Linear chirp generation using VCO tuning with polynomial predistortion
US5557241A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 24, 1995 |
| Grant date | Sep 17, 1996 |
| Priority date | — |
| Expiry date | May 24, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B2200/0092
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An ultra-linear chirp generator includes a voltage controlled oscillator (VCO) having a tuning characteristic which is naturally nonlinear, a linear ramp generator which generates a linearly ramping output signal having a linear slope characteristic with respect to time, a polynomial correction waveform generator which generates a polynomial correction signal, and a summer which is responsive to and sums the linearly ramping output signal and the polynomial correction signal. The summer generates a VCO tuning signal for tuning the VCO. The tuning signal corresponds to the linearly ramping output signal predistorted with a nonlinearity opposite to the natural nonlinearity of the VCO tuning characteristic. The linear chirp generator also includes a phase locked loop which is responsive to the output signal of the VCO and which has a reference frequency which is related to the repetition rate of the output signal of the VCO.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.