User's Manual

Null An RF signal component with a smaller amplitude than the rest of
the RF signal in multipath interference. Nulls are caused by
subtractive combination as a result of multipath fading.
Null Depth The ratio in dB between the strongest OFDM carrier and the
weakest carrier in multipath interference. A null depth of zero
indicates that there is no multipath reception.
11.12 O
Obstructed Line
of Sight
( OLOS)
Urban
OLOS is a partially blocked elliptical cylinder, whose diameter
depends on frequency and distance that can be drawn between
two transmitting devices. An object is infringing or cutting into the
cylinder. OLOS can occur in various degrees of severity. Large
amounts of reflection, refraction and/or diffraction occur on a
direct ray between the transmitter and receiver.
OFDM Orthogonal Frequency Division Multiplexing. A method of splitting
the data stream into a number of channels, each transmitted
simultaneously on a different frequency. Allows greater range with
less power, higher data rates, less distortion and greater immunity
to interference.
OFDM Station
Type
Configuration setting where the base and remote are defined. The
APs are base stations. The CPEs are remote stations.
OI D nodes Object Identifier Nodes. These are the individual nodes in an MI B.
See SNMP and MIB.
Orthogonal An adjective that refers to the way the many carrier waves in a
OFDM system affect each other. The carriers are spaced in such a
way that the center frequency of each signal lies in the null spot of
its neighbors. This minimizes interference.
Overhead Anything that reduces the payload capacity of a system is
overhead, even if it is useful. Link monitor data determines
transmission statistics, but it reduces the message-carrying
capacity of the system and is considered overhead.
11.13 P
Packet Loss Occurs when one or more packets of data traveling across a
computer network fail to reach their destination. Packet loss is
distinguished as one of the three main error types encountered in
digital communications; the other two being bit error and spurious
packets caused due to noise.
Path Loss The total loss from one end of the path to the other. This includes
propagation losses, cable losses, and any other losses that affect
the system performance.
LibraPlus 5860 User Guide Appendix B: Definitions: O Page 85 of 95