SMATV systems, consisting of one or more TV dish antenna, are installed on roofs of buildings to receive and transmit digital broadcast TV signals to the occupants of the buildings via cables.

Intercom and video door phone systems are used to manage calls made at entrances to buildings. Building occupants can communicate with visitors and verify their identities remotely, while allowing access to the visitors calling.

Nurse call systems are installed at hospitals and nursing homes to allow patients to notify health care staffs at the nurse's station of any emergencies. Once the systems are activated, health care staffs are required to visit the respective bed to determine if assistance is needed.

Public address systems amplify and broadcast acoustic sound source (e.g. music and voice messages) in public venues, making sound information audible over a large distance. 

Walkie-talkie allows users to communicate with each other via sending radio messages on a radio channel. This portable radio transceiver is suitable for internal communications within  businesses,  public safety,  military, outdoor recreation.