07 | Keysight | N4917B Optical Receiver Stress Test Solution - Solution Brochure
N4917B Detailed Test Setup
The core instrument of the optical stressed eye test setup is the J-BERT M8020A High-
Performance BERT system that provides an electrical signal with all the required impairments
(random and sinusoidal timing jitter, ISI and sinusoidal amplitude interference) at the data
signal output, using a combination of its built-in stress sources plus an external generator.
This electrical signal is fed into the 81490A electrical-optical converter to modulate the laser
and create the stressed optical signal. For LR4/ER4, an 8160xA tunable laser is used to set the
wavelength for each of the four lanes in turn. For SR4, all lanes operate at a fixed wavelength,
using the 81490A internal laser source. The optical output of the 81490A is then attenuated to
get to the required optical power level at the input of the receiver under test.
Prior to testing the receiver, the optical signal for each wavelength is calibrated using the
86100D Infiniium DCA-X Wide-Bandwidth Oscilloscope with 86105D optical module or using
the N1092x DCA-M. All of the equipment is under control of the N4917B software, which
takes care of the various equipment settings and performs an iterative adjustment of the
BERT stressess until the optical signal measured on the DCA meets the required stressed eye
parameters (ER, VECP/SEC, J2, J4/J9, Eye Mask).
Figure 5. Example connection diagram for 100GBASE-LR4/ER4 single-mode optical receiver stress test solution.