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ES User’s Guide 3-5
Making Measurements
Measuring Devices with Your Network Analyzer
Refer to Figure 3-3, “Block Diagram,” for the following discussion. The
network analyzer receiver has two signal detection modes:
• broadband detection mode
• narrowband detection mode
There are two internal broadband detectors: B* and R*. External
broadband detectors can also be used when connected to the X and Y
ports on the rear panel of the analyzer. When the network analyzer is in
the broadband detection mode, it measures the total power of all signals
present at these measurement ports, independent of signal frequency.
This enables the characterization of frequency translation devices such
as mixers, receivers, and tuners, where the RF input and output
frequencies are not the same.
Figure 3-3 labels the transmitted signal for
broadband detection input as B*, and the reference signal as R*.
When the network analyzer is in the narrowband detection mode, the
receiver is tuned to the source frequency. This technique provides greater
dynamic range by decreasing the receiver's bandwidth.
Figure 3-3 shows
receiver B as the narrowband detection input for the forward
transmitted signal and the reverse reflected signal. Receiver A acts as
the narrowband detection input for the reverse transmitted signal and
the forward reflected signal. Receiver R is shown as the narrowband
detection input for the reference signal.