Coded digital modulation method for communication system
US7239668B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 24, 2006 |
| Grant date | Jul 3, 2007 |
| Priority date | — |
| Expiry date | May 24, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/3411
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A new class of 16-ary Amplitude and Phase Shift Keying (APSK) coded modulations, called double-ring APSK modulation, based on an amplitude and phase shift keying constellation in which the locations of the digital signals to be encoded are placed on two concentric rings of equally spaced signal points. The APSK constellation parameters are optimised so as to pre-compensate the impact of non-linearities. The new modulation scheme is suited for being used with different coding schemes. It is shown that, for the same coding scheme, pre-distorted double-ring APSK modulation significantly outperforms classical 16-QAM and 16-PSK over a typical satellite channel, due to its intrinsic robustness against the high power amplifier non-linear characteristics. The proposed coded modulation scheme is shown to provide a considerable performance advantage for future satellite multi-media and broadcasting systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.