Anritsu 37 C Series, Operation Manual

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The most difficult types of measurements are those that exercise the
full dynamic range of the 37XXXC, such as filters (Figure 8-). Filter
measurements are examples of where one must observe both
low-insertion loss (in the passband) and high attenuation (in the stop
band).
There are two techniques that you can use to optimize the sig-
nal-to-noise ratio. They are (1) maximizing the RF signal level and (2)
using signal enhancement.
To maximize the RF signal level, use the default settings of the
37XXXC.
The 37XXXC provides two enhancements for improving the sig-
nal-to-noise ratio: IF bandwidth reduction and averaging.
Reducing the IF bandwidth is a primary method for enhancing accu-
racy. The 37XXXC has a choice of four bandwidths available from the
front panel: Maximum (10 kHz), Normal (1 kHz), Reduced (100 Hz),
and Minimum (10 Hz). The noise level should decrease by a factor
equal to the square root of the IF bandwidth. Using IF Bandwidth re-
duction makes for faster measurements than with the use of an equiv-
alent amount of averaging.
37XXXC OM 8-15
MEASUREMENTS LOW LEVEL AND GAIN
TECHNIQUES TO MAXIMIZE THE S/N
RATIO
Maximize RF Signal Level
Signal Enhancement
MAXIMIZE RF SIGNAL LEVEL
Maximum Dynamic Range
Optimum Linearity
ENHANCEMENTS
IF Bandwidth Reduction
Averaging
IF BANDWIDTH REDUCTION
Four Bandwidths Available
Noise is Decreased
Faster Than Averaging