AT&T next generation digital cellular base station technology

Abstract

Cellular telecommunications is growing at a rapid rate throughout the world since its introduction in the United States by AT&T in 1981. Current usage within the United States has reached the two millionth customer mark and is still expanding. Market forcasters expect cellular customer usage to grow to 78 to 20 million subscribers by mid-year 1993, which represents a penetration rate within the U.S. of approximately 10 percent. Simultaneous with this expanding demand for cellular service, the U.S. cellular standards organization TM (Telecommunications Industry Association)and the Cellular Telecommunications Industry Association (CTIA) is cooperating in the development of the next generation digital radio standards for technology deployment in the 1991 time frame. This next generation technology has the potential of increasing the number of customers within the currently assigned U.S. cellular spectrum by afactor of three to four. Based on the needs of cellular network providers for high capacity and more flexibility, AT&T has developed a next generation digital cellular base station. The three key technologies to the implementation of AT&T's new digital cellular base station system are the intelligent control complex, analog and digital radio units and base station facilities networking. The intelligent base station control complex has been designed to support the emerging U.S. 30 kHz TDMA standard at the user to radio network interface and programmable communications pro cessors at the switching center interface. Radio technology is exploited by taking advantage of state-of-the-art digital radio channel techniques including linear amplification and digital signal processing. Substantial physical size reduction is achieved through extensive use of surface mount technology. Vie system has been designed as a world class product with rhefkxibility to handle different radio standards and network transmission inter faces. The system is designed to collect information about the performance of the mobile network there by enhancing the operator's ability to diagnose troubles, to assess performance, and with the help of the mobile switching center, to take corrective action. This paper will examine AT&T's next generation digital cellular base stationfrom an architecture, technology and application perspective.