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This is one of the domains where I really regret not caring about math and not furthering my education. I've tried to get into communication theory to work on

This is one of the domains where I really regret not caring about math and not furthering my education. I've tried to get into communication theory to work on some moderately complex SDR projects, but it seems I cant escape math for this.

newhouseb 6y ago
There are some ham radio folks who put together really great videos for building an intuition on all sorts of electrical engineering / signal processing topics that require minimal math. For I/Q signals in particular, W2AEW has a couple great videos that explain the intuition and then demonstrate things in action on real instruments: - https://www.youtube.com/watch?v=h_7d-m1ehoY https://www.youtube.com/watch?v=h_7d-m1ehoY - https://www.youtube.com/watch?v=5GGD99Qi1PA https://www.youtube.com/watch?v=5GGD99Qi1PA
cycomanic 6y ago
The thing is this is all really not complicated, but unfortunately the way we (at least I) are being taught complex numbers is terrible. They essentially fall out of thin air without much explanation and sure the concept as a mathematical construct is easy enough to understand, but that doesn't really explain the why and the elegance of what you can do with them. I really only understood this when I started doing communications (and that was after doing a PhD in physics mind you).
- vvanders 6y ago
  Yeah, you can actually simulate a good chunk of this with just trig, I actually simulated a mixer[1] in python and was able to work out how I/Q got mixed into the baseband, it was a ton of fun. Once you've got the data in I/Q lots of the modulation modes just fall out really easily(I recommend reading about AM, FM and BPSK/QPSK as a starting point which then you can generalize into QAM). [1] https://en.wikipedia.org/wiki/Frequency_mixer#Diode https://en.wikipedia.org/wiki/Frequency_mixer#Diode
mhh__ 6y ago
There is math, sure, but you could treat it as a target to work towards. You really just need calculus for DSP work to start with. Remember that it's very easy to use Python or Matlab to check your answers My only concrete advise is to avoid the Proakis book
mikewarot 6y ago
Good news, you don't really have to do the math to get an intuition of what's going on... which will likely get you through it. Try out GNU Radio... you can just use your audio I/O instead of messing with RF, etc. Build a few graphs where you use complex signals, multiply them together, etc... and you can get the hang of it, for no $$ and only a few hours time.

newhouseb 6y ago

There are some ham radio folks who put together really great videos for building an intuition on all sorts of electrical engineering / signal processing topics that require minimal math. For I/Q signals in particular, W2AEW has a couple great videos that explain the intuition and then demonstrate things in action on real instruments: - https://www.youtube.com/watch?v=h_7d-m1ehoY https://www.youtube.com/watch?v=h_7d-m1ehoY - https://www.youtube.com/watch?v=5GGD99Qi1PA https://www.youtube.com/watch?v=5GGD99Qi1PA

cycomanic 6y ago

The thing is this is all really not complicated, but unfortunately the way we (at least I) are being taught complex numbers is terrible. They essentially fall out of thin air without much explanation and sure the concept as a mathematical construct is easy enough to understand, but that doesn't really explain the why and the elegance of what you can do with them. I really only understood this when I started doing communications (and that was after doing a PhD in physics mind you).

vvanders 6y ago
Yeah, you can actually simulate a good chunk of this with just trig, I actually simulated a mixer[1] in python and was able to work out how I/Q got mixed into the baseband, it was a ton of fun. Once you've got the data in I/Q lots of the modulation modes just fall out really easily(I recommend reading about AM, FM and BPSK/QPSK as a starting point which then you can generalize into QAM). [1] https://en.wikipedia.org/wiki/Frequency_mixer#Diode https://en.wikipedia.org/wiki/Frequency_mixer#Diode

mhh__ 6y ago

There is math, sure, but you could treat it as a target to work towards. You really just need calculus for DSP work to start with. Remember that it's very easy to use Python or Matlab to check your answers My only concrete advise is to avoid the Proakis book

mikewarot 6y ago

Good news, you don't really have to do the math to get an intuition of what's going on... which will likely get you through it. Try out GNU Radio... you can just use your audio I/O instead of messing with RF, etc. Build a few graphs where you use complex signals, multiply them together, etc... and you can get the hang of it, for no $$ and only a few hours time.