August 19th, 2016 by
Deterministic digital signal processing is one of the most popular forms of signal processing. Due to advances in software and computer technology for real-time programs or applications, there has been rapid development in the digital signal processing arena. Digital processing refers to the procedures that are used to show information in measured data. Essentially, the procedures depend on different mathematical based transformations that are implemented through the use of digital techniques. Due to the wide software availability when it comes to carrying out digital signal processing, it now pervades different areas of engineering, science and medicine among others. The ease of carrying out this processing sometimes leads to leveraging the wrong tools. There are also cases when results are interpreted incorrectly due to lack of understanding or appreciation of the limitations or assumptions of the employed methods.
Deterministic digital signal processing can be classified into three categories.
1. Period signals
These are defined as signals with waveform that repeat at exact regular time intervals. There is an abrupt change with this signal every second. In reality, there is hardly a perfect period signal. However, it can be obtained by measuring certain physical phenomenon like accelerometer output measurement when the device is placed close to a cylinder head of a car engine that is in constant speed. In that case, it might be more useful if the signal is considered as comprising simpler components.
2. Almost-period signal
Almost-period signal is in some cases known as quasi-periodic signal. That is, the signal looks like a period signal but it’s not when observed closely. An example of this signal is the acoustic signal that is created when a wine glass that is slightly asymmetric is tapped.
3. Transient signal
Transient means some limitation in the time of this signal. This signal is analyzed using Fourier integral. It has a frequency characteristic that varies from Fourier series. A practical example of this signal in vibration engineering is impact testing to estimate frequency response function of a structure.