User Manual

AirLink VoiceXtender VX64 Modem Installer’s Guide
Glossary
C-2 Rev. A - 8/97
Antenna A transmitting or receiving device for radiated waves. The
antenna acts as a form of matching transformer for waves along a
line and waves in space so that the maximum transfer of energy
can be achieved.
Antenna Gain Antenna gain is a measure of the efficiency of an antenna
compared with the efficiency of a standard reference antenna.
The efficiency is measured in terms of the power radiated or
received in a given direction as compared with the standard
under the same conditions.
Asynchronous Data
Transmission
The transmission of data in which each character is a self-
contained unit with its own start and stop bits and intervals
between characters may be uneven.
Bit Error Rate (BER) The measure of the frequency of errors in a digital transmission.
Burst Timing A form of timing in which the receiving device is synchronized to
the transmitting device by receiving bursts of data.
Cable Loss The amount of signal attenuation (loss) for a particular type of
cable of a given length.
Channel A specified frequency slot within the specified frequency band
used for transmission.
DCE Data Circuit Equipment—a communications device that
establishes, maintains, and terminates a session on a network.
DTE Data Terminating Equipment—a communications device that is
the source or destination of signals on a network.
Fade Margin The measure of how much signal attenuation the system can
endure without dropping below the minimum desired BER level.
Free Space Path Loss The loss of power of a radiated signal as it travels through space.
Full Duplex Transmission in two directions simultaneously.
Half Duplex A circuit designed for data transmission in both directions, but not
at the same time.
Handshake Signal The series of signals between a computer and another peripheral
device (for example, a modem) that establishes the parameters
required for passing data.