Design and construction Equipment and supplies Wireless communication systems 15 Radio circuits 10 Aeronautics 6 Air conditioning 6 Heating 6 Ventilation 6 Airplanes 5 Integrated circuits 5 Radio 5 Systems engineering 5 Antennas (Electronics) 4 Very high speed integrated circuits 4 Microwave circuits 3 Airplanes, Military 2 Antennas 2 Cell phones 2 Chemical plants 2 Control 2 Dwellings 2 Heating and ventilation 2 History 2 Human-computer interaction 2 Miniature electronic equipment 2 Mobile communication systems 2 Planning 2 Telecommunication 2 Transmitter-receivers 2 Wearable computers 2