DGD-1000
First Order PMD Source / Emulator

Polarization mode dispersion (PMD) can
seriously degrade the quality of high speed fiber optic data transmission. High speed transceivers must meet stringent standards for PMD tolerance. The
DGD-1000 accurately and repeatably generates both high and low values of differential group delay (DGD) or first order PMD. Both the DGD and PDL are very stable over time and wavelength within the performance band. This instrument is available in
different versions to accommodate the need for different wavelength and DGD ranges.



Applications
• System PMD Tolerance Testing
• 1st order PMD Performance Simulation

Figure 2 : (a) Typical DGD accuracy plots show
high accuracy over the entire DGD range. The DGD error (deviation from set
value), measured with a 5-sample average, is less than 0.1ps. (b) The
repeatability plot show less than 0.1ps variability over 5 repeated
measurements of DGD values over the entire DGD range. Max ΔDGD = highest measured value – lowest measured value over 5 measurement
at the same setting. (c) PDL vs DGD measurements show that the PDL is
both low and relatively constant over the DGD range. For both test instruments,
PDL was < 0.1dB over full DGD range with less than 0.03dB PDL variation. (d)
IL vs DGD measurements show  that the
IL is relatively constant over DGD range. Gor both units IL variation over the
DGD range is less than 0.1 dB.