Patent ID: 7970285

Claim:
A method for calibrating temporal skew in a multichannel optical transport network (OTN) transmission device, the method comprising: accepting a pair of 2 n -phase shift keying (2 n -PSK) modulated signals via Ix and Qx electrical signal paths, where n>1; accepting a pair of 2 p -PSK modulated signals via Iy and Qy electrical signal paths where p>1; converting the 2 n -PSK and 2 p -PSK signals to 2 n -PSK and 2 p -PSK optical signals, respectively; multiplexing orthogonally polarized 2 n -PSK and 2 p -PSK optical signals; transmitting the orthogonally polarized signals; generating a timing voltage responsive to detecting the intensity of the orthogonally polarized signals; correlating the timing voltage to a reference frame calibration pattern associated with a preamble/header portion of an OTN frame; comparing timing voltages associated with the Ix, Qx, Iy, and Qy signal paths; and, minimizing misalignment between the timing voltages and the reference frame calibration pattern in response to adjusting time delay modules in the Ix, Qx, Iy, and Qy signal paths.