Description Of The 86038A - Agilent Technologies 86038A User Manual

Description of the 86038A

Measurement Concepts

Description of the 86038A

The Agilent 86038A employs the modulation phase shift (MPS) method for
all of its measurements. A block diagram of the system is shown in
Figure 4. Light from the tunable laser is amplitude modulated by passing
the light through a balanced Lithium Niobate Mach-Zehnder modulator
that is driven by an RF source. The signal passes through the test device to
an optical receiver for recovery of the modulation envelope. The
performance network analyzer (PNA) measures the amplitude and phase
of the envelope. For measurements of polarization dependence, the
polarization is scanned by a four-stage, fiber coil (mouse ear) polarization
controller that directly follows the modulator. In summary, two stimuli are
provided by the system: wavelength and state of polarization (SOP). From
the resulting information, the various measurement attributes are
evaluated.
Dual receivers allow simultaneous transmission/reflection testing, or
testing of two test device output ports simultaneously, or comparison of a
test device with a reference device. Some of these setups require an
external coupler or circulator.
Figure 4 86038A Block Diagram
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Agilent 86038A Optical Dispersion Analyzer, Third Edition