Josephson junction FSK demodulator
US5039951A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1990 |
| Grant date | Aug 13, 1991 |
| Priority date | — |
| Expiry date | Oct 30, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/148
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A Josephson junction (100) is employed as a very-high-speed frequency demodulator for detecting a frequency-shift-keyed (FSK) modulated signal (201) in a microwave or lightwave communication system. The voltage induced across the junction in response to an incident FSK modulated radiation signal follows the frequency variations in the incident wave thereby directly demodulating the information signal from its carrier. In the disclosed embodiment an FSK modulated optical signal is mixed with a local oscillator (303) signal, which is then incident on a photodetector (305). The resultant microwave-frequency signal is then applied over a two-wire transmission line (308) to the Josephson junction (307) for direct demodulation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.