High isolation mixer
US5303418A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 21, 1991 |
| Grant date | Apr 12, 1994 |
| Priority date | — |
| Expiry date | Jun 21, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D9/0608
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for improved isolation of IF, LO, and RF frequency signals from the non-associated mixer ports (e.g., avoiding introducing RF frequency signals at the IF and LO ports, and similarly vis-a-vis other signals and ports), is provided by coupling a RF (or LO) signal to first ports of four-port first and second phase shift means, each having two signal output ports having 180.degree. phase difference for signals input from the first port, coupling the LO (or RF) signal to the first port of a third phase shift means, with two output signal ports having a phase difference of 180.degree., supplying the third phase shift means output signals to fourth ports of the first and second phase shift means, supplying the output signals of the first and second phase shift means to distinct ports of a five port mixer, and coupling an IF signal from the five port mixer to an IF port.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.