Cellular telephone systems 242 Wireless communication systems 85 Mobile communication systems 72 Computer programs 21 Wireless LANs 20 Operating systems (Computers) 18 Design and construction 17 Personal communication service systems 17 Internet telephony 15 Radio 15 Detectors 14 Adaptive antennas 13 Global system for mobile communications 13 Broadband communication systems 12 Interference 11 Data processing 9 C++ (Computer program language) 8 Code division multiple access 8 Equipment and supplies 8 Radio frequency allocation 8 Radio wave propagation 8 Computer simulation 7 Convergence (Telecommunication) 7 Quality control 7 Standards 7 Telecommunication systems 7 Cellular telephone services industry 6 Technological innovations 6 Wireless Internet 6 Cellular telephones 5