Signals and Systems BY DR MANAL K OUDAH

Signals and Systems BY DR. MANAL K. OUDAH Coorelation Department of Electromechanical Engineering Department, University of Technology, Baghdad, Iraq

coorelation Correlation of Continuous Signals Correlation is a tool for analysing whether processes considered random a priori are in fact related. In signal processing, cross-correlation Rfg is used to assess how similar two different signals f (t) and g(t) are. Rfg is found by multiplying one signal, f (t) say, with time-shifted values of the other g(t), then summing up the products. signal f (t) would have a higher cross-correlation with parts of g(t)

coorelation Correlation of Continuous Signals Correlation: the general form of the correlation function between two signal f 1(t)& f 2(t). Auto Correlation: it is the correlation of a function with itself. It provides a measure of the degree to which a future value of the function can be predicted. Cross Correlation: the Cross Correlation function or measures the similarity between two signals f 1(t)&f 2(t).

coorelation Benfit of Correlation The process of correlation is useful in comparing two deterministic signals and it provides a measure of similarity between the first signal and a time delayed version of the second signal Correlation techniques are widely used in signal processing with many applications in telecommunications, radar, medical electronics, physics, astronomy, geophysics etc. . . Correlation has many useful properties, giving for example the ability to: Detect a wanted signal in the presence of noise or other unwanted signals.

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coorelation Basic properties of auto-correlation 1. Symmetry: The auto-correlation function is an even function of. Rff (t ) = Rff (-t ): 2. For a non-zero signal, Rff (0) > 0. 3. The value at ( t) = 0 is largest Rff (0) = E for energy signal