... | ... | @@ -12,3 +12,17 @@ In order to digitize analog waveforms there are two common methods used in digit |
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The first method samples the measured signal in real-time. During this method, the oscilloscopes acquires the signal within one trigger event.
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The waveform is basically captured at a defined sample rate and can be immediately displayed after a minimum of samples is available.
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This mode can be used to measure repetitive as well as non-repetitive signals.
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The ETS method requires more than one trigger event in order to fully restore a captured waveform [24].
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This chapter will describe the ETS mode in detail and discusses the limitations as well as the different implementation methods.
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ETS enables a digital oscilloscope to capture signals with a much higher effective sample rate than the actual sample rate of the built-in ADCs.
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Subsequently, the oscilloscope will then be able to measure and display signals with a higher frequency.
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The disadvantages of this method is the fact that the measured signal has to be a periodic signal.
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This means that the shape and amplitude of the waveform has to repeat itself at a certain point in time.
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And these repetitions have to continue until the oscilloscope is able to correctly reconstruct and display the measured waveform.
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Signals measured by the real-time sampling method does not have this restriction. However, most signals generated by man-made machines are indeed repetitive waveforms. |
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