Autocoh - Analog Devices VISUALDSP++ 3.5 Manual

DSP Run-Time Library Reference

autocoh

autocoherence
Synopsis
#include <stats.h>
void autocohf(a,n,m,c)
const float a[];
int n;
int m;
float c[];
void autocoh_fr16 (a,n,m,c)
const fract16 a[];
int n;
int m;
fract16 c[];
Description
This function computes the autocoherence of the input elements con-
tained within input vector
Algorithm
− −
n k 1
1
∑
=
c * ( ( a
k
n
=
j 0
where k={0,1,...,m-1} and
Domain
38
-3.4 x 10 to +3.4 x 10
-1.0 to 1.0
4-28
, and stores the result to output vector
a
− −
a ) * ( a a ))
+
j j k
is the mean value of input vector
a
38
VisualDSP++ 3.5 C/C++ Compiler and Library Manual
/* Input vector a
/* Input samples
/* Lag count
/* Output vector c
/* Input vector a
/* Input samples
/* Lag count
/* Output vector c
for
autocohf( )
for
autocoh_fr16( )
*/
*/
*/
*/
*/
*/
*/
*/
.
c
.
a
for ADSP-219x DSPs