Time domain - tutorial 6: elementary signals

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  • เผยแพร่เมื่อ 27 ธ.ค. 2024

ความคิดเห็น • 85

  • @andifin3172
    @andifin3172 7 ปีที่แล้ว +20

    first of all thx for your awesome videos, they are very easy to understand without being boring.
    in the very end you put the 5 in front of the integral, but you don't use it in your final answer.
    As far as i know, your final answer should be something like 5u(t-2)

    • @Kuchdelan
      @Kuchdelan  7 ปีที่แล้ว +14

      Hey Andi, thank you very much for your feedback. You are absolutely right, the final answer is 5u(t-2). I forgot to write it down. cheers!

    • @badreddinegacem
      @badreddinegacem 3 ปีที่แล้ว

      I think he made a similar mistake in this example here: 7:50

  • @tejobhiru1092
    @tejobhiru1092 3 ปีที่แล้ว +2

    it feels so amazing to understand it finally..!! thank you so much... i was very confused with all the symbols before watching this video.
    now it is crystal clear..!!!!

    • @Kuchdelan
      @Kuchdelan  3 ปีที่แล้ว

      Glad it helped!

  • @jamesbayode1677
    @jamesbayode1677 3 ปีที่แล้ว +1

    How did you arrive at the line equations for the signals in 1:43 and 3:32?

  • @cooper6717
    @cooper6717 6 ปีที่แล้ว +1

    Thanks a lot Iman, your videos have helped me a lot in understanding basic signal processing. I watched your videos a year ago to help me get through my intro signals and systems course, and I am now re-watching to refresh before a real time dsp lab course this fall.

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      Thanks a bunch for your kind comment, Cooper! It is such a great pleasure to hear my videos have been helpful for you. Please recommend them to your colleagues! Cheers!

  • @vinitsrivastava9714
    @vinitsrivastava9714 5 ปีที่แล้ว +2

    Joy to watch....Feeling good after understanding. Thank you

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว +1

      Joy to see you watching all my videos ;) Thank you!

  • @horstigerhorstiger3724
    @horstigerhorstiger3724 5 ปีที่แล้ว +3

    you are saving me right now! thank you so much for this greatly made tutorial man. Keep up the good work! (thumbs up)

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว

      Thank you very much for the feedback ;)

  • @Alii0110
    @Alii0110 7 หลายเดือนก่อน

    AMAZING MAN
    7 years have passed but still very current

    • @Kuchdelan
      @Kuchdelan  5 หลายเดือนก่อน

      Thanks for your kind words and pleasure to help!

  • @thirteenlao443
    @thirteenlao443 6 ปีที่แล้ว +1

    Dear brother, thanks very much, learn more from you, happy every day!

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      Thanks a lot ;)

  • @MASadat-lz9yz
    @MASadat-lz9yz 5 ปีที่แล้ว +2

    Merci Iman jan , you are the best!

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว

      Thanks a bunch!

  • @moussatouhami7567
    @moussatouhami7567 6 ปีที่แล้ว +2

    thanks 4 this clear easy to grasp lecture ,my question is at 11:00 u didnt multiply by 5,
    another question if u have half circle instead of "(t-2)^2" at 3;20 ,whats the equation 4 half a circle

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว +1

      Hi Evan, thanks for the feedback. Yes, you are right, I forgot to multiply it by 5. The equation for circle is x^2 + y^2 = r^2 where r is the constant radius. Cheers!

    • @moussatouhami7567
      @moussatouhami7567 6 ปีที่แล้ว

      @@Kuchdelan thanks man, love u so much already

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      you are very kind, my friend ;)

  • @alonsechan8178
    @alonsechan8178 5 ปีที่แล้ว +5

    Dirac delta function is equal to infinity and not to 1. Because it's integral is equal to 1 and it's width is approaching zero (a width of a single point) it's hight need to be infinity.
    Thank you very much for the videos !

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว

      Hey Alon, thanks for your comment. Technically impulse function is a rectangular function with the width of Delta and the amplitude of 1/Delta when Delta goes to zero. Thus the area under the curve is one. This definition is technically true but hard to digest. It is common to model this with the unit impulse function with the amplitude of 1 at the origin. Hope this clear things up.

