Boonton 4500B Peak Power Meter - Manual (Page 18)

Boonton 4500B RF Peak Power Analyzer
General Information 1-2
1.2 Description
The Model 4500B RF Peak Power Analyzer is the latest generation of BOONTON RF Peak Power Meters
and Analyzers, including Models 4400, 4500, 4400A, 4500A and 4530. The Model 4500B, when
operated with 56000, 57000 and 58000 series power sensors, provides the most versatile power measuring
system available, with capability to make over 25 different power related measurements on captured
signals. The 4500B is available with a single or dual measurement channels.
All Model 4500B instruments provide two basic measurement modes - pulse power and modulated power
with an optional third mode - statistical power. Each mode is targeted towards a specific type of
measurement.
In the pulse power mode the instrument functions as an enhanced peak power analyzer. It can be
configured as a single or dual channel instrument. This mode provides the functionality of a random
repetitive sampling oscilloscope for viewing the RF envelope of signal frequencies up to 40 GHz. The RF
frequency range and detection bandwidth are sensor model dependent. Accuracy approaches that of
average power meters, but with the ability to capture power versus time data. With the requirement of an
internal or external trigger event it can automatically measure up to 15 characteristics of the RF envelope.
These are peak power, pulse power, average power, pulse width, risetime, falltime, overshoot, pulse period,
pulse repetition rate, duty cycle, top amplitude, bottom amplitude, offtime, edge delay and the delay
between two RF pulses or an RF pulse with an external trigger signal. In addition to the automatic
measurements, the instrument offers a powerful set of marker measurements which includes the ability to
make marker measurements at full accuracy, independent of vertical scale or offset. This is possible
because of the use of logarithmic amplifiers, and 14-bit analog to digital converters that provide
rangeless operation. In addition, the markers can be used to define regions of the waveform for analysis.
This analysis includes average power of a portion of the waveform, minimum power, and maximum power.
The modulated mode is designed for continuous true average power measurements of complex modulated
signals.
The optional statistical mode of the Model 4500B offers significant new features. This mode does not
require a trigger event to make measurements and is useful for signals that are noise-like or contain a burst
of noise-like modulation. In the continuous mode the RF signal is sampled 25 million times per second,
without discarding or losing any data. In the new gated mode, the samples are taken only within a time
window related to a trigger. All of this data is processed statistically to determine peak power, average
power, minimum power, peak to average power ratio, and dynamic range, while reporting the sampling
time and total samples captured.
The sampled data can be displayed as a CCDF, CDF or PDF statistical function. Power values can be
expressed in units of power, log power (dBm) or equivalent voltage across 50 ohms. Probability can be
expressed in percent or in log percent.