Three-state digital mixer-driver circuit
US4385401A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 1980 |
| Grant date | May 24, 1983 |
| Priority date | — |
| Expiry date | May 27, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/709
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A mixer-driver circuit in a code correlator of a spread-spectrum communications system simultaneously multiplies an input RF signal with two phase-offset digitally encoded bit streams. A double-balanced mixer is driven with the difference of the digital signals; the mixer is either inverting, noninverting, or off. Matched ECL bistables which reclock the phase-offset bit streams, and a load current steering circuit coupled to the bistables together provide a balanced, differential drive current to the mixer which switches state faster than the bistables alone. In another embodiment, a single bistable receiving an encoded bit stream differentially drives the mixer in a biphase circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.