Tektronix DSA8300, Service Manual

Page: 31 / 138

Theory of Operation
80C03 Optical Sampling
Module
The 80C03 module supports conformance testing of both short and long bandwidth
(700-1650 nm) signals at 1.063, 1.250, and 2.488 Mb/s as well as general purpose
testing with >2.3 GHz optical bandwidth. Its ampli
fi ed optical to electrical
converter design enables the user to examine very low-level optical signals.
OC48: The electrical sampler is adjusted to approximately 12.5 GHz (-3 dB)
bandwidth and signal is not routed through any
fi lter (signal is sent through
the straight-through path). The O/E converter is designed by the vendor to
match the OC48 reference receiver response curve. The span adjustment
provides limited adjustment of the frequency response. It is adjusted at the
factory so that the combined system will have an OC48 (STM-64) Reference
Receiver response. This mode is synonymous with the 2.3 GHz maximum
bandwidth setting.
FC1063: The electrical sampler is adjusted and O/E converter span voltage
are the same values as in the OC48 mode. The signal is routed through a
hardware
fi lter designed to result in the combined system having an FC1063
(1.0625 Gb/s Fibre Channel) Reference Receiver response.
GBE: The electrical sampler is adjusted and O/E converter span voltage are
the same values as in the OC48 mode. The signal is routed through a hardware
fi lter designed to result in the combined system having an GBE (1.25 Gb/s
Gigabit Ethernet) Reference Receiver response.
The 80C03 module can be con
fi gured with clock recovery that supports Fibre
Channel 1063 (1.063 Gb/s) and OC-48 / STM-16 (2.488 Gb/s) standards.
80C04 Optical Sampling
Module
The 80C04 module is optimized for testing of long wavelength (1100-1650 nm)
signals at either 9.953 Gb/s or 10.664 Gb/s. With its high optical bandwidth
>28 GHz, it is also well suited to general-purpose, high-performance optical
component testing.
OC192 or 10.664 Gb/s: The electrical sampler is adjusted to give the desired
response, and signal is not routed through any
fi lter (signal is sent through
the straight-through path). The sampler bandwidth and response is optimized
during the calibration such that the combined system will have an OC192
(STM-64) or 10.66 Gb Reference Receiver response.
20 GHz: The sampler bandwidth and response is set during the calibration
such that the combined system will have an Optical Bandwidth (-6 dB)
>20 GHz.
30 GHz: The sampler bandwidth and response is set during the calibration
such that the combined system will have an Optical Bandwidth (-6 dB)
>28 GHz.
The 80C04 can be optionally con fi gured with clock recovery (Opt. CR-1) that
supports 9.953 Gb/s telecom standards.
DSA8300 Digital Serial Analyzer and Modules Service Manual 2–9