Piecewise coherent, combined frequency and phase-shift-keyed signal demodulator
US4247943A · kind A · utility
6Cited by
6References
4Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 21, 1979 |
| Grant date | Jan 27, 1981 |
| Priority date | — |
| Expiry date | May 21, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/32
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system for demodulating piecewise coherent, combined frequency and phase-shift-keyed signals that are modulateed by orthogonal or biorthogonal code words. Rather than maintain local reference signals in phase-lock with the received signal, the system mixes the received signal with both sine and cosine signals at both the mark and the space frequencies to obtain multiple outputs which are correlated with each of the code words utilized by the system to determine the particular code words that have been received.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.