ABSTRACT
In UTRA FDD, the information is spread over approximately 5 MHz bandwidth with a chip rate of 3.84 Mchip/s. In UTRA TDD, two options are
specified. In one of them, the information is spread over approximately 5 MHz bandwidth with a chip rate of 3.84 MHz. In the other, the information is spread over approximately 1.6 MHz with a chip rate of 1.28 Mchip/s, and this alternative is mainly based on smart antenna technology. The first option is referred to as simply UTRA TDD, whereas the second option is known as time division-synchronous code division multiple access (TD-SCDMA) or 1.28 Mchip/s TDD. This chapter, for didactic purposes only, refers to the first option as UTRA TDD-3.84 and to the second as UTRA TDD-1.28. When no specific reference is made to any particular technology, the description in this chapter is applicable to the three technologies, namely, UTRA FDD, UTRA TDD-3.84, and UTRA TDD-1.28. Special attention, however, is given to UTRA FDD. >
The integration of user equipment, UTRA, and a CN results in a 3G system known as the universal mobile telecommunications system (UMTS). Although this chapter gives an overview of UMTS, it is mainly concerned with the UTRA component. For information on the other elements and 3G services the reader is referred to Chapter 7. The descriptions that follow are based on the technical specifications of References 8 through 18.
