Numerically-controlled modulated oscillator and modulation method
US5329260A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 17, 1992 |
| Grant date | Jul 12, 1994 |
| Priority date | — |
| Expiry date | Jul 17, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03C3/00
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A numerically-controlled modulated oscillator and modulation method which selectively provides frequency modulation, phase modulation or amplitude modulation with minimal circuitry. A numerically-controlled modulated oscillator is provided having a tuning register for receiving a center frequency parameter, an adder for receiving at one input the frequency parameter, a phase accumulator for receiving a phase increment number from the adder and producing a waveform phase number, a waveform memory for producing a waveform amplitude number in response to the phase number, and a digital-to-analog converter for producing an analog signal in response to the waveform amplitude number. Another input is provided to the adder from an angle modulation register which provides an angle modulation parameter. This parameter can perform either phase or frequency modulation. In the case of frequency modulation, the angle modulation represents the current amplitude of the modulation signal and is added to the center frequency parameter on every clock cycle. In the case of phase modulation, the angle modulation parameter is provided at a periodic rate and then for only one clock cycle. In this case, …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.