Methods and apparatus for offset chirp modulation
US6937108B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 11, 2003 |
| Grant date | Aug 30, 2005 |
| Priority date | — |
| Expiry date | Sep 5, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B2001/6912
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for producing a modulation scheme usable in conjunction with information transmission and reception via waveforms, such as electromagnetic waves. The modulation scheme is usable for such purposes as resolving range ambiguities and overcoming fading and interference problems via use of offset signals that vary in frequency over time (e.g., chirp signals), which spread the signal over a larger bandwidth. The method includes coding a symbol signal onto a split data stream containing a reference signal (e.g., a chirp), to which a time delay has been applied, then recombining the split streams to produce a composite waveform. The method can also include demodulating a composite received waveform by applying a reference signal to the waveform and then band pass filtering the waveform into discrete symbol data. Apparatus and systems are also provided for performing the method.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.