Teledyne LeCroy ArbStudio - Manual (Page 96)

ArbStudio
88 922244-00 Rev A
Two compression algorithms are used for a Segment memory usage
optimization. The algorithm used depends on the linear or non-linear
behavior of the selected function (Type).
The maximum compression factor corresponds to equally separated
samples in both cases, with a separation time equal to the minimum time
resolution allowed. Intermediate compression factors can be set by
controlling the amplitude factor (Decimation Factor).

Decimation Factor - Physically represents a percent value of the
signal maximum amplitude and is used by the compression
algorithm differently depending on the linear or nonlinear behavior
of the function selected (Type).

Linear Compression - The compression algorithm is linear for a
signal characterized by a linear time variation of the signal amplitude
(Increase Ramp, Decrease Ramp).
The compressed signal samples are equally spaced and the
separation between two successive samples is given by one of the
following conditions (the strictest one applies):

The maximum time separation between two successive
samples must be equal to the minimum resolution.

The minimum amplitude gap between two successive
samples is given by the percent of the maximum signal
amplitude, set by Decimation Factor. For example, a signal
with a maximum voltage of 10V and a Decimation Factor of
10%, the minimum voltage gap is 1 V.

Non-Linear Compression - The compression algorithm for non-linear
functions (Triangle, Rectangle, Sawtooth, Sine and Cosine) is similar
to the previous one, but the compressed signal samples are equally
separated only if the Decimation Factor is such that the former
condition is satisfied.
By using a suitable Decimation Factor the algorithm allows compressing the
modulating signal using a cluster of samples directly proportional to the
amplitude variation in the time unit.
Therefore, the compression algorithm for non-linear signals takes into
account the relative time variation of the signal amplitude.