
3-54
ES User’s Guide
Making Measurements
Measuring S11 Reflection Port 1 using a One-Port Calibration
View and Interpret the S11 Measurement
Results
1. To view the entire measurement trace on the display, press
.
2. To interpret the reflection measurement, refer to
“Example of an S11 Measurement Display,”
if you are making this measurement on your instrument.
a. The values shown on the horizontal axis are the frequencies in
MHz. The values shown on the vertical axis are the power ratios
in decibels (dB) of the reflected signal divided by the incident
power. To display the result in logarithmic magnitude format
(designated by Log Mag at the top of the measurement screen),
the analyzer computes the measurement trace using the following
formula:
where P
refl
= the power of the signal reflected from the device and
where P
inc
= the incident power.
b. A level of 0 dB indicates that all of the power applied to the DUT is
reflected back, and that none of it passes through the DUT or is
absorbed by the DUT.
c. Values less than 0 dB indicate that power is either absorbed or
transmitted by the DUT. Although not commonly seen, values
greater than 0 dB can occur under certain circumstances such as
when the measurement needs to be enhanced by calibration, or
when the device is active (an amplifier for instance) and perhaps
oscillating.
SCALE
Autoscale
Reflection dB
(
)
10 log
P
refl
P
inc
----------
=
Summary of Contents for HP 8712ES
Page 8: ...viii ES User s Guide ...
Page 17: ...ES User s Guide 1 1 1 Installing the Analyzer ...
Page 34: ...1 18 ES User s Guide Installing the Analyzer Preventive Maintenance ...
Page 35: ...ES User s Guide 2 1 2 Getting Started ...
Page 52: ...2 18 ES User s Guide Getting Started Performing the Operator s Check ...
Page 53: ...ES User s Guide 3 1 3 Making Measurements ...
Page 135: ...ES User s Guide 4 1 4 Using Instrument Functions ...
Page 159: ...ES User s Guide 4 25 Using Instrument Functions Using Markers Figure 4 15 Delta Marker Mode ...
Page 165: ...ES User s Guide 4 31 Using Instrument Functions Using Limit Testing Figure 4 16 Limit Lines ...
Page 224: ...4 90 ES User s Guide Using Instrument Functions Using an External VGA Monitor ...
Page 225: ...ES User s Guide 5 1 5 Optimizing Measurements ...
Page 246: ...5 22 ES User s Guide Optimizing Measurements Measuring Devices with Long Electrical Delay ...
Page 247: ...ES User s Guide 6 1 6 Calibrating for Increased Measurement Accuracy ...
Page 281: ...ES User s Guide 7 1 7 Front Rear Panel ...
Page 306: ...7 26 ES User s Guide Front Rear Panel Line Module ...
Page 307: ...ES User s Guide 8 1 8 Hardkey Softkey Reference ...
Page 410: ...8 104 ES User s Guide Hardkey Softkey Reference Z ...
Page 411: ...ES User s Guide 9 1 9 Specifications ...
Page 469: ...ES User s Guide 10 1 10 Safety and Regulatory Information ...
Page 475: ...ES User s Guide 10 7 Safety and Regulatory Information Regulatory Information ...
Page 476: ...10 8 ES User s Guide Safety and Regulatory Information Regulatory Information ...
Page 477: ...ES User s Guide 11 1 11 Factory Preset State and Memory Allocation ...