JPL's Wireless Communication Reference Website

Chapter: Network Concepts and Standards
Section: Data Systems, CDPD

CDPD Architecture

Contributed by Yi-Bing Lin

CDPD can be overlaid on existing analog cellular systems (specifically, AMPS) and share their infrastructure equipments on a non-interfering basis. Basically, CDPD transmits packet data over idle cellular channels, and mechanisms called channel sniffing and channel hopping are used to autonomously switch the CDPD stream to another channel when the current channel is about to be assigned for voice usage. CDPD does not communicate with the underlined cellular network. However, CDPD takes advantage of its knowledge of the channel assignment algorithm of the cellular cell, and predicts the channels available for CDPD use. Three network elements are considered in CDPD: CDPD handover is mobile controlled. CDPD user mobility is supported by Mobile Network Location Protocol .

Organization of this Topic


  1. Lin, Y.-B. Cellular Digital Packet Data: A Tutorial. Submitted to International Journal of Wireless Information Networks
  2. CDPD Forum, Inc. Cellular Digital Packet Data System Specification: Release 1.1. January, 1995.
  3. Quick, R.F., Jr. An Overview of the Cellular Digital Packet Data (CDPD) System. IEEE PIMRC, 338-343, 1993.
  4. Pawlowski, C., and McConnell, P. CDPD Air Interface Basics. Telephony, 49-62, December 5, 1994.

JPL's Wireless Communication Reference Website Yi-Bing Lin (Author) and Jean-Paul M.G. Linnartz (Ed.), 1996.