CDMA/FDD Standard

CDMA/FDD Standard

Interim Standard 95 (IS-95): The IS-95 standard, also popularly known as CDMAOne,
uses 64 orthogonally coded users and codewords are transmitted simultaneously
on each of 1.25 MHz channels. Certain services that have been standardized as a
part of IS-95 standard are: short messaging service, slotted paging, over-the-air
activation (meaning the mobile can be activated by the service provider without
any third party intervention), enhanced mobile station identities etc.

 2.5G Mobile Networks

In an eort to retrot the 2G standards for compatibility with increased throughput
rates to support modern Internet application, the new data centric standards were
developed to be overlaid on 2G standards and this is known as 2.5G standard.
Here, the main upgradation techniques are:
 supporting higher data rate transmission for web browsing

 supporting e-mail trac
 enabling location-based mobile service
2.5G networks also brought into the market some popular application, a few of
which are: Wireless Application Protocol (WAP), General Packet Radio Service
(GPRS), High Speed Circuit Switched Dada (HSCSD), Enhanced Data rates for
GSM Evolution (EDGE) etc.