Real-equivalent-time oscilloscope and wideband real-time spectrum analyzer

A method of operating a test and measurement device, comprising:

• receiving a signal under test through a channel of the test and measurement device, the channel comprising an input port, a filter, and a sampler;
• producing digital samples of the signal under test at a sample rate using an analog-to-digital converter (ADC), the ADC having two pipes connected to the sampler of the channel;
• acquiring a spectrum of the digital samples for the two pipes in the ADC;
• and
• using the spectrums of the digital samples for the two pipes in the ADC to reconstruct the spectrum of the signal under test.

A method of calibrating a test and measurement instrument operating as a wideband signal analyzer, comprising:

• characterizing pipes of an analog-to-digital converters (ADC) to produce frequency responses of each pipe;
• acquiring a spectrum of digital samples for each pipe in the at least one ADC;
• and
• adjusting the spectrums of the digital samples based upon the frequency responses of each pipe;
• and
• using the adjusted spectrums of the digital samples for all pipes of each ADC to reconstruct the spectrum of signals under test.