Nera WiLink-I 3000, Системное руководство

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WiLink-I Modular Base Station System Manual 215
PIU Power Interface Unit
POTS
Plain Old Telephone System. A basic analog telephone equipment.
PSU
Power Supply Unit
PPPoE Point-to-Point Protocol over Ethernet. PPPoE relies on two widely
accepted standards: PPP and Ethernet. PPPoE is a specification for
connecting the users on an Ethernet to the Internet through a
common broadband medium, such as a single DSL line, wireless
device or cable modem. All the users over the Ethernet share a
common connection, so the Ethernet principles supporting multiple
users in a LAN combines with the principles of PPP, which apply to
serial connections.
QAM
Quadrature Amplitude Modulation. A technique used in wireless
applications to double the available bandwidth by combining two
amplitude-modulated signals. The two combined signals differ in
phase by 90 degrees; this technique doubles the bandwidth by
combining the two signals at the source before transmission,
transmitting digital data at a rate of 4 bits per signal change.
QoS
Quality of Service. Measure of performance for a transmission
system that reflects its transmission quality and service availability.
QPSK
Quadrature Phase Shift Keying. A data transfer technique used in
coaxial cable networks that sends data using modulating signals.
Four different phases represent data, with each signal's information
determined by the signal before it. For example, if a phase stays the
same from one signal to the other, the information has not changed.
RF
Radio frequency. An AC signal of high enough frequency to be used
for wireless communications.
RFC Request For Comments. The name of the result and the process for
creating a standard on the Internet. New standards are proposed
and published on the Internet, as a Request For Comments. The
proposal is reviewed by the Internet Engineering Task Force.
RSSI
Received Signal Strength Indicator. A signal or circuit that indicates
the strength of the incoming (received) signal in a receiver.