Method and apparatus for extraction of baseband waveform from amplitude modulated signal via time domain sampling

A measurement apparatus, for example a digital oscilloscope, receives an amplitude modulated (AM) signal comprising a baseband signal, having a baseband waveform, modulating a carrier signal, and reconstructs the baseband waveform. The measurement apparatus: samples the AM signal at a sampling rate which produces a plurality of data samples for each period of the carrier signal; determines the amplitude of the baseband signal for each of a plurality of periods of the carrier signal from at least some of the plurality of data samples for each period; and reconstructs the baseband waveform from the amplitudes of the baseband signal for each of the plurality of periods of the carrier signal. The measurement apparatus may display the reconstructed baseband waveform on a display device.