An overview of digital telephony standards

The purpose of this paper is to provide a general overview of digital telephony standards as an introduction to the discussions on the design of digital cellular handsets. The paper focuses on the four digital cellular standards: GSM, TDMA (IS-54/IS-136), CDMA (IS-95), and PDC, and also mentions the digital cordless standards: DECT and Personal Handy-phone service (PHS) in passing. The paper also briefly reviews some of the general trends in handset technology.