A radar based mass movement sensor for automotive security applications

Theft of and from vehicles will be reduced by the ability to detect movement of persons within the vehicle cabin, as perimetric protection may not always be sufficient to trigger an alarm. A mass movement sensor which is reliable, robust and undetectable is required, to operate in conjunction with an effective alerting device. Whilst ultrasonic detection systems have become the technology norm for this application, they suffer from serious disadvantages in respect of false alarm rate due to their susceptibility to environmental changes when deployed within a vehicle. Here, the author describes movement sensors based on Doppler radar principles which do not exhibit false alarm behaviour and can be used in open vehicles