
Chapter 1 – Introduction
Multi-Tech Systems, Inc. CDMA Wireless AT Commands (PN S000294J)
10
Terminology and Acronyms
This is an alphabetical list of terms and acronyms used throughout this document and the CDMA cellular industry.
2G
Second Generation. All digital cellular systems developed to replace the first analog cellular systems. (GSM
and CDMA).
3G
Third Generation. Next generation digital cellular systems designed to have high-speed data access and
higher voice capacity (CDMA & CDMA2000).
AFLT
Advanced Forward Link Trilateration. A type of handset-based position location technology. GPS satellites
are not used to determine location. To determine location using AFLT, the phone takes measurements of
signals from nearby cellular base stations (towers) and reports the time/distance readings back to the
network, which are then used to triangulate an approximate location of the handset. In general, at least three
surrounding base stations are required to get an optimal position fix.
CBM
Cell Broadcast Message. An SMS message that is broadcast to all mobiles on the network.
CDMA
Code Division Multiple Access. CDMA is a spread spectrum, digital wireless modulation scheme for cellular
communications systems. It has approximately 3 times the voice capacity of GSM networks. See IS-95, IS-
95B, IS-2000.
cdmaONE
cdmaOne is a brand name, trademarked and reserved for the exclusive use of the CDMA Development
Group. cdmaOne describes a complete wireless system that incorporates the IS-95 CDMA air interface, the
ANSI-41 network standard for switch interconnection and many other standards that make up a complete
wireless system.
cdma2000
cdma2000 is a third generation (3G) wireless system. It contains a significant increase in voice capacity and
high-speed data rates. It is backward compatible with IS-95B and IS-95A.
DCE
Data Communications Equipment. This is the modem in the traditional serial communication paradigm of a
computer connected via two modems to another computer.
DTE
Data Terminal Equipment. This is the computer in the traditional serial communication paradigm of a
computer connected via two modems to another computer.
DTMF
Dual Tone Multi-Frequency: A pre-defined set of tones sent over the air when keys are pressed on the
keypad.
Handset (Path)
The audio path (microphone & speaker) that connects to a traditional hand held telephone receiver, usually
dual balanced electrical lines.
Headset (Path)
The audio path (microphone & speaker) that connects to an earpiece with a microphone, usually single
electrical lines.
IMSI
International Mobile Station IS. This is an international 15 digital phone number that uniquely identifies a
mobile. IMSI=MCC + MNC + MIN.
IOTA
Internet Over The Air.
IS-95
The first CDMA standard published by Qualcomm in 1993. It is a TIA standard for North American cellular
systems based on CDMA. It is widely deployed in North America and Asia.
IS-95A
A CDMA standard with improved voice quality. IS-95A defines what generally is known as cdmaOne, which
supports voice and 14.4 Kbps data rates. This is a worldwide standard.
IS-95B
This CDMA standard contains Medium Data Rate capabilities and bug fixes for system access failures. It is
considered a 2.5G system. It supports data rates up to 115 Kbps.
IS-2000
The first 3G CDMA standard based on IS-95B. It contains a significant increase in voice capacity and high-
speed data rates. It is backward compatible with IS-95B and IS-95A.
IS-707
TIA/EIA/IS-707 describes data services available on wideband spread spectrum systems. It is organized into
a series of related recommendations, some of which address functions common to all CDMA data services
and others that describe a specific data service.
IWF
:
Interworking Function. A process that acts as a gateway or interface between two or more communication
components. For example, an IWF is used to interface wireless CDMA networks and wire line PSTN or
packet-data networks.
LAPM:
Link Access Procedure for Modems. An error control protocol defined in the ITU-T recommendations V.42.
Like the MNP protocols, LAPM uses cyclic redundancy checking (CRC) and retransmission of corrupted
data (ARQ) to ensure data reliability.
MCC
Mobile Country Code. A pre-defined 30-digital number that represents a country in the IMSI.