Radio transmission timing calibrator
US6829229B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 2000 |
| Grant date | Dec 7, 2004 |
| Priority date | — |
| Expiry date | May 12, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/0682
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A signal calibrator (14) for a software-defined communications device (10) that enables device communications signals to be transmitted in a manner that maximally decouples the calibrator (14) from the device hardware (40), and that simplifies the design and reduces the cost of the communications device (10). The calibrator (14) includes a software modulator (16) for generating a nonstop stream of samples including zero valued samples and non-zero valued waveform bursts, and a software demodulator (18) connected to the software modulator (16) via a closed loop feedback path (20) that receives a nonstop stream of samples. The non-zero valued samples create radio emissions. The software demodulator (18) is for determining a timing error of the transmission sample and for transmitting a timing error correction value to the software modulator (16) via the closed loop feedback path (20). The timing error correction value enables the software modulator (16) to adjust a transmission time of a subsequent waveform burst to compensate for both unknown hardware delays and RF signal propagation delays.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.