Upsampling and Downsampling Example

An example of upsampling and downsampling in a digital filtering problem, tracking the DTFT and FT of the signals after each operation.

[Isabellaa-msdk]

10 years later and still the best video i could find on this topic!

[alexandresolisoares]

This video summarized half of my semester. Thank you!

[allsignalprocessing]

A more complete (and lengthy) way to say this is:" inserting samples whose values are zero." The example involves upsampling by a factor of two, so we insert a sample whose value is zero in between every sample of the incoming signal. This doubles the length of the signal and every other value is now zero. This introduces high frequency components that are removed by the smoothing of the lowpass filter. The "Upsampling" video in the same playlist describes this in more detail.

[yongkinchong]

This is a really great tutorial about the topic of upsampling and downsampling, and I have a small suggestion on 3:06. Noting that Omega_s on the right and on the left have different meanings.

[fkaragoz]

My brain melted halfway through... Thank you

[rohanghige]

These lectures are awesome... After watching these lectures I fill reallly great..Thank you for such good teaching.. :)

[masintec]

precise, understandable, simple, beautiful. Thanks so much~~

[johnpapaeracleous]

Very well presented and easy to follow. Thanks and nice vid!

[YewJiaMing]

The video is very nice and easy to understand

[aricradzin]

At 03:25 you say that T = 1/3000 [sec] means that omega_s [rad/sec] is 6000pi.
I don't understand it. The formula is ( omega_s = (2pi) / T ). So in our case, omega_s should be equal to ~18849[rad/sec].
What am I missing?...

[el-mehdibenchaib]

Thank you for this illustrative video.

[yasserothman]

@4:02 What is the difference between upper and lower case omega ? What transform result each of them ?

[SS-xtul]

Hello Barry. thank you for your videos, one important question: do you have signal processing tutorial with MATLAB? I really need to learn them, I am so frustrated by MATLAB.

[angeleye]

can u please explain how to design the inner filter during the resampling of polyphase fir filter..supose if input sample rate fs bandwidth is bw pasband freq fp and stop band freg is fs and has n tap and 80 db attenuation ... m to 1downsampling and 1 to m upsampling ..

[djolarola]

So, we get doubled Amplitude through the Lowpass filter at the end, not through upsampling? Upsampling shouldn't change amplitude, right?