Introduction

Chapter 7 reviews the optional placements of the VQS functions relative to the mobile-switching center and the base-station controller, since placement impacts voice performance, applications, deployment cost, and data-detection algorithms. The first section of this chapter covers wireless-network architectures that provide comprehensive signal processing coverage for mobile-to-mobile call applications. The topic of economics and architectural trade-off associated with voice-enhancement systems is also addressed. The second part of the chapter presents an analysis of the techniques employed by a voice-quality system when coping with data communications without interfering or blocking its error-free transmission. The analysis includes descriptions of data-detection algorithms based on bit-pattern recognitions. The scope encompasses circuit-switched and high-speed circuit-switched data (CSD and HSCSD respectively) services. Finally, the third section describes tandem-free operation (TFO), its potential impact on speech transmission and data communication, and potential features and architectures.

The chapter characterizes two major themes and their joint interplay: (1) mobile-to-mobile network architectures with voice-quality enhancements, and (2) mobile data communications. It elaborates on various applications, technical challenges, and potential solutions. It is also intended to impart a sharper awareness of where technology is heading, and what constitutes winning features in the race to provide products that deliver superior voice quality in the wireless-communications arena.

The surge in data communications has spilled its fervor into wireless applications. Demand for higher-speed data access and the remarkable growth of internet applications have fueled the growth of this industry.