Wireless communication systems 18 Computer networks 12 Design and construction 12 Mathematical models 9 Security measures 8 Mobile communication systems 7 Signal processing 7 Wireless sensor networks 7 Computer network protocols 6 Quality control 6 Radio frequency identification systems 6 Routers (Computer networks) 6 Telecommunication 6 Artificial satellites in telecommunication 5 Computer security 5 Digital techniques 5 Microwaves 5 Optical communications 5 Speech processing systems 5 Attenuation 4 Code division multiple access 4 Computer algorithms 4 Computer engineering 4 Fuzzy logic 4 Metal oxide semiconductors, Complementary 4 Microwave communication systems 4 Neural networks (Computer science) 4 Quantum communication 4 Rain and rainfall 4 Servomechanisms 4