Examples of Air‐Interface Standards: GSM, IS‐95, WiFi
Kuok-Shoong Daniel Wong · 2011
This chapter examines physical layer and link layer aspects of the most popular commercial wireless personal communications systems. It begins with global system for mobile communications (GSM), the predominant TDMA-based second-generation system. GSM uses Gaussian minimum shift keying (GMSK) for its modulation scheme. The chapter then discusses the second-generation IS-95 CDMA system. It must be noted that IS-95 CDMA systems reuse frequencies in every cell, nor are the signals separated in time. Thus, the proper use of codes for separating the various signals is essential for the operation of a CDMA system. The chapter also surveys IEEE 802.11 standard. A fundamental building block in 802.11-based networks is the basic service set (BSS) concept. There are actually two kinds of BSSs: independent BSS (IBSS), also known as the ad hoc network of 802.11; and infrastructure BSS. Controlled Vocabulary Terms GSM; IEEE 802.11 Standards; minimum shift keying; Multiaccess communication; wireless personal area networks