Technique for demodulating a linear modulated data signal in a communications system
US6904104B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1999 |
| Grant date | Jun 7, 2005 |
| Priority date | — |
| Expiry date | Sep 10, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2332
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A receiver section recovers the in-phase and quadrature components of a linear modulated data signal. The in-phase signal is sampled and quantized producing an in-phase sample stream, and the quadrature phase signal is sampled and quantized producing a quadrature sample stream. The in-phase sample stream and the quadrature sample stream are both over-sampled at a rate of N times a symbol rate of the data signal. A decimation section filters the quantized in-phase sample stream and the quantized quadrature sample stream to produce a reduced in-phase sample stream and a reduced quadrature sample stream at a rate of M times the symbol rate, wherein M is less than or equal to N. A decision component calculates the magnitude of a combination of an in-phase sample and a quadrature sample at M corresponding sample points in the reduced in-phase sample stream and the reduced quadrature sample stream, respectively, and then forms an in-phase symbol stream and a quadrature symbol stream using the in-phase sample and the quadrature sample, respectively, associated with the sample point having a largest magnitude.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.