Glossary
of T
erms
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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 provide 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
wireless phone without lifting or holding
the handset - an important safety feature
for automobiles, tractors and most other
motorized vehicles.
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 battery charging 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 is
determined, in part, by the frequency of the
signal they receive. Wireless phones and
the base station 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 transmitted signal is just above noise
level across the available bandwidth.
Channel
- Communications signals transmit along
paths called channels.
Codec
- COmpression & DECompression.
Deactivation
- The process of rendering a wireless
phone inactive.
DTMF
- (Dual-tone Modulated Frequency) You send
DTMF signals when you enter numbers by
pressing the digit keys.
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