Digital Alias-free Signal Processing

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Introduction: Signal Digitizing and Digital Processing

The approach used to discuss digital processing of signals in this book is special. As the title of the book suggests, the central issue concerns the performance of signal digitizing and processing in a way that provides for the elimination of negative effects due to aliasing. The term ‘digital alias-free signal processing’ is introduced and actually covers a wide subject area. As this term also raises some questions it needs to be explained.

1.1 Subject Matter

Signals originating as continuous-time variables, usually considered as analog signals, might be and often are processed directly using analog electronics. However, prior to processing, these signals could also be converted into their digital counterparts. Using analog-to-digital conversions for digitizing the signals prior to processing has many well-known advantages and is usually preferable. When the signals are digitized, the obtained digital signals are processed according to the concepts of digital signal processing (DSP) technology. Such an approach is becoming increasingly more popular as digital computer applications spread out into new fields and there is growing dependence on them. It is helpful that basically the same principles and techniques are used in both areas of signal processing and computing. However, signals can still be treated by analog signal processing techniques whenever application of digital techniques is either impossible or technically ...