Sampling & AliasingNyquist's condition, where aliases land, and why the filter has to come first.Electrical EngineeringSampling below twice the highest frequencypresent folds that content down as an alias.f_s > 2 f_max · f_alias = |f − k f_s|5 kHz at f_s = 8 kHzAlias at 3 kHz8 − 5.Audio to 20 kHz44.1 kHz samplingRoom for the filter.Exactly 2 f_maxNot enough in practiceNo filter is ideal.THE COMMON MISTAKEFiltering the aliases out after the converterFiltering in analogue, before the samplerOnce folded, an alias sits at a perfectly legitimate frequency and no laterprocessing can separate it from real signal.Oversampling buys a gentler anti-alias filter, never the absence of one.The filter is always analogue and always first.Sampling & Aliasinglearnposters.com
Sampling & Aliasing — printable engineering wall chart from LearnPosters. Free vector PDF, US Letter and A4.

What’s on the Sampling & Aliasing poster

The rule, 3 worked examples, and the mistake everyone makes.

Oversampling buys a gentler anti-alias filter, never the absence of one. The filter is always analogue and always first.

Questions about the Sampling & Aliasing poster

What’s on the Sampling & Aliasing poster?
The rule, 3 worked examples, and the mistake everyone makes. Sampling below twice the highest frequency present folds that content down as an alias.; f_s > 2 f_max · f_alias = |f − k f_s|; 5 kHz at f_s = 8 kHz = Alias at 3 kHz; Audio to 20 kHz = 44.1 kHz sampling; Exactly 2 f_max = Not enough in practice; Common mistake: Filtering the aliases out after the converter → Filtering in analogue…. Oversampling buys a gentler anti-alias filter, never the absence of one. The filter is always analogue and always first.
Who is the Sampling & Aliasing poster for?
Sampling & Aliasing belongs to the Electrical Engineering section rather than to a school year, because engineering is not something one grade owns. Anyone learning signals & systems can pin it up — a beginner, a student mid-course, or someone revising years later.
When should you use the Sampling & Aliasing poster?
Apply it before choosing a sampling rate, and again before choosing the anti-alias filter. A wall chart earns its place by being glanceable from where the work is happening, so Sampling & Aliasing belongs on the wall where that engineering work actually happens, within glancing distance, rather than filed away.
What other posters go with Sampling & Aliasing?
Filter Responses, Bode Plots and Convolution sit alongside Sampling & Aliasing in the Electrical Engineering section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.Filter ResponsesBode PlotsConvolution
Is the Sampling & Aliasing poster free to download and print?
Yes. Sampling & Aliasing downloads as a free PDF with no account, no email and no watermark, like everything else in the Electrical Engineering section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
What size does the Sampling & Aliasing poster print at?
Sampling & Aliasing is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Sampling & Aliasing loses nothing.Printing guide

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