Version 1.0 Rev B - 08/00
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shadowing
Shadowing is a form of diffraction that is typically caused when antennas are mounted too
close to a structure, and they lose a portion of the signal lobe due to reflection. The receive
antenna is in a
shadowed
area. To minimize shadowing, ensure that there is adequate
height above when mounting antenna equipment to a structure.
SNMP
Simple Network Management Protocol. A protocol you can use to remotely manage a
network element by polling, setting terminal values, and monitoring network statistics and
events. It is the de-facto internet work management standard, designed to provide a
mechanism for the exchange of management information in a TCP/IP-based Internet
environment.
spread spectrum
Any of a group of modulation formats in which an RF bandwidth much wider than signal
bandwidth is used to transmit information, resulting in a greater immunity to noise
interference.
system gain
The maximum path loss that the system can support for usable data transmission.
system image file
The Hopper Plus 120-24 uses system image files to store system configuration settings.
The default system image file is called factory-image and is when the Hopper Plus is
first powered up.
T
telnet
An Internet communications protocol that enables a computer to function as a terminal
working on a remote computer. A computer with a network connection to a Hopper Plus
120-24 system can Telnet to any of the (configured) Hopper Plus 120-24 units and access
their configuration menus.
throttling
Throttling limits the amount of data that a remote station passes.
U
uptilt
See downtilt.
X
XPD (Cross-Polarization Discrimination)
Refers to polarity and Cross-Polarization Discrimination. Antennas have an associated
polarity, which is the orientation of the radiating element with respect to earth. Antennas
are usually described as being vertical, horizontal, or circularly polarized. The polarity of
all antennas used in a system must be the same. XPD specifies the amount of signal
