Patent ID: 7209937

Claim:
An apparatus comprising a waveform generator which digitally synthesizes a waveform having a plurality of successive portions that can each be as short as one of a mono-cycle of said waveform and a part of a mono-cycle of said waveform, said waveform generator changing at least one of a frequency, a phase and an amplitude of said waveform between each successive pair of said portions thereof, wherein said waveform generator includes: a digital accumulator having a first input responsive to a frequency coefficient, having a second input, and having an output coupled to said second input; a digital adder having a first input responsive to a phase coefficient, having a second input coupled to said output of said accumulator, and having an output; a digital sine generator having an input coupled to said output of said adder, and having an output, said sine generator producing at said output thereof a value which is the sine of a value at said input thereof; and a digital multiplier having a first input responsive to an amplitude coefficient, having a second input coupled to said output of said sine generator, and having an output.