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In a perfect world, the terminating sensor would present a perfect load, and then by reorganizing
the above two definitions with incident and output power equal, we would have,
Because power sensors are always imperfect loads, additional analysis and sometimes correction
is required.
Figure 4 shows a signal flow diagram of two one-port devices connected. The left-hand port is
the "output", or "generator" port and is designated on the diagram using the subscript, "g". The
right-hand port is the "input", or "load" port and is designated using the subscript "l". It's clear
from the diagram that port reflections dominated by the Gamma vectors generally cause the
power that the generator port would output into an ideal load, ��
, incident on the load. We must consider the combination of reflections, or "port match" to
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come up with a general understanding of calibration transfer.
Start with the signal flow diagram. In this case, a Generator "g" is represented by an ideal source
"s", and its port reflection, and the sensor is termed the load, "l".
b
s
2818A-900 Revision AB
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Figure 4 - Signal Flow Diagram
RF Power Transfer Standard
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, to not be equal to the power
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−
P
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r
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