ProSoft Technology RLXIB-IHA-A - Manual (Page 111)

RLXIB-IHA ♦ 802.11a Glossary of Terms
RadioLinx® 802.11a Industrial Hotspot User Manual
ProSoft Technology, Inc. Page 111 of 123
July 25, 2013
F
Firmware
Firmware is the embedded software code that that runs in the module to direct
module function (similar to the BIOS in a personal computer). This is
distinguished from the Setup/Diagnostic Application software that is installed on
the Configuration PC.
Frequency Hopping
A radio that rapidly changes its operating frequency several times per second
following a pre-determined sequence of frequencies. The transmitting and
receiving radios are programmed to follow the same frequency hopping
sequence.
Frequency Hopping Spread Spectrum
Changes or hops frequencies in pattern known to both sender and receiver.
FHSS is little influenced by radio stations, reflections, or other environmental
factors. However, it is much slower than DSSS.
Fresnel Zone
An elliptical area on either side of the straight line of sight that must also be clear
for a long-range wireless network to work.
Full-Duplex
A communications circuit or system designed to simultaneously transmit and
receive two different streams of data. Telephones are an example of a full-duplex
communication system. Both parties on a telephone conversation can talk and
listen at the same time. If both talk at the same time, their two signals are not
corrupted.
G
Gain
The amount by which an antenna concentrates signal strength in a wireless
network.
Gateway
In wireless terms, a gateway is an access point with additional software
capabilities such as providing NAT and DHCP.
H
Half-Duplex
A communications circuit or system designed to transmit and receive data, but
not both simultaneously. Citizens' Band (CB) or walkie-talkie radios are an
example of a half-duplex communication system. Either party to a radio
conversation may talk or listen; but both cannot talk at the same time without
corrupting each other's signal. If one operator is "talking", the other must be
"listening" to have successful communication.