Featureless low-probability interception/detection waveform via continuously variable symbol rate transmission
US11159939B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2019 |
| Grant date | Oct 26, 2021 |
| Priority date | — |
| Expiry date | Jan 13, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2021
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Techniques are disclosed for generating a featureless low-probability-of-intercept/low-probability-of-detection (LPI/LPD) waveform via a continuously variable symbol rate transmission. A continuous-phase-modulation (CPM) signal can be represented with a phase trellis. During each symbol duration, the trellis is traversed in either a positive or negative direction in a continuous fashion from the starting phase value to the end phase value. The rate at which the trellis is traversed is varied continuously as a time-varying function. The time-varying phase velocity function, or instantaneous symbol rate, is a type of spreading code or secret key shared between the transmitter and receiver. The disclosed techniques can be implemented with CPM compromising the constant-modulus property of CPM signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.