Mobile communication systems Wireless communication systems IEEE 802.16 (Standard) 5 Roaming (Telecommunication) 5 Wireless LANs 5 Broadband communication systems 3 Equipment and supplies 3 Wireless metropolitan area networks 3 Code division multiple access 2 Design and construction 2 Management 2 Mobile computing 2 Packet switching (Data transmission) 2 Routing protocols (Computer network protocols) 2 Absorption 1 Access control 1 Ad hoc networks (Computer networks) 1 Adaptive antennas 1 Antennas (Electronics) 1 Cache memory 1 Cell phone systems 1 Cell phones 1 Cellular telephone services industry 1 Cellular telephone systems 1 Communication systems 1 Computer networks 1 Energy harvesting 1 Enterprise application integration (Computer systems) 1 Global system for mobile communications 1 Instant messaging 1