FSK data receiving system
US5414736A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 1992 |
| Grant date | May 9, 1995 |
| Priority date | — |
| Expiry date | Aug 7, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/152
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An FSK data receiving system is provided which is capable of constituting a direct-conversion receiver suitable for realizing an integrated circuit, is capable of decoding in a wide receiving band width, and is capable of realizing a small-sized and less-electric power consumption data receiving. An FSK-modulated local oscillator signal 3 is applied to a local oscillator 2, and there is provided a decode circuit 15 which obtains the decode signal 14 by judging whether the FSK-modulated frequency deviation of the carrier wave signal 1 is a positive deviation or a negative deviation on the basis of a comparison result of a voltage change in a frequency-voltage conversion circuit 16 for a base-band signal 8; i.e. the output signal of a frequency mixer 6. An offset amount of the local oscillator frequency is judged by a voltage judging circuit 17 to produce a control signal 18 Further, there is provided another decode circuit 22 which makes a judgement of frequency change of the base-band signal 8 and a judgement of in-phase/opposite-phase relationship from the decode signal 14 and the output of the voltage judging circuit 17 so as to obtain a decode signal 23. Moreover, there is provi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.