Foreword
All oscillograph have an undesirable character: Front of consist in oscillograph and the perpendicular noise in digitlizing a process. Measure systematic noise to measure the concrete signal that drops you precision, when measuring low n signal and noise especially. Because oscillograph is a kind of broadband,measure an instrument, oscillograph bandwidth is wider, noise of most circumstance prolapse is louder also. The perpendicular noise that although the engineer is in,oscillograph can understand when buying oscillograph is characteristic, but should undertake careful assessment to these character, because it can affect signal integrality via a few kinds of ways. Perpendicular noise meets:
1. Introduce extent to measure an error
2. Introduce Sin(x)/x weaveform to rebuild to be not spent certainly
3. Introduce the time error that as input signal edge pressing places rate function (shake)
4. Those who cause considerable examine to arrive is undesirable " fat " undee
Be not all oscillograph manufacturer to give out in technical data regrettablly perpendicular noise index / characteristic. Although have this index, it often also can cause misdirect, and be half-baked. The article compared Agilent, Tektronix and LeCroy place to make 500MHz come the perpendicular noise of oscillograph of 1GHz bandwidth limits is characteristic. In addition still told about measure systematic noise relatively high when existence (oscillograph noise) when n, how to believe the useful skill that date undertakes more accurate noise and interference are measured to low n.
What is noise, answer how to measure noise
Random noise also weighs white noise sometimes, it is in theoretic do not have a bound, obedient gauss distributings. Without the random sex that because noise is inherent,the bound means, you are measured in noise token in collect data more, can get jumping over tall summit summit deflection. As a result of this one reason, mix like perpendicular noise shake randomly this kind of random phenomenon should use virtual value (standard deviation) undertake define and be metricaled. Express the 1 virtual value that shows an oscillograph of bandwidth of 500MHz of 4 kinds of competition noise background measured value. Oscillograph of avery kind of is used 50ΩTermination, set the highest sampling rate that sets to use each oscilloscope, falling without signal join condition collect weaveform.
Also consult please the background of virtual value noise of oscillograph of bandwidth of 1GHz of the competition in appendix A measures an outcome.
Think normally of oscillograph " background of base line noise " it is oscillograph park the most acute setting (lowermost V/div) the noise n when. But the bandwidth that a lot of oscillograph on the market reduce from time to tome in setting of the most acute V/div today is characteristic. The place before be like is narrated, oscillograph is instrument of a kind of broadband, bandwidth is taller, noise background is normally taller also. Compare each oscillograph in you so when the most acute V/div installs the character of background of base line noise of place, you may be making inferior bandwidth oscillograph and taller bandwidth oscillograph quite, this is not congener thing quite. The background of base line noise that should provide the setting of the most acute V/div of complete bandwidth to be in more identical bandwidth in each oscillograph.
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