High bandwidth oscilloscope

摘要

A method for improving bandwidth of an oscilloscope involves, in preferred embodiments, the use of frequency up-conversion and down-conversion techniques. In an illustrative embodiment the technique involves separating an input signal into a high frequency content and a low frequency content, down-converting the high frequency content in the analog domain so that it may be processed by the oscilloscope's analog front end, digitizing the low frequency content and the down-converted high frequency content, and forming a digital representation of the received analog signal from the digitized low frequency content and high frequency content.

主权项

1. A method for digitizing an analog signal, comprising the steps of:
separating an analog signal spanning a frequency range into a first signal occupying a first frequency band and a second signal occupying a second frequency band, at least a substantial portion of said second frequency band being higher than the first frequency band; translating the second signal to a lower frequency band; digitizing the translated second signal with digitizing elements having a frequency range less than the analog signal frequency range; digitizing the first signal; and forming a digital representation of the analog signal from the digitized first signal and the digitized second signal, the digital representation substantially spanning the frequency range of the analog signal.