What is IS-95: CDMA?

IS-95 is a standard for CDMA (Code Division Multiple Access) Digital Cellular.

Mobile Frequency Range	Rx: 869-894; Tx: 824-849
Multiple Access Method	CDMA/FDM
Duplex Method	FDD
Number of Channels	20 (798 users per channel)
Channel Spacing	1250kHz
Modulation	QPSK/OQPSK
Channel Bit Rate	1.2288Mb

How CDMA Works

In a CDMA system, your encoded voice is digitized and divided into packets. These packets are tagged with "codes." The packets then mix with all of the other packets of traffic in the local CDMA network as they are routed towards their destination. The receiving system only accepts the packets with the codes destined for it.

CDMA vs. TDMA

The CDMA technology used in IS-95 is in technical competition with the TDMA (Time Division Multiple Access) technology used in GSM.

IS-95 by Any Other Name

IS-95 is also known as TIA-EIA-95.

The original IS-95 CDMA specification is now referred to as cdmaOne.

Newer CDMA Standards

Newer CDMA standards include cdma2000, CDMA 1X EV, CDMA 1XEV-DO, CDMA MC 3X, WCDMA and TD-SCDMA.

CDMA-2000 1xRTT is a recent standard for data networking over CDMA-2000 networks.

CDMA Network Operators

ALLTEL, Verizon Wireless, US Cellular, and Qwest communications operate CDMA networks within the United States. Worldwide, there are over 60 million users of IS-95 and other CDMA networks.

Additional Reading on CDMA

For more information on CDMA, visit the CDMA Development Group.

Books on IS95: CDMA

CDMA IS-95 for Cellular and PCS	This practical, readable guide makes CDMA IS-95 (Code Division Multiple Access) accessible to working telecommunications engineers and managers. CDMA is the most advanced of the three digital cellular standards being used worldwide, and is fast becoming a key component of new PCS networks as well. Readers will find everything they need to know about CDMA for wireless implementations, a concise listing of all CDMA radio and network specifications; a directory of major CDMA equipment suppliers; and more.
IS-95 CDMA and cdma 2000: Cellular/PCS Systems Implementation	Of all wireless technologies for personal communications. Code Division Multiple Access (CDMA) offers the best combination of good signal quality, high security, low power consumption, and excellent system reliability."--BOOK JACKET. "In this book, Vijay K. Garg, an experienced telecommunications authority, will teach you how to maximize the power of CDMA, migrate existing systems to the newest standards, and prepare for a smooth transition to features yet to come. IS-95 CDMA and cdma2000: Cellular/PCS Systems Implementation covers all aspects of up-to-date CDMA implementation and operation.
Spread Spectrum CDMA: IS-95 and IS-2000 for RF Communications	In the past 7 years CDMA (Code Division Multiplexed Access) has grown from a small experiment to the technology that is going to replace all existing wireless methods in North America and around the world, replacing even GSM, which up to now has been deeply entrenched in Europe and elsewhere. Though many books cover it conceptually, there are few that deal in the application of CDMA to the day-to-day functioning of the wireless network. This book is focused on the workplace needs of RF managers and engineers. Mathematically difficult material has been culled from the body of the book and placed in carefully organized appendices, so readers have access to derivations but don't have to wade through them to find the solutions they're looking for. And unlike any existing CDMA book, this details the similarities and differences between the 2G IS-95 and 3G IS-2000 standards, focusing on the many issues that changeover is going face.
CDMA Systems Engineering Handbook	Provides an explanation of code-division multiple access technology and the technical details and engineering principles behind the new IS-95 digital cellular system standard. Covers mobile radio propagation considerations, basic cellular systems engineering, Walsh functions and CRC codes, pseudonoise sequences, diversity techniques and rake processing, CDMA cellular system design, and CDMA optimization issues. The book is based on materials used for extensive technical courses conducted by the first author in Korea and the US.