Amplitude and frequency modulators using a switchable component controlled by data signals
US4320361A · kind A · utility
111Cited by
4References
7Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 3, 1979 |
| Grant date | Mar 16, 1982 |
| Priority date | — |
| Expiry date | Dec 3, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03C2200/005
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A modulated signal source derives its modulation information from digital data held in a data store. The digital data is arranged to operate a switch which in the case of amplitude modulation produces pulses of carrier frequency and in the case of frequency modulation introduces phase transitions into a carrier frequency. The use of the digital data and the switch enables the modulation characteristics of the signal source to be exactly predictable and reproducible and it is not degraded by non-linearities of the kind introduced by conventional mixers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.