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In a number of countries throughout the world, a wireless service called the personal communication system (PCS) is available. In the broadest sense, PCS includes all forms of wireless communication that are interconnected with the public switched telephone network, including mobile telephone and aeronautical public correspondence systems, but the basic concept includes the following attributes: ubiquitous service to roving users, low subscriber terminal costs and service fees, and compact, lightweight, and unobtrusive personal portable units.

The first PCS to be implemented was the second-generation cordless telephony (CT-2) system, which entered service in the United Kingdom in 1991. The CT-2 system was designed at the outset to serve as a telepoint system. In telepoint systems, a user of a portable unit might originate telephone calls (but not receive them) by dialing a base station located within several hundred metres. The base unit was connected to the PSTN and operated as a public (pay) telephone, charging calls to the subscriber. Because of its limited coverage, the CT-2 system went out of service, giving way to the popular GSM digital cellular system (see mobile telephone).

Meanwhile, the European Conference on Posts and Telecommunications (CEPT) had begun work on another personal communication system, known as DECT (Digital Enhanced Cordless Telecommunications, formerly Digital European Cordless Telephone). The DECT system was designed initially to provide cordless telephone service for office environments, but its scope soon broadened to include campus-wide communications and telepoint services. By 1999 DECT had reached 50 percent of the European cordless market.

In Japan a PCS based loosely on the DECT concepts, the Personal Handy-Phone System (PHS), was introduced to the public in 1994. The PHS became popular throughout urban areas as an alternative to cellular systems. Supporting data traffic at 32 and 64 kilobits per second, it could perform as a high-speed wireless modem for access to the Internet.

In the United States in 1994–95 the Federal Communications Commission (FCC) sold a number of licenses in the 1.85–1.99-gigahertz region for use in PCS applications.