Fundamental Concepts and Techniques: Sampling and Quantizing
Our main purpose in this book is to study the basic techniques required to accurately simulate communication systems using digital computers. In most communications applications, waveforms are generated and processed through the system under study. The computer, of course, can only process numbers representing samples of the waveforms of interest. In addition, since the computer has finite word length, the sample values have finite precision. In other words, the sample values are quantized. Thus, sampling and quantizing are underlying operations in all digital simulations, and each of these operations give rise to errors in the simulation results. The complete elimination of these error sources is not possible and tradeoffs are often required. We will see that the best we can do is to minimize the effects of sampling and quantizing on simulation accuracy. It is worth noting that many physical systems make use of digital signal-processing (DSP) techniques and also suffer from the effects of sampling and quantizing errors.