Public land radio is a _____ system.

Mobile telephones offer ____ transmission.

Which of the following is an example of a wireless communication technology?

Which of the following is NOT a type of wireless communication?

____ is equipment which converts electrical signal back to the physical message.

Mobile telephones are ____ systems.

Mobile telephones are safeguarded with _____ for privacy reason.

In communication system, Noise is most likely to affect the signal 

Which device is primarily used to connect different networks?

Amateur radio covers ____ frequency band.