The PE4 Series PMD Emulator (Figure 1) produces a controlled amount of polarization mode dispersion (PMD) with high accuracy for fiberoptic systems testing. The PE4 unit emulates PMD. It is a programmable instrument that can be controlled from the front panel or over the built-in RS232 and GPIB interfaces.
A transmitter (Tx) is connected through a polarization controller to the IN port of the PE4emulator. The OUT port of the PE4 emulator is connected to a receiver (Rx).
Typically, the polarization controller is adjusted to launch roughly equal powers into the two internal paths of the PE4 emulator.
As an alternative to changing the polarization state with a polarization controller, the fiber position can be altered or loops can be formed in the fiber.
The PE4 emulator separates the incoming light into two paths, depending on the polarization state. One of the paths passes through an optical delay element; the other path passes through a fixed attenuator. The two paths are recombined at the output of the PE4 emulator.
The PE4 emulator emulates PMD by controlling the path time difference between two polarization states of the input light. The PMD is the difference in path time through the two internal paths and is measured and displayed in picoseconds (ps). The factory-set path time in the two internal paths is equal (for example, zero PMD) when the PE4 emulator is set to the zero position (0.000 ps).
The optics are bidirectional, and therefore either fiber port can be used as the input.
Features
PMD emulator range up to 250 ps
Nominal resolution 0.002 ps
User-adjustable calibration factor
IEEE 488.1 parallel interface
RS232 serial interface
** Call to discuss Optical connector types available
JDS Fitel PE4