A/D and D/A conversion for telecommunication

Emerging telecom systems such as ADSL and VDSL demand state-of-the-art high speed and high resolution analog-to-digital converters (ADCs) and digital-to-analog converters (DBCs). Moreover, cost and power consumption issues require the use of specific A/D and D/A architectures to achieve the wanted resolution at the required speed at minimum power. In the first part of this article we present an overview of the various ADC and DAC architectures used in Alcatel Telecom systems over the past 15 years, with an emphasis placed on the evolution of ADCs and DACs for today's asymmetrical-digital-subscriber-loop (ADSL) applications. We then discuss design considerations for high-speed and high resolution ADCs for future very-high-data-rate digital subscriber-line (VDSL) technology.