User's Manual

User
AN-100U/UX Base Station
Manual
70-00058-01-04 Proprietary Redline Communications © 2010 Page 132 of 136 April 19, 2010
Term
Acron
ym
Definition
Megahertz
MHz
1,000,000 Hz
Modulation
-
Any of several techniques for combining user information with a
transmitter carrier signal.
Multicast polling
group
-
A group of subscribers that are assigned a multicast address for
the purposes of polling.
Multipath
-
The RF echoes created from radio signal reflections.
Network Time
Protocol
NTP
Protocol for synchronizing a set of network clocks using a set of
distributed clients and servers. It is implemented as Server on
BSC for time synchronization with subscribers and base stations.
Described in IETF RFC 958.
Non Line Of
Sight
NLOS
Completely obstructed path between two antennas.
NVRAM
Non-volatile RAM memory. Does not lose its data when power is
removed.
Non Real-Time
Priority
nrt-PS
The nrt-PS is designed to support non real-time service flows that
require variable size Data Grant Burst Types on a regular basis,
such as high bandwidth FTP. The service offers unicast polls on
a regular basis, which assures that the flow receives request
opportunities even during network congestion. The RedMAX
base station typically polls nrt-PS CIDs on an interval (periodic or
periodic) on the order of one second or less. The key service
elements are Minimum Reserved Traffic Rate, Maximum
Sustained Traffic Rate, Request/Transmission Policy, and Traffic
Priority.
Optical Line Of
Sight
OLOS
A clear direct path between two antennas, with obstructions
within the first Fresnel zone.
Orthogonal
Frequency
Division
Multiplexing
OFDM
Orthogonal frequency-division multiplexing (OFDM) is a method
of digital modulation in which a signal is split into several
narrowband channels at different frequencies. The technology
was first conceived in the 1960s and 1970s during research into
minimizing interference among channels near each other in
frequency.
In some respects, OFDM is similar to conventional frequency-
division multiplexing (FDM). The difference lies in the way in
which the signals are modulated and demodulated. Priority is
given to minimizing the interference, or crosstalk, among the
channels and symbols comprising the data stream. Less
importance is placed on perfecting individual channels.
Packet
-
A bundle of data organized in a specific way for transmission.
The three principal elements of a packet include the header, the
text, and the trailer (error detection and correction bits).
Packing
-
The act of combining multiple service data units (SDU) from a
higher layer into a single medium access control protocol data
unit MPDU.
Physical Layer
PHY
Provides for the transmission of data through a communications
channel by defining the electrical, mechanical, and procedural
specifications.
Physical slot
PS
A unit of time, dependent on the physical layer specification, for
allocating bandwidth. PS is designated by 1 OFDM symbol.
PIR
-
Maximum Sustained Traffic Rate (see QoS)