ANALOG-TO-DIGITAL CONVERSION The Pulse Code Modulation (PCM) Technique By Dr. Ernest Simo 1.0 Nyquist Sampling Analog to Digital Conversion An Analog to Digital Converter transforms an analog signal to a digital signal. This process has three steps: Sampling: makes the signal discrete in time. Quantization: makes the signal discrete in amplitude. Source Encoding: represents the quantized levels as a sequence of digital bits. Sampling does not introduce distortion if the analog input signal is bandlimited and the sample rate is sufficiently high. Quantization does introduce distortion, and in many cases, contributes as a limiting factor in the quality of the overall system. CODE: AN INTRODUCTION By Dr. Ernest Simo © 1999 DR. ERNEST SIMO - SPACE2000