Agilent Technologies 8719D, Руководство пользователя

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REFLECT
q
Reflection coefficient (I’ magnitude is optimally 1.0, but need not be
known.
q
Phase of must known and specified to within wavelength or
During computation of the error model, the root choice in the solution of a
quadratic equation is based on the reflection data. An error in
would show up as a error in the measured phase.
q
must be identical on both ports,
q
If the reflect is used to set the reference plane, the phase response must be
well-known and specified.
LINE/MATCH •I of the line establishes the reference impedance of the measurement
(i.e. = 0). The calibration impedance is to be the same as
of the line. If the is known but not the desired value (i.e., not equal to
50 the SYSTEMS selection under the options menu is used.
q
Insertion phase of the line must not be the same as the thru (zero length
or non-zero length). The difference between the thru and line must be
between and n x Measurement uncertainty will increase
significantly when the insertion phase nears 0 or an integer multiple of
•I Optimal line length is wavelength or of insertion phase relative to
the thru at the middle of the desired frequency span.
q
Usable bandwidth for a single pair is (frequency
frequency).
q
Multiple pairs assumed identical) can be used to extend the
bandwidth to the extent transmission lines are available.
q
Attenuation of the line need not be known.
q
Insertion phase must be known and within
wavelength or
LINE/MATCH
q
of the match establishes the reference impedance of the measurement.
q
must be identical on both ports
and calibration standards for
When calibrating a network analyzer, the actual calibration standards must have known
physical characteristics For the reflect standard, these characteristics include the offset in
electrical delay (seconds) and the loss (ohms/second of delay). The characteristic impedance,
reflection coefficient magnitude should optimally be 1.0, but need not be known since the same
reflection coefficient magnitude must be applied to both ports
The thru standard may be a zero-length or known length of transmission line. The value of
length must be converted to electrical delay, just like that done for the reflect standard. The
loss term must also be specified.
Application and Operation Concepts