CODEL SmartCem V-CEM5100

To Next Page

To Previous Page

Technical Manual Page 4 CODEL

OPS.109

Issue : B

Rev. : 1

Date : 23/10/13

Doc. i/d : 0109/6

Ref. : 090028

Using the correlation function R

() to operate on these two signals the following correlogram is obtained.

NOTE: with  = 0 (i.e. no delay on signal A(t)) then R

() = 0, and when A(t) has been delayed by six time-

intervals R

() is a maximum. The six time-intervals is the delay between the two signals.

Both signals are sampled and digitised at fixed time delay intervals. The correlation function of R

() is then

computed for a fixed number of time delay intervals to derive the correlogram. For example, if the set of data

above where each signal a(t) and b(t) each comprise a square pulse resulting in a triangular shaped

correlogram, just twelve time delay intervals are shown. The instrument always computes the correlation

function for 256 time delays intervals. The time delay interval used can be selected and is defined as the DATA

RATE. This is, in effect, the resolution of the time delay measurement. It is normally set to 1msec.

Now consider two actual signals from the transducers as shown below :

Using the correlation function R

() to operate on the above two signals a typical correlogram as shown below

is obtained.

CODEL SmartCem V-CEM5100 - Page 12