40Gb/s DQPSK Receiver
The integrated DQPSK receiver incorporates an optical phase demodulator (delay-line interferometer or DLI) with 2 pairs of balanced photo-diodes and 2 linear TIAs into a single butterfly package. Compared with the currently available discrete solution in which a separate DLI and a separate receiver are used, the integrated DQPSK receiver eliminates labor intensive fiber routing and coupling (between the DLI and the balanced receiver) as well as the skew control. Moreover, the integrated DQPSK receiver offers a smaller footprint suitable for today’s demanding high speed transponder applications.