Asep Basic – Com With 100% Correct Answers Already Graded A+

What function of an electromagnetic wave is described in hertz? Frequency How is the relationship between wavelength and frequency? The lower the frequency, the longer the wavelength What is the method to change properties like amplitude or frequency of a periodic wave to convey a message to it called? Modulation What is meant by refraction of a radio wave? The change in direction of propagation of a wave due to change in its transmission medium What is meant by a duplex communication system? Telecommunication between two stations can take place in both directions simultaneously What aeronautical service is used between 118 - 137 MHz? Voice communication on the VHF band What is the purpose of the PTT button on a radio? To activate the radio transmitter What is SELCAL? A selective calling system that allows a ground radio operator to alert an aircrew that the operator wishes to communicate with that aircraft. What communication system allows a controller and an aircraft to communicate via data link text messages CPDLC What is the functionality of the radio receiver? Amplify and demodulate the signal to make it audible and pass it to the loudspeakers Which connections are normally used for ground-ground communication between ATS units? Telephone or intercom connections What is the message handling system used to exchange for instance flight plans and MET messages between ATS units called? AFTN What is an example of the aeronautical fixed telecommunication service? AMHS What is the functionality called that enables the VCS to select the receiver with best reception? BSS What is the storage requirements for recordings of voice communication? 30 days What technique is used to share several transmissions on the same transmission path? Multiplexing What is meant by circuit switching? A method that establishes a dedicated communication channel through the network before the nodes may communicate What is PENS? An IP-based aeronautical telecommunication network Which communication system uses the VDL Mode 2 data link? CPDLC What approximate range can be expected for line of sight propagation? Slightly beyond the visible horizon