Filter coefficient calculation In Sigma studio
in [DSP]
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From: Eric Jacobsen on 11 Feb 2010 17:24 On 2/11/2010 1:13 PM, Jerry Avins wrote: > Eric Jacobsen wrote: >> On 2/10/2010 10:11 PM, Jerry Avins wrote: >>> Tim Wescott wrote: >>>> On Wed, 10 Feb 2010 21:46:32 -0500, Jerry Avins wrote: >>>> >>>>> Randy Yates wrote: >>>>>> Jerry Avins <jya(a)ieee.org> writes: >>>>>>> [...] >>>>>>> According to one passage in the Bible, pi is three. >>>>>> Where is that? >>>>> In the old testament, a the descriptions of a vessel in the Temple. >>>>> >>>>> look look look ... >>>>> >>>>> 1 Kings 4:23. "And he made a molten sea, ten cubits from the one >>>>> brim to >>>>> the other: it was round all about, and its height was five cubits: >>>>> and a >>>>> line of thirty cubits did compass it round about." >>>>> >>>>> Jerry >>>> >>>> Clearly written by a fuzzy studies major. >>> >>> Is the Bible the word of God, or is it not? >>> >>> Jerry >> >> http://www.realoldtestament.com/HomePage.html >> >> Also, click on "Covenant" > > Trying to reconcile the world and the Book is a lot of work, especially > as there's more than one version of the Book to reconcile to. How should > Genesis 1:27 (So God created human beings in his own image. In the image > of God he created them; male and female he created them.)* be squared > with Genesis 2:18 (Then the LORD God said, "It is not good for the man > to be alone. I will make a helper who is just right for him.")* followed > by talk about a rib? Fortunately for me, I don't have to. I just don't > care. > > Jerry > ___________________________ > * New Living Translation (©2007) Likewise, but I thought the vid in the link was hilarious. -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com
From: Eric Jacobsen on 11 Feb 2010 17:28 On 2/11/2010 1:41 PM, Michael Plante wrote: > Jerry Avins wrote: >> Tim Wescott wrote: >>> On Wed, