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HYBRID NETWORKS TERRESTRIAL PACKET/SATELLITE Trucking company Boyle Transport makes it crystal clear: you should be able to pick a radio or cellular based system for regional service and satellite for long haul, but be able to use the same provider. 1 This is the goal of most hybrid offerings, though satellite may well be avoided in favor of an alternative technique such as circuit switched cellular. 7.1.1 AMSC/ARDIS Multimode System In March 1990 Rockwell announced that it was developing a satellite-based vehicle location and two-way data system.2 Rockwell s plan was to lease L-band capacity from AMSC, which was leasing time from InMarSat | The Wireless Data Haadbaak Fourth Edition. James F. DeRose Copyright 1999 John Wiley Sons Inc. ISBNs 0-471-31651-2 Hardback 0-471-22458-8 Electronic 7 HYBRID NETWORKS 7.1 TERRESTRIAL PACKET SATELLITE Trucking company Boyle Transport makes it crystal clear you should be able to pick a radio or cellular based system for regional service and satellite for long haul but be able to use the same provider. 1 This is the goal of most hybrid offerings though satellite may well be avoided in favor of an alternative technique such as circuit switched cellular. 7.1.1 AMSC ARDIS Multimode System In March 1990 Rockwell announced that it was developing a satellite-based vehicle location and two-way data system.2 Rockwell s plan was to lease L-band capacity from AMSC which was leasing time from InMarSat. Rockwell concentrated on the vehicular terminals and communications hardware. It began to develop a new control center for switching data between customer s headquarters and their vehicles. Rockwell saw its competition as OmniTRACS then only 7500 units and Geostar now defunct . Rockwell s perceived edge were its customers who had already installed 80 000 TripMasters. Since Rockwell s product was not yet ready indeed it was still debating whether or not Loran-C was the best way to go it purchased the first two year s devices from Canadian Aeronautics CAL . The plan was to resell each unit for 3500 its own device was estimated to be 2500. This was markedly cheaper than the 4000- 5000 charged by Geostar and OmniTRACS. However the Rockwell airtime costs were estimated to be 50- 60 per month quite a bit more than the 35- 45 charged by Geostar and OmniTRACS.3 80 7.1 TERRESTRIAL PACKET SATELLITE 81 As with many acts of bravado the world did not accommodate itself to Rockwell s goals. After long delays Rockwell finally had the Pro2000 product in April 1993 for 4000. The airtime price was 60 for 15 000 bytes 4 per kilobyte .4 Rockwell s device sold slowly 3000 units over six months. .
