FOR PURPOSES OF THIS REPORT, THE CARGO SECURITY SYSTEM WAS TESTED UNDER CONTROLLED CONDITIONS TO VERIFY THE OPERATION OF SYSTEM ELEMENTS. AS A RESULT OF THE PILOT TEST, CHANGES WERE MADE IN THE SYSTEM TO IMPROVE PERFORMANCE. THE EQUIPMENT MOUNTED IN THE TRUCK IS BEYOND THE DRIVER'S CONTROL. CARGO SECURITY COMMUNICATION TO AND FROM THE TRUCK IS ON A COMMON COMMUNICATION LINK SEPARATE FROM THE VOICE CHANNEL. THE LOCATION SUBSYSTEM INCLUDES THE HYBRID PHASE LOCK LOOP AND THE SIGNPOST PROXIMITY EQUIPMENT. THE BASE STATION AND TRUCKING COMPANY DISPATCH STATION ARE CONNECTED BY TELEPHONE LINES WITH A MODEM FOR EACH COMPANY. THE TRANSMISSIONS FROM THE TRUCK ARE EVENT DRIVEN....BDS