VX3400
79
GPS
G
lobal
P
ositioning
S
ystem is a system of
satellites, computers, and receivers able
to determine the latitude and longitude
of a specific receiver on Earth. Position
is calculated using time and distance.
IS 2000
Type of digital signaling. It's the second
generation of CDMA digital cellular, an
extension of IS-95. Differences between
signaling types have to do with pilot
signal and links to provide more traffic
channels, and control protocols.
NAM
N
umber
A
ssignment
M
odule is how the
phone stores the phone number and its
electronic serial number. A multiple
NAM phone can register with multiple
service providers and be set to
automatically switch between
programmed phone numbers for service
provider areas.
SID
S
ystem
Id
entification is a number
transmitted by base stations to identify a
wireless system which conforms to a
TIA cellular or PCS standard.
SID is used by mobile phones to
recognize when they are in their home
system and can be used for billing
purposes as a unique identification of
the serving system.
SMS
S
hort
M
essage
S
ervice is a service
available on most digital mobile phones
to send messages between phones or
other devices. Messages are routed a
Short Message Service Center (SMSC),
which attempts to send the message
and, if unsuccessful, possibly retry at a
later time. Message delays or message
loss is possible, especially when
sending between networks. Users can
request delivery confirmation reports.
TTY
T
ele
ty
pewriter. An electromechanical
typewriter that either transmits or
receives messages coded in electrical
signals. A phone with TTY support is
able to translate typed characters to
voice or translate voice into characters
to display on the TTY.
VX3400-(E)_1.3.qxd 1/12/07 8:44 AM Page 79
