The RTLS solution USES a matrix of sensors, one for each zone, to receive radio signals emitted from an active RFID tag affixed to the automobile's frame.

Omni-ID, a company that makes radio frequency ID tags, studied this reflection in their quest to create a tag that could be read through a metal mesh and in water.

It took less than 10k of JSP code to implement a set of tag files that produce the basic form elements: lists, text fields, radio buttons, check boxes, and submit buttons.