Aliasing Ambiguity Explained

[@maximus6884]

Thank you. Your explanations are so valuable and also unique.

[@iain_explains]

Glad you like them!

[@aalselwi]

Thank you for your efforts and time. Is there any relation with the Ambiguity Function of the radar?

[@iain_explains]

In concept, yes, but they are not related mathematically. Here the ambiguity is that for a specific time-sampled signal you can always find multiple continuous-time signals that go through those same sample values at the sample times. In the radar case, the ambiguity is that for a specific radar return you can often find multiple delay-doppler parameter pairs that match the radar return.

[@ashwith]

Just found this channel, thank you for making these videos. I'll be spending some studying them. I wanted to know if you have plans on covering wireline communications too - ISI, linear EQ, etc.

[@iain_explains]

I'm glad you're finding the videos helpful. Thanks for the linear EQ suggestion, I'll add it to my "to do" list. Have you seen the video I've already got on ISI? "What is Intersymbol Interference ISI?" kzbin.info/www/bejne/f2GbaHmLq7xlr9U

[@ashwith]

@@iain_explains I missed this. Thank you so much for pointing this out. Your videos really are helpful. I'm a SerDes design engineer. I was looking for videos to revise things I had studied almost a decade back so thank you for making these. Since my master's focus has been on circuits, it's been a while since I looked at communication concepts.

[@ashwith]

@@iain_explains also if I may ask, what textbook do you recommend for digital communications?

[@iain_explains]

My favourite is J.G. Proakis, “Digital Communications”.

[@ashwith]

@@iain_explains Thank you so much for the book recommendation!

[@georgepalafox5967]

Excellent video. Thanks for putting this video together Sir!

[@iain_explains]

My pleasure! Glad it was helpful.

[@gill6335]

Thank you again for building intuition through your videos. I have one query related to case 1: [Ws > 2Wr]..Here , even we followed Nyquist criteria, still a tone at (ws-wr) shows up in our spectrum while we only had wr in the actual signal. Now, if I do a FFT on the samples and store it in memory and later try to re-construct the signal from FFT samples, Would I be able to reconstruct the original time domain signal or would it look like amplitude modulated signal with tones at Wr and [Ws-Wr]

[@iain_explains]

Always when reconstructing, you need to apply a "reconstruction filter". If your filter is band limited to only pass frequencies below the Nyquist Frequency (ie. half the sampling rate) then the reconstruction will not include the Ws-Wr component. I've just realised that I don't have a video on this yet. Thanks for asking your question. I'm going to put a video on signal reconstruction at the top of my priority list.

[@amitpalkar934]

Great explanation

[@iain_explains]

Thanks. Glad you liked it

[@amitpalkar934]

@@iain_explains within the same example you can probably explain the concept of beat frequency .. A very lucid explanation ..

[@iain_explains]

Thanks for the suggestion. Nice idea. I'll add it to my "to do" list.