Patent ID: 8219874

Claim:
A transmitter for optical transmissions comprising: at least one low density parity check (LDPC) encoder configured to encode source data; an interleaver to interleave the encoded data; a mapper configured to generate N coordinates, defined by a set of N orthonormal basis functions each representing a dimension, in accordance with an N-dimensional (N-D) signal constellation; and a modulator configured to perform electrical-to-optical conversion in accordance with each of the N coordinates to provide a transmission signal, wherein the mapper determines the corresponding M-ary signal constellation point s i = 1 N ⁢ ∑ j = 1 N ⁢ ϕ i , j ⁢ Φ j ⁡ ( t ) , and wherein φ i,j represents the possible values of the orthonormal basis functions, Φ j (t) represents the set of orthonormal basis functions at the given point in time, and M=2 N .