Direct modulation FM data receiver
US4523324A · kind A · utility
32Cited by
6References
3Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 20, 1982 |
| Grant date | Jun 11, 1985 |
| Priority date | — |
| Expiry date | Oct 20, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/148
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A direct modulation FM data receiver including a mixer (14) having a first input for receiving a directly modulated FM signal (f.sub.c .+-..DELTA.f), where .DELTA.f is the deviation and f.sub.c the carrier, and a second input for a local oscillator (20) signal (f.sub.L) having a frequency within the signal channel but offset from the input signal carrier (f.sub.c) by an amount (.delta.f). Demodulating circuits (22 to 30) distinguish between the signalling tones (.DELTA.f+.delta.f) and (.DELTA.f-.delta.f) and derive a data output signal therefrom.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.