  • @libbyoliver3847
    @libbyoliver3847 5 ปีที่แล้ว +1

    At 4:45, how is the function x(t) defined?

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว

      Hi Libby, x(t) is a general function. So, it can be anything such as cosine, exponential, linear, etc. Hope this helps!

    • @libbyoliver3847
      @libbyoliver3847 5 ปีที่แล้ว +1

      @@Kuchdelan Got it. Thanks!

  • @Hoa-yh1kg
    @Hoa-yh1kg 6 หลายเดือนก่อน

    Doroood iman joon aalie so clear❤❤❤

    • @Kuchdelan
      @Kuchdelan  5 หลายเดือนก่อน

      Mamnon az lotfet and pleasure to help!

  • @yogeshghadge5748
    @yogeshghadge5748 6 ปีที่แล้ว +1

    I didn't got one thing, it's OK that integral us a summation but in the above cases the integrand should be summation of d(t) multiplied by dt. I got that d(t) has value 1 at origin but what about dt???

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      Hi Yogesh. Sorry for confusion. Please let me know which example you are talking about.

    • @yogeshghadge5748
      @yogeshghadge5748 6 ปีที่แล้ว

      iman hi sir, I am talking about all the examples which involve integration of some function f with d(t), moreover in our college we have been taught that d(t) function is 1/E at t=0 where E is a very infinitesimally small no.

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      please read page 60 & 61 here:
      www.ece.uvic.ca/~frodo/sigsysbook/downloads/lecture_slides_for_signals_and_systems-2016-01-25.pdf
      Hope this helps!

  • @uniqueramya3632
    @uniqueramya3632 6 ปีที่แล้ว +1

    Thank you for the awesome explanation. I have a doubt, at 8:10 in the video. we have in 2nd example cos(2t)delta(t-1) with integral.
    delta function has t but cos function has 2t. is the 't' in x(t) and delta(t) independent?

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      Thank you very much for the feedback. Regarding your question, no both functions (x and cos) depend on the same variable (t). Hope this helps.

    • @uniqueramya3632
      @uniqueramya3632 6 ปีที่แล้ว +1

      iman thank you! I have almost watched most of your videos and it was really helpful. Currently I'm trying to work on non linear signal processing. Could I email you my query? Please let me know your email. Thanks in advance..

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      Unique Ramya thanks for watching my videos. Please email your questions to imanmoaz@uvic.ca I will do my best to answer them as soon as possible. Best!

    • @uniqueramya3632
      @uniqueramya3632 6 ปีที่แล้ว +1

      iman sure. thank you for the kind response:) God bless!

  • @prakashkumarshah2778
    @prakashkumarshah2778 3 ปีที่แล้ว +2

    Hey Iman thanks for this course, it is really very helpful. Btw is there any chance of getting your notes on blackboard slides in any format.

    • @Kuchdelan
      @Kuchdelan  2 ปีที่แล้ว +1

      I will release them sometimes in the future. Thanks for your feedback!

  • @artsiomkaliaha5578
    @artsiomkaliaha5578 5 ปีที่แล้ว +1

    this is a brilliant video! double thumb up!

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว

      You are awesome ;)

  • @jonathan8295
    @jonathan8295 2 ปีที่แล้ว

    You are a life saver!!!!!!!!!!!!!!!!

    • @Kuchdelan
      @Kuchdelan  2 ปีที่แล้ว

      Glad I could help!

  • @한상우-p8t
    @한상우-p8t 5 ปีที่แล้ว +1

    Thank you for the video but seems weird... how can integral of a point of value 1 (no width) be equal to 1?

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว +1

      Hey. Sorry for the confusion! The value of delta function is actually 1/delta for a width of delta when delta approaches zero. This is a rectangle with the area equal to one. Hope this makes sense.

    • @abbasbookwala
      @abbasbookwala 3 ปีที่แล้ว

      The impulse is 1 and not value of the function. ..meaning the area of this function is one....this point cannot be over emphasized and is source of confusion in beginning for most.

  • @pkl520
    @pkl520 7 ปีที่แล้ว

    can I ask a question iman? in the video at 3:20 , when the equation in the below adding together. the value in the origin is 2 , not as shown in the triangular which u plot in the begin?

    • @Kuchdelan
      @Kuchdelan  7 ปีที่แล้ว +1

      Hey, sorry for my late reply! I have been super busy with life, my friend.
      I just wonder how you ended up with two. Assuming unit step is 1 at the origin, here is what we get:
      (t+1) x (u(t+1) - u(t)) + (-t+1) x (u(t) - u(t-1)) ---> (replace t by zero)
      1 x (u(1) - u(0)) + 1 x (u(0) - u(-1)) = 1 x (1-1) + 1 x (1-0) = 1
      Hope this helps.

    • @pkl520
      @pkl520 7 ปีที่แล้ว +1

      ohhhhhhh~! I see! . I misunderstand the calculate process, but now I get it. tks for ur kind reply iman~

    • @Kuchdelan
      @Kuchdelan  7 ปีที่แล้ว +1

      Not a problem at all ;)

  • @igotsth
    @igotsth 6 ปีที่แล้ว

    5:29 x(t0) is a value of the function x(t) at (t0) which I think it is just a point. why is it a line?

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      Hey, thank you for the question. Note that "y = constant" is a line parallel to the x-axis. No matter what x is, the y value is always constant. Hope this makes sense.

  • @ionni73
    @ionni73 8 ปีที่แล้ว

    Hi Iman. Thanks for this (again very good explained) video. I still have a basic question on the equivalence and sifting properties of the delta functions. The "mechanics" of the examples are clear, but where I am not 100% clear is what are these properties of the delta function good for. Referring to your examples at ca 11:00 . What are you proving by multiplying sin(t) with d(t-pi/6) and resulting in 1/2d(t-pi/6)? Thanks again for the time doing these videos!

    • @Kuchdelan
      @Kuchdelan  8 ปีที่แล้ว +1

      Hi again Jonathan. Thank you for your question. The sifting and equivalence properties are super useful in signal processing. That's why I decided to dedicate one lecture to this topic. If you keep watching my tutorials, you will see the applications of these properties in convolution, Fourier series/transform and sampling. For instance, multiplying sin(t) with d(t-pi/6) means sampling the sinusoidal function at pi/6. Please let me know if you still have more questions. Cheers!

  • @MaxTube123456
    @MaxTube123456 5 ปีที่แล้ว +3

    Dirac delta function is NOT equal to 1 at t=0: it equals to infinity. But an integral of Dirac delta function is 1. It is very important to understand, but it is shown wrong in this video and some next too.

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว +1

      Hey, thanks for your comment. Technically impulse function is a rectangular function with the width of Delta and the amplitude of 1/Delta when Delta goes to zero. Thus the area under the curve is one. This definition is technically true but hard to digest. It is common to model this with the unit impulse function with the amplitude of 1 at the origin. Hope this clear things up.

  • @linhnguyen-ue2xd
    @linhnguyen-ue2xd 5 ปีที่แล้ว +1

    Hi Iman, appreciate the videos, they are of great help!
    I'm a bit confuse at 8:00, example 2, as you went a bit too fast, this is my understanding of what happen, and I think it's missing, hope you could provide some clarification:
    cos(2t)∆(t-1) = cos(2 * t)∆(t-1) = cos(2 * 1) = cos(2)

    • @Kuchdelan
      @Kuchdelan  4 ปีที่แล้ว

      Hey! Thanks for your comment and sorry for the late reply. Life has been hectic recently! You got it all right. I just replaced t by 1. Hope it makes sense.

    • @badreddinegacem
      @badreddinegacem 3 ปีที่แล้ว

      @@Kuchdelan shouldn't it be cos2 * U(t-1)

  • @yevhenbaidiuk8695
    @yevhenbaidiuk8695 4 ปีที่แล้ว +1

    Which program you use for drawing?

    • @Kuchdelan
      @Kuchdelan  3 ปีที่แล้ว

      I used to use photoshop but now I am using Castofly!

