Patent ID: 9231721
Filing Date: 2016-01-05
CPC Classification: H04J,H04L

Claim Text:
1. In an Optical Transport Network (OTN) device, a method for generating a rate-adaptive OTUk frame, the method comprising: mapping client input data into a set of (n) allocated slots in a rate-adaptive OTUk frame comprising (m) slots, where (n) and (m) are positive integers, and where (n) is less than or equal to (m); determining a channel quality comprising an optical signal-to-noise rate (OSNR) between a transmitter and a receiver; using the channel quality to determine the number of allocated slots in a payload, where a higher channel quality is associated with a greater number of allocated slots; filling the rate-adaptive OTUk frame, comprising (m−n) unallocated slots, using a process selected from the group consisting of: (1) filling the rate-adaptive OTUk frame using parity bits computed from client input data, and (2) filling at least a portion of the rate-adaptive OTUk frame with dummy bits; supplying the rate-adaptive OTUk frame to a physical layer processor; the physical layer processor detecting unallocated slots in the rate-adaptive OTUk frame; discarding some bits in the rate-adaptive OTUk frame, including at least one bit in the unallocated slots, to obtain a transmit bit stream; converting the transmit bit stream into a sequence of modulated symbols using a modulation scheme; and transmitting the modulated symbols on an optical channel, wherein converting the transmit bit stream to the sequence of modulation symbols comprises the modulation scheme being responsive to the number of allocated slots, where a higher order modulation scheme permits a greater number slots to be allocated.