9531396 Jacobsmeyer This Small Business Innovation Research Phase II project investigates a channel hopping mobile data base station for use on cellular radio networks. Because voice cellular radio systems must maintain low blocking probabilities, more than 20% of cellular channel capacity is unused, even during the busy hour. A packet radio system can capture this unused capacity by hopping between idle voice channels, working independently of the voice base station and the cellular telephone switch. To optimize performance, the mobile data base station should select the idle channel with the least co-channel interference. By doing so, the base station will maximize the carrier-to-interference ratio at the mobile terminal and maximize throughput when automatic repeat-request protocols are used. For example, if the offered voice traffic at an 18-channel sector is 9 Erlangs, the data base station can achieve a throughput improvement of 42% and a coverage area increase of 28%. This study extends the Phase I research by collecting interference data from an actual cellular radio system and testing new hopping algorithms against this data. The firm will also use the data to develop better models of the cellular voice multiple access system and co-channel interference. If successful, the project will result in a working prototype of a smart channel hopping radio receiver and controller that will substantially increase the throughput and geographical coverage of the Cellular Digital Packet Data (CDPD) system. The principal commercial applications of this research are wireless multiple access communication networks, including cellular radio, mobile satellite, and wireless local area networks. The primary benefit of the proposed research is more economical use of packet radio base stations, resulting in more affordable mobile data service for the U.S. consumer.