  • @tıbhendese
    @tıbhendese 2 ปีที่แล้ว +1

    I guess you did wrong at 4:27 , impulse function is never 1, it is infinity. The area is 1.
    unit impulse function and unit impulse sequence ( DT ) are not same. There is an abstract "impulse to sequence" conversion. It will be helpful if you make a video about CT to DT conversion, about what exactly the process is.
    Also, your solutions could be slower. Thanks

  • @Andrei-ds8qv
    @Andrei-ds8qv 7 ปีที่แล้ว +1

    thanx man!! very nice videos!!

  • @binshuaiwang5714
    @binshuaiwang5714 6 ปีที่แล้ว +1

    Hi iman, I like your video very much and I hope you can continue to make it. Besides, at 6:54 in this video, it seems that you forgot the dt in the Integral formula.

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว

      Thank you very much for the feedback, Binshuai. You are very nice. And yes, I forgot dt in the integral. Sorry for the confusion. Best!

  • @HamidAzad23
    @HamidAzad23 3 ปีที่แล้ว +1

    sepas Iman!

    • @Kuchdelan
      @Kuchdelan  3 ปีที่แล้ว

      Mamnonam dooste aziz!

  • @chunlokli7704
    @chunlokli7704 6 ปีที่แล้ว +3

    clear af

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว +1

      hahaa, thanks dude ;)

  • @area51xi
    @area51xi 3 ปีที่แล้ว

    If it doesn't matter what you call the integral variable then why not refer to it as t dt instead of tau dtau?

    • @Kuchdelan
      @Kuchdelan  3 ปีที่แล้ว

      Because I already used t in the integral which is different from tau

  • @JT-hp1eo
    @JT-hp1eo 6 ปีที่แล้ว

    nice video! The example in the end, i am not so clear, how to deal with the 5?

    • @Kuchdelan
      @Kuchdelan  6 ปีที่แล้ว

      Thank you! You are right, the final answer is 5u(t-2). I forgot to write it down. cheers!

  • @cvbbb5
    @cvbbb5 4 ปีที่แล้ว +1

    Your vids are amazing I LOVE IT but can u also please teach about Energy and power signal please and also LCDE and State variable. Thx for your great vids 10000 times better at explaining compare to my professor at university and I'm also sharing this great content to my friends Pls keep up the good work XD
    and btw I'm wondering why won't u teach discrete time since they are similar but important too

    • @Kuchdelan
      @Kuchdelan  4 ปีที่แล้ว

      Hey. Thanks a lot for your feedback and kindness. I will cover more videos very soon. Cheers!

  • @seventyfive7597
    @seventyfive7597 4 ปีที่แล้ว

    Hi, the way you defined the impulse function, it's integral is always zero, because you chose a finite value for t=0, and therefore that finite number over an infinitesimal width has zero area. You can multiply it by any finite function and it will remain zero. For a proper definition refer to wiki under the definition section: en.wikipedia.org/wiki/Dirac_delta_function#Definitions

    • @seventyfive7597
      @seventyfive7597 4 ปีที่แล้ว

      Why not correct with an annotation?

  • @Lestibournes
    @Lestibournes 5 ปีที่แล้ว

    I think it would be clearer it would be wrong to leave out the delta if you wrote:
    x(t)=sin(t)*∆(t-t0)=>x(t)=sin(t0)*∆(t-t0)
    Because then withouy delta you get:
    x(t)=sin(t0)
    So the signal x(t) is equal to a constant.

    • @Kuchdelan
      @Kuchdelan  5 ปีที่แล้ว

      Yep, that's correct. As explained in the video, the delta function cannot be left out. Cheers!

  • @rayaneaboud9043
    @rayaneaboud9043 2 ปีที่แล้ว

    thank you for the video but I think that the last answer=5 if t>=0

  • @faris7401
    @faris7401 7 ปีที่แล้ว +1

    thank you x100000000000000000000000000000000000000000000

    • @Kuchdelan
      @Kuchdelan  7 ปีที่แล้ว

      You are very welcome Faris ;)

  • @meliodassama695
    @meliodassama695 2 ปีที่แล้ว +1

    university is really useless....all you need
    X(Iman)/teacher.Done

    • @Kuchdelan
      @Kuchdelan  2 ปีที่แล้ว +1

      loll! thank you ;)