Multidimensional Signaling and Coding Enabling Multi-Tb\/s Optical Transport and Networking: Multidimensional aspects of coded modulation

High-speed continuous-variable quantum key distribution over atmospheric turbulent channels

“…6. The reconciliation efficiency in use has been realized by the LDPC codes [21,22].The maximum SKR of >20 Mbit⁄s can be obtained when T=0.85, and V A = 0.35. We find that the SKR of >4 Mbit⁄s can be obtained when T=0.55, and the minimum transmittance of T= 0.35 is required to guarantee secure CV-QKD transmission.…”

Adaptive multidimensional modulation and multiplexing for next generation optical networks

“…In some cases orthogonal polynomials, or orthogonal prolate spheroidal wave (OPSW) functions can be used instead of orthogonal subcarriers, [25]. As an example, if OPSW are used as orthonormal basis functions { j } in Eqn.…”

“…2a. For instance, for each polarization state, we can employ M electrical basis functions, such as in the scheme with M orthogonal subcarriers, and then construct O-OFDM superchannels, align several of them in an orthogonal manner, and then load this spectral content on selected number of spatial modes, as proposed in [25]. …”

“…We should outline that the coding gain for the next generation of FEC schemes will exceed 12 dB while keeping coding rate for not falling below 0.8. Some attractive classes of LDPC codes, such as quasi-cyclic (QC), convolutional, staircase, and spatially coupled ones, which are suitable for multidimensional optical communications have been presented and analyzed in [25].…”

“…As already mentioned, the FEC coding can be applied in parallel with modulation process, and such process is known ad coded modulation one, [5], [25], [38]. The key advantage of coded modulation schemes is in higher level of parallelization since the main functions that involve an intense DSP are effectively performed at much lower symbol rates as compared with alternatives.…”