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Glossary of Terms
EVRC
- (Enhanced Variable Rate Codec) EVRC is a new global
standard for compressing and decompressing voice
signals. EVRC uses a lower bit rate (the number of
bits sent per second) than existing CDMA vocoders,
while providing significant improvements in voice
quality. This technology enables your phone to pro-
vide superb voice quality while benefiting from the
ability to process more cellular voice calls using less
bandwidth than the voice codecs in CDMA networks
today.
Frequency
- A measure based on time, as one or more
waves per second, in an electrical or
lightwave information signal. A signal’s
frequency is stated in cycles-per-second or
Hertz (Hz).
Hands-Free
- A feature that permits a driver to use a wire-
less phone without lifting or holding the hand-
set - an important safety feature for automo-
biles, tractors and most other motorized vehi-
cles.
LCD
- (Liquid Crystal Display) Commonly used to refer to the
screen display on the wireless phone.
LED
- (Light Emitting Diode) Commonly used to refer to a small
light on the wireless phone or on the Desktop Charger.
The LED lights on the phone to indicate an incoming
call. The LED lights on the charger to indicate that
charging battery is taking place.
Prepend
- The addition of a prefix, such as an area code, to a
phone number.
RF
- Radio Frequency
Airtime
- Actual time spent talking on the wireless phone.
Most carriers bill customers based on how many
minutes of airtime they use each month.
Antenna
- A device for transmitting or receiving
signals. The size and shape of antennas are
determined, in part, by the frequency of the signal
they receive. Wireless phones and the base sta-
tion must have antennas.
Base Station
- The fixed radio transmitter/receiver that
maintains communications with mobile radio
telephones within a given area. (Typically
seen as cell or cell site.)
CDMA
- (Code Division Multiple Access) A spread-spectrum
approach to digital transmission. With CDMA, each
conversion is digitized and then tagged with a code.
The mobile phone deciphers only a particular code to
pick the right conversation off the air. The transmit-
ted signal is just above noise level across the avail-
able bandwidth.
Channel
- Communications signals transmit along paths
called channels.
Codec
- COmpression & DECompression.
Deactivation
- The process of rendering a wireless phone
inactive.
DTMF
- (Dual-tone Multi Frequency) You send DTMF signals
when you enter numbers by pressing the digit keys.
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