Local oscillator with non-harmonic ratio between oscillator and RF frequencies using pulse generation and selection
US7756487B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 2007 |
| Grant date | Jul 13, 2010 |
| Priority date | — |
| Expiry date | Jan 13, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K5/1565
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A novel and useful apparatus for and method of local oscillator (LO) generation with non-integer multiplication ratio between the local oscillator and RF frequencies. The LO generation schemes presented are operative to generate I and Q square waves at a designated frequency while avoiding the well known issue of harmonic pulling. The input signal is fed to a synthesizer timed to a rational multiplier of the RF frequency L/N fRF. The clock signal generated is divided by a factor Q to form 2Q phases of the clock at a frequency of L(N*Q)fRF, wherein each phase undergoes division by L. The phase signals are input to a pulse generator which outputs a plurality of pulses. The pulses are input to a selector which selects which signal to output at any point in time. By controlling the selector, the output clock is generated as a TDM based signal. Any spurs are removed by an optional filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.