System and method for decryption in the symbol domain
US6035040A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 1997 |
| Grant date | Mar 7, 2000 |
| Priority date | — |
| Expiry date | Oct 17, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04K1/02
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method of decrypting data comprising encrypting bit-wise data, using a first plural bit mask, modulating the data into symbol format, and transmitting the symbol format data to a receiving apparatus, in a receiving apparatus, rotating a current received symbol sample by an amount equal to one of (i) its difference in phase from an immediately preceding received symbol sample toward the phase of the immediately preceding received symbol sample phase, and (ii) by an amount equal to estimated carrier phase towards zero phase, generating a second bit mask subset derived from values of the first bit mask, comprising plural bits for each symbol, reflecting the rotated symbol by a phase defined by the plural bits to form a symbol which is devoid of encryption, and providing the symbol devoid of encryption to a soft-decision decoder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.