The Application of Programmable DSPs in Mobile Communications

4

Programmable DSPs for 3G Base Station Modems

Dale Hocevar, Pierre Bertrand, Eric Biscondi, Alan Gatherer, Frank Honore, Armelle Laine, Simon Morris, Sriram Sundararajan and Tod Wolf

4.1 Introduction

Third generation (3G) cellular systems will be based on Code Division Multiple Access (CDMA) approaches and will provide significant data services as well as increased capacity for voice channels. This results in considerable computational requirements for 3G base stations. This chapter discusses an architecture that provides the needed computation together with significant flexibility. At the same time, this approach is one of the most cost effective known. Based upon a Texas Instruments TMS320C64x™ as the core DSP, the architecture utilizes three Flexible Coprocessors (FCPs): a Correlation Coprocessor for the CDMA portion, a Turbo Decoder Coprocessor for the data services, and a Viterbi Decoder Coprocessor for the voice services. The solution can be used for the two main flavors of 3G cellular as well as for second generation systems.

The explosive growth in wireless cellular systems is expected to continue. There will be 1 billion mobile users perhaps as early as 2003. 3G wireless systems will play a key role in this growth and roll-out of 3G should begin within 1 year. The key feature of 3G systems is the integration of significant amounts of data communication with voice communication, all at higher user capacities than previous systems. More recently, IP networking has become ...