Injection locked multi-phase signal generator
US6188291A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 1999 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Jun 30, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45138
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Two or more equal amplitude periodic output signals which are mutually shifted in phase by an integer fraction of 360 degrees, such as 90.degree., are generated by injection locking a ring type oscillator circuit arrangement with a periodic low phase noise signal source. More particularly, a first ring oscillator is injection locked by a low phase noise signal source, one having a noise characteristic which meets the GSM radio standard of at least -132 dBc/Hz at a 3 MHz offset. An identical second ring oscillator is then driven with the output of the first ring oscillator. In one circuit configuration, an even numbered, e.g., a four stage ring oscillator is injection locked to a low-phase noise oscillator having a predetermined noise specification which is application specific and wherein a second even numbered stage, e.g., a four stage ring oscillator is coupled to the first ring oscillator. In a second circuit configuration, a first odd numbered, e.g., three stage ring oscillator, is injection locked to a low phase-noise oscillator and a second odd numbered, e.g., three stage ring oscillator, is injection locked to the first ring oscillator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.