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In Reply to: RE: reading materials posted by ahendler on June 03, 2014 at 17:52:42
This is probably not what you want, but if you really want to understand what's going on, this is where I started. I learned digital signal processing from a 1975 book, "Digital Signal Processing" by Oppenheim and Schafer. The latest version of this book is called "Discrete Time Signal Processing" and is linked below.
This may not be the easiest book on the market and some of the reviews suggest it is at the graduate level. This was OK for me, as I was a math major. It took a while to work through this book, but after doing so then I was able to read more specialized technical books and articles and complete the project that I was working on, having developed the confidence that I understood what I was doing rather then just memorizing formulas and recipes.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Follow Ups:
The 2nd edition is a lot cheaper!
Thanks Tony,
I've read some of Oppenheim and Schafer as it was sort of the bible and we had one at work. The book that I really started with was Hamming's digital filters. Killed a vacation's evenings with that one. I am anything but an expert but have managed to "do what needed to be done" for my projects. Wow, this is a way-back machine post. Later one of them had a floating point FIR in 6805 assembly... I'd blissfully forgotten.
Obviously what passes for my "understanding" of DSD is uselessly vague, I thought it was just PDM. I've never done anything with it so vague's been adequate but I posed my question out of mild curiosity to know if there was more to it. Sounds like there is...
Thanks for the advice, I appreciate not just being told to consult Wikiwhatever..
Rick
I've not had to design any filters, digital or analog, so I haven't studied Hamming's book. I didn't find "Digital Signal Processing" to be as difficult as Wozencraft and Jacob's, "Principles of Communications Engineering".
Back in the early 1980's DEC had been doing a project to put 10 Mbps Ethernet over cable television networks, as General Motors had wired their factories up with video cable and amplifiers. We didn't have any RF modem design capability so we contracted this out. As DEC's Chief Network Architect I had to interact with these engineers and make sure they understood how the Ethernet really worked. They were always talking about various error detecting and correcting codes and bit error rates for various types of modulation as a function of signal to noise ratio. I was familiar with these codes, but not communications theory . I knew that my lack of knowledge would come out sooner or later and I really needed some way to convince myself that these people knew what they were doing, so the only way to deal with the situation was to learn communications theory.
I admitted my ignorance and asked the lead engineer for a good book to study, and he told me to read, "Principles of Communications Engineering." This ate up my evenings for several months. I was able to get through all the chapters that I needed and even got though the chapter on FM modulation and how it works to increase signal to noise ratio at the expense of bandwidth utilization. Later I found out from the junior engineer that his boss had been busting my balls by giving me that book, as there were easier books to read that weren't so heavy on math.
I don't believe there are any textbooks or even research articles that get down and dirty into the messy part of DSD, how sigma-delta modulators actually work (or as some say, don't work). The published articles that I've seen makes all kinds of linearizing assumptions and then admit that things are really more complex, for example the existence of limit cycles and unstable operation (potential lockup) at high levels. (You will find a reference to lockup in the Weiss Saracon user manual.) There is a theory of dither that describes how quantization distortion can be decorrelated from signal and how noise shaping can work for multiple-bit formats but it's a PhD thesis and uses advanced probability theory and calculus.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
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