by movements of the trespasser, are detected. It is worth
mentioning that slight movements are detected by high frequency
components of the used pulse. The differences between the signals
(before and after any movement) are used to define a sphere and
ellipsoids, which are used for estimating the position of the invader.
In this work, multiple radars are used in a cooperative manner.
The multiple estimates obtained are used to determine a mean
position and its standard deviation, introducing the concept of
sphere of estimates. The electromagnetic simulations were
performed by using the FDTD method. Results were obtained for
single and double floor residences.
