3GPP - third generation partnership project

3GPP2 - third generation partnership project 2

AAL 5 - ATM adaptation layer type 5

AAL2 - ATM adaptation layer type 2

AC - authentication center (also AuC) or administration center

ACCLOC - authentication center

ACELP - algebraic code excitation linear prediction

ACH - access channel

ACI - adjacent channel interference

ACK - (1) acknowledge (2) acknowledgment

ACLR - adjacent channel leakage ratio, caused by the transmitter nonidealities, the effect of receiver filtering is not included

ACM - (1) accumulated call meter (2) address complete message

ACSE - Association Control service element

ACT - analysis control terminal

ACTS - advance communication technologies and systems, EU research projects framework

ADPCM - adaptive differential pulse code modulation

AICH - acquisition indication channel

AM - (1) amplitude modulation; (2) ante meridian, before noon.

AMD - acknowledged mode data

AMPS - advanced Mobile Phone System

AMR - adaptive multirate (speech codec)

ANSI - American National Standards Institute

ARIB - Association of Radio Industries and Businesses (Japan)

ARQ - (1) Automatic Request to retransmit (2) Automatic Repeat Request

ASC - access service class

ASN. 1 - abstract syntax notation one

AT - (1) access tandem (2) prefix for dialing using a modem

ATM - asynchronous transfer mode

AuC - authentication center (data base); associated with HLR

AWGN - additive white Gaussian noise

BB - baseband filter

BB SS7 - broadband signaling system #7

BBCCH - (1)broadcast channel (logical channel) (2) broadcast common control channel

BBCE - base band...