Signal processing

The term signal processing all the processing steps are combined, which have the aim of extracting information from a signal ( received or measured ), or to prepare information for transmission of an information source to an information consumer. Thus, some important goals of signal processing are the extraction of information about processes, the reduction of data or the processing of signals.

Digital and analog signal processing

A distinction is made between digital and analog signal processing. The digital signal processing gains due to the following advantages more and more important:

• The results of digital signal processing are reproducible, component tolerances about by temperature changes or aging processes have less influence.
• The required processing steps can be performed with digital processing often easier to implement (eg by programming of microcontrollers ).
• Digital signal processing allows for the storage and easy processing (transmission to other systems, such as controls).
• Digital signal processing makes it possible to achieve a favorable signal -to-noise ratio S / N of the samples to be processed in dependence upon the selected or available bit width DSPs, FPGAs, microcontrollers, or signal processing software.

Disadvantages of digital signal processing:

• There are analog to digital converters ( ADCs ), and / or also digital to analog converter ( DAC ) with a certain sampling rate ( influence on the maximum scannable frequency; see Nyquist-Shannon sampling theorem ) and a degree of accuracy of measurement (Influence on the quantization error ) is necessary.
• In some cases, a double decomposition reaction is (analog → digital and later digitally → analog) necessary with the limitations or sources of error mentioned above.
• The implementation of some processing steps and also the execution of processing steps can be sometimes very time consuming. Time constraints during the execution of the processing steps can make approximations necessary.

Another distinctive possibility is the distinction between one-dimensional (eg, audio signals, seismic signals), two-dimensional ( such as images) and three-dimensional (eg, moving image, video ) signal processing.