User`s guide

Capturing Data 3
Agilent 1000 Series Oscilloscopes User’s Guide 67
Oscilloscope Bandwidth and Sample Rate
An oscilloscope’s bandwidth is typically described as the lowest frequency
at which input signal sine waves are attenuated by 3 dB (- 30% amplitude
error).
At the oscilloscope bandwidth, sampling theory says the required sample
rate is f
S
=2f
BW
. However, the theory assumes there are no frequency
components above f
MAX
(f
BW
in this case) and it requires a system with
an ideal brick- wall frequency response.
Figure 26 Alaising