Optimal trellis code design for QPSK and higher order quadrature amplitude modulations
US7379504B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2002 |
| Grant date | May 27, 2008 |
| Priority date | — |
| Expiry date | Apr 21, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/3427
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A wireless device and system employs a two-dimensional (2-D) Trellis code that can be applied to Quadrature Phase Shift Keying (QPSK) and higher order Quadrature Amplitude Modulation (QAM) constellations. The Trellis codes employed have optimal Euclidean distance properties for QPSK constellations, and have very good Euclidean distance properties for higher-order QAM constellations. The Trellis codes are suited for transmission systems that adopt multi-mode QPSK and QAM constellations with different data rates since the same Trellis code can be applied to all modulation formats and the same decoder can be used at the receiver for all modulation formats. Modulation formats include QPSK, 8-QAM, 16-QAM, 32-QAM, and 64-QAM and may be extended to even higher order modulations formats.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.