Specifications

11
Get Results, Mot Just Data, Using High-Level Signal
and Trace Processing Tools
The built-in, high-level functions of the 8568B provide signal and trace
processing tools that increase measurement capability and speed the
development of measurement programs. Signal processing tools such as
PWRBW (finds the power bandwidth of a signal) and PEAKS (identifies
nil responses on the display) allow data processing to be performed by the
analyzer without an external computer. Trace processing functions such as
RMS (finds the RMS value of a trace) and MPY (multiplies two traces, point
by point) eliminate long delays for transferring data to a computer, since
they are performed internally. Some functions process and store data in
the analyzer’s RAM. Others allow more than one active trace to be displayed
simultaneously.
By combining these functions, application-specific routines can be defined,
usually from a controller, and executed as front panel softkeys or as
computer-controlled routines. The examples below illustrate some application
areas which can be addressed.
Surveillance
Signals can be monitored in any
user-specified band using the built-in
PEAKS routine. PEAKS identifies the
number of signal responses above a
threshold and records measurement
data on each signal identified, Using
PEAKS with other functions, trace
information and measurement data
can be simultaneously displayed.
Measurement data can also be
transferred to a system controller
printer, or plotter.
Mobile radio
The power bandwidth of many
types of signals can be calculated
internally with the PWRBW function.
For example, the modulation
bandwidth of an FM transmitter
can be measured for a user-specified
“percent of power” value. PWRBW
is also useful for voice modulated
measurements in AM, SSB, and
FM systems.
Amplitude modulation analysis
Previously, signals with very low
modulation rates and low modulation
indices could not be measured
because of resolution limitations
in the frequency domain. Now, with
the FFT function, the modulation
frequencies and distortion can be
easily measured. FFT also enables
accurate measurement of AM in the
presence of incidental phase angle
modulation.
PEAKS identifies all responses on the display FFT performs a fast fourier transform PWRBW returns the power bandwidth of a signal