S

SACCH - Slow Associated Control Channel
(transmits continuous measurements in parallel with operation of TCH or SDCCH; needed for handover decisions)

SAR - Specific Absorption Rate

SB - Synchronisation Burst; used for time synchronisation of the mobile

S-CDMA - Synchronous CDMA (see CDMA)

SCH - Synchronisation Channel
(downlink only frame synchronisation and identification of base station)

SCP - Switching/Service Control Point

SDCCH - Stand-alone Dedicated Control Channel; communications channel between the MS and the BTS. Used for signalling during call set-up before a TCH is allocated



SDK:
a Software Development Kit for wireless application developers. 
SDLC
Synchronous Data Link Control

SDMA - Spatial Division Multiple Access
(a variation of TDMA and CDMA that potentially will be used in high-bandwidth, third-generation wireless products.)


Security Code:
a numeric code (password) used to prevent unauthorized or accidental alteration of data programmed into wireless phones. The security code can be used by the owner of a phone to change the lock code. 

SGSN - Serving GPRS Support Node


SIM - Subscriber Identity Module
A smart card containing the telephone number of the subscriber, encoded network identification details, the PIN and other user data such as the phone book. A user’s SIM card can be moved from phone to phone as it contains all the key information required to activate the phone

SoHo - Small Office/Home Office

Streaming:
An Internet derived expression for the one-way transmission of video and audio content

STK
SIM ToolKit: specified within the GSM standard, this allows operators to add additional functions to the phone menu in order to provide new services such as mobile banking or email


Smartphone:
a combination of mobile phone and personal digital assistant

SMR - Specialised Mobile Radio; the US term for private mobile radio (See PMR)

SMS - Short Message Service
(a text message service which enables users to send short messages (160 characters) to other users. A very popular service, particularly amongst young people, with 400 billion SMS messages sent worldwide in 2002)

SMSC - SMS Centre-the network entity which switches SMS traffic

SMSCB - SMS Cell Broadcast

SMS-MO - SMS Mobile Originated

SMS-MT - SMS Mobile Terminated

SMS-PP - SMS Point to Point


SNR - signal to noise ratio
SP - Service Provider

SQAM - Staggered Quadrature Amplitude Modulation

SQPSK - Staggered Quadrature Phase Shift Keying

SRAM - Syncronous Random Access Memory

SS - Supplementary Service Support; handles special services

SS7 - Signalling System Number 7 (See CCS7)

SSP - Service Switching Point


Standby time:
The length of time a battery can power a mobile phone when it is switched on but not making or receiving calls

STM - Synchronous Transfer Mode

Symbian:
A company created by Psion, Nokia, Ericsson and Motorola in 1998 with the aim of developing and standardising an operating system which enable mobile phones from different manufacturers to exchange information
The operating system is known as EPOC. Matsushita has subsequently joined Symbian
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