20
Terminal RF and Baseband Design Challenges
20.1 Introduction
This chapter presents an overview of the Universal Mobile Telecommunication Services (UMTS) Terrestrial Radio Access Network (UTRAN) design challenges imposed by some 3rd Generation Partnership Project (3GPP) test cases, with a focus on radio-frequency (RF), talk-time improvements due to Continuous Packet Connectivity (CPC), and also partly covering the impacts on baseband (BB). Section 20.2 presents design challenges in the WCDMA transmitter chain. Section 20.3 similarly covers the receive path, talk-time savings are presented in Section 20.4 and Section 20.5 opens a discussion related to the design of next-generation ‘world-wide’ phones which have to support multiple frequency bands as well as radio systems other than WCDMA.
3GPP has produced new Releases recently at roughly two-year intervals (Release 5 first version March 2002, Release 6 first version December 2004 and Release 7 December 2007) accelerating with Release 8 (December 2008) and Release 9 (early 2010), and thus is delivering plenty of new features for designers to cope with when designing new Release capable devices. The design cycle of a mobile phone takes on average 2 to 3 years, from first system requirements documents, to Integrated Circuit (IC) tape-outs, integration of hardware and software, hardware re-spins, to conformance tests, to handset available off-the-shelf. As the hardware ...
