Patent ID: 7728691
Filing Date: 2010-06-01
Classification: G01R

Abstract:
1. A modulator designed as a completely digital modulator for radio-frequency signals, comprising: a first mixer stage; a first modulation signal and a first oscillator signal supplied to the first mixer stage with a first sample rate; the first mixer stage mixing the first modulation signal and the first oscillator signal into a first intermediate signal and outputting the first intermediate signal with the first sample rate; the first oscillator signal being generated by a first oscillator; the first oscillator having a first phase accumulator and a phase-amplitude transducer; the first oscillator signal having a first oscillator frequency; the first oscillator frequency being determined by a first incremental value by which a content of the first phase accumulator is incremented between two readout processes in immediate succession; the first incremental value having a first bit width; the modulator has a first sample rate transducer; the first intermediate signal with the first sample rate being supplied to the first sample rate transducer; the first sample rate transducer outputting the first intermediate signal with a second sample rate that is greater than the first sample rate; the modulator having a second mixer stage; the first intermediate signal and a second oscillator signal being supplied to the second mixer stage with the second sample rate; the second mixer stage mixing the first intermediate signal and the second oscillator signal into a first final signal and outputting the first final signal with the second sample rate; the second oscillator signal being generated by a second oscillator; the second oscillator having at least one second phase accumulator and a second phase-amplitude transducer; only one of the phase accumulators acting on the phase-amplitude transducer; the second oscillator signal having a second oscillator frequency that is greater than the first oscillator frequency; the second oscillator frequency being determined by a second incremental value by which a content of the second phase accumulator acting on the phase-amplitude transducer is incremented between two readout processes in immediate succession; and the second incremental value having a second bit width that is smaller than the first bit width.