Let denote crosscorrelation. Then the crosscorrelation of two functions and of a real
variable is defined by

(1) 
where denotes Convolution and is the Complex Conjugate of . The
Convolution is defined by

(2) 
therefore

(3) 
Let
, so and
The crosscorrelation satisfies the identity

(5) 
If or is Even, then

(6) 
where denotes Convolution.
See also Autocorrelation, Convolution, CrossCorrelation Theorem
© 19969 Eric W. Weisstein
19990525