SONET framing recognition using modulation domain analysis

In this letter, we have experimentally studied the synchronous optical netw ork (SONET) data traffic with pseudorandom bit sequence (2(23) - 1) as the data payload in the time domain, spectral domain, and modulation domain. Th e spectral structure of the SONET framing sequence is fundamentally differe nt from that of the random bit sequence of the same length. Based on this o bservation, the SONET framing pulses are experimentally extracted by a modu lation domain analyzer for an OC-48 data traffic. The histogram data shows that the error probability for false framing is 1.7 x 10(-5). The scheme ca n be scaled to higher data rates for performance monitoring applications in all-optical regeneration systems.