The P/Ar - HP 4935A Operating And Service Manual

Model 49'ISA
Operation
weighted measure of the total attenuation, phase distortion, and noise. The P/AR rating is derived by
comparing the P/AR of an ideal signal with the P/AR of the output signal of the system under test. The
reduction, gain ripples, nonlinearities such as compression and clipping, and other impairments. P/AR is
simpler to understand than envelope delay because it is only one number instead of a curve. Also P/AR can
be measured in loop-around mode with only one instrument, unlike envelope delay. If the P/AR signal were
the pea k-to-;rveragc ratio has a P/AK rating of 80.
particular case. However, since P/AR is a figure of merit for the channel, it can be used as a benchmark for
future reference. After other measurements are made and a channel is considered acceptable, the P/AR
rating can he recorded for future reference. In case of a suspected trouble on the channel, P/AR may be
measured first and he compared to the benchmark P/AR value. Deviations in excess of +4 P/AR units from
an initial P/AR value provides sufficient reason to suspect that some channel characteristic has changed
significantly.