Good stuff

Dear Mrs. Rusch, First of all thank you for this great video. I don‘t know whether you will read this but I have a bit of a problem understanding why 2D-QAM shouldn‘t be possible with just IM/DD. Looking at WiFi QAM demodulation can be performed in DSP. Do I really need the entire phase information on my detected IM-signal when I just need to separate it into inphase and quadrature component which can easily be done by performing a multiplication with sin or cos and filtering it with a lowpass-filter? I understand that coherent detection is neccessary for applications like DPSK but for 2D-QAM IM/DD should just be fine, shouldn‘t it? Looking at literature I found a lot of papers stating the use of QAM-Mapping in e.g. OFDM-applications while using direct detection. Am I missing a point here? Greetings from Germany! Kind regards Flo

Très beau cours. Merci !

I really like your easily understandable teaching! I have a question though, regarding the error rate conversion: Don't we have to take into account the case of multiple bit errors occurring with a single symbol error? Especially as with orthogonal modulation all symbols are equidistant...

hi Leslie, do you think there is a way to obtain the signal phase information in an all-optical way before the photodetection?

Mam, I want to calculate coupling coefficient between two cores or coupling length of a multicore fiber supporting OAM modes. Is it possible to directly copmpute from COMSOL ? Thanks in advance.

Very well explained and I hate Math too LOL

At 13:00, is it an actual physical filter? or is it just modeling the lowpass gain-bandwidth product of a TIA? Thanks

Great channel Pr Rusch

This video is a very straightforward explanation without intimidating mathematical equations.

Merci !!!!

I just found your channel and I really appreciate all the work you put into these. Excellent instruction!

Thanks a lot for clearing my doubts !

So just to be clear, after the serial to parallel conversion (see 15:29) we do quadrature amplitude modulation but this is NOT actually modulation in the traditional sense of circuitry to modulate? It's more of a mapping, correct? Also, to physically transmit the signal do we have to use the same modulation scheme as the one used in the "mapping" stage?

good

Amazing! Thank you very much

Nice

Thanks Mam, very effective lectures in the whole playplist, I am following it to revise the whole course

Thanks Professor

thank you very much

merci beaucoup

merci madame pour ce contenu

omg, finally i get it, thanks!

Thank you so much Professor for uploading videos about CMA! Before this, I couldn't find any content on CMA on KZbin. Your efforts are greatly appreciated. Could you please consider making a video explaining the mathematics behind CMA? That would be really helpful. Thanks again!

Hi, thank you for awesome video. At 10:27, the fractions inside of Q functions for P_e of BPSK and BFSK looks the same at the end. I think there is a typo for BPSK case.

Great Job! Congrat!

great video

I've been in the business for many years, your teaching methods are awesome.

the link was invalid in the end of the video . Could you please update the link?

Dear Professor, thank you for this detailed explanation. I have 3 questions and would be grateful to get responses from you or recommendations for what to read. 1. Is the modulation at the subcarrier level not actual modulation in the sense of varying some aspect of a wave (phase, amplitude, frequency, etc) to embed information? Is it simply a mapping between data bits and our choice of points on the constellation diagram? 2. From the IFFT module we get complex numbers e.g. a +bi. If we use 64 subcarriers, I understand that we would get 64 time samples i.e. 64 different complex numbers. Now how are these 64 complex numbers combined to form a single symbol to be sent? 3. For the actual transmission, does a (real part) modulate the cosine while b ('imaginary') part modulate the sine? in other words, what is the physical process for going from the complex time samples into physical voltage variations that results in RF emissions. The 5GHz oscillator you mention going to be split into one cosine and another sine (90 degrees out of phase), have these individually modulated and then the modulated sine is combined with the modulated cosine before finally being used to induce voltage changes at the antenna feedpoint..? Merci

I can never thank you enough for uploading your lectures on the public platform for free, they are truly a goldmine. I was failing to understand communication system since first year at varsity, but through watching your lectures im happy and grateful for the comm. systems intuition and understanding that i have gained.

merci madame

This is the explanation I’ve been looking🙌🏾

Best explanation, your lectures are top notch

it is very useful explanation, thank you very much

Thanks for the illustration! But seems that the last four minutes of the video is all black has no audio

Much Appreciated Professor.

I think it's backwards at 9:46. Ergodic is always stationary but not vice versa. Iaian Explains Signals has a nice video showing this.

This is an amazing video! Finally I understand this topic!

I need an English translation to Arabic please ❤

Thank you for these videos. You’re awesome!

Hmm nice try but things are quite complicated then what is presented...but this lays out a very good foundation

Perfect!

x(t)*delta(t-tau) = x(tau) Isn't it?

Mam, with your explanations anyone can master the book by Sklar. Is there a place where each page of the book is discussed via a video like it is done here !!

Hey I just wanted to say that, as a network engineer who is trying to learn more about RF without getting neck deep into math and physics, this video was amazing! You explained it in a very approachable way that sitll had a great depth of information.

Mam, you are so good that I am watching all video even when I am not enrolled 😇🤩 Many Many Many ... Thanks for sharing your knowledge.

you are no less than God .... many many thanks yr teachings . All your videos make an excellent resource for students.

Thank you so much

Thanks a lot Prof. Leslie; Please, I have very interesting question, I'll so appreciative to you if you have precise answer for it, the question is about how we can theoretically calculate the cut of frequency of the raised cosine filter for OFDM signal (pulse shaping) before driving the IQ modulator for frequency upconversion from baseband to RF carrier? Please, I'm so need your help about that from your experience and deep knowledge in this regard. thank a lot :)