Wavelength transmission system and method using 3-dimensional LDPC-coded modulation
US7991070B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 2008 |
| Grant date | Aug 2, 2011 |
| Priority date | — |
| Expiry date | Nov 18, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2025/03611
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A transmitter and method include a LDPC encoder configured to encode source data, and a mapper configured to generate three coordinates in accordance with a 3D signal constellation where the coordinates include an amplitude coordinate and two phase coordinates. A laser source is modulated in accordance with each of the three coordinates to provide a transmission signal. A receiver, includes a demapper receives an input signal from three branches to demap the input signal using a three-dimensional signal constellation having three coordinates. The three branches include a direct detection branch, and two coherent detection branches such that the direct detection branch detects an amplitude coordinate of the input signal and the two coherent detection branches detect in-phase and quadrature coordinates of the input signal. A bit prediction module and at least one LDPC decoder are configured to iteratively decode bits by feeding back extrinsic LLRs to the demapper.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.