The Radio Frequency Intruder Detection system is one of a range of technologiesdeveloped by Geoquip to offer complete protection in places where uninvited guestsneed to be discouraged. It is discreet and therefore ideal for proximity detection, wherean intruder will walk unknowingly into its invisible field. The strategically placedtransmitters and receivers will cover the vulnerable area with a blanket of radiofrequency rays linked to an analyzer.At its heart, RAFID has two specially designed cables - one transmitting a radio wave,the other receiving that wave. Changes in the amount of signal passing between thetransmitter cable and receiver cable are analyzed by a signal processor whichdetermines whether these changes are due to the presence of a human.