Boonton 4500B Peak Power Meter - Manual (Page 312)

Boonton 4500B RF Peak Power Analyzer
Application Notes 6-2
Figure 6-1.
Pulsed RF Signal
Figure 6-2.
Distorted Pulse Signal
Peak Power. The Model 4500B makes power measurements in a manner which
overcomes the limitations of the pulse power method and provides both peak power and
average power readings for all types of modulated carriers. The fast responding diode
sensors detect the RF signal to produce a wideband video signal which is sampled with a
narrow sampling gate The video sample levels are accurately converted to power on an
individual basis at up to a 1 MSa/sec rate. Since this power conversion is correlated to the
sensor pre-calibration table, these samples can be averaged to yield average power
without restriction to the diode square-law region. In addition, if the signal is repetitive,
the signal envelope can be reconstructed using an internal or external trigger. The
envelope can be analyzed to obtain waveshape parameters including, pulse width, duty
cycle, overshoot, risetime, falltime and droop. In addition to time domain measurements
and simple averaging, the Model 4500B has additional capabilities which allow it to
perform statistical, histogram type analyses on a complete set of continuously sampled
data points. Data can be viewed and characterized using CDF, 1-CDF and PDF
presentation formats. These analysis tools provide invaluable information about peak
power levels and their frequency of occurrence, and are especially useful for non-
repetitive signals such as HDTV and CDMA.