Patent attributes
A system and method are provided for controlling time delay in a multichannel optical transport network transmission device. The method accepts a pair of 2n-phase shift keying (2nPSK) modulated signals via Ix and Qx electrical signal paths, where n>1, and a pair of 2p-PSK modulated signals via Iy and Qy electrical signal paths where p>1. A voltage V1 on the Ix signal path is compared with a voltage V2 on the Qx signal path, and a VOx voltage in generated, which is minimized by adjusting time delay modules in the Ix and Qx signals paths. Likewise, a voltage V3 (Iy) is compared with a voltage V4 (Qy), and a VOy voltage is generated and minimized. Subsequent to minimizing VOx and VOy, the sum of V1 and V2 (V12) is compared with the sum of V3 and V4 (V34), and a VOxy voltage is generated and minimized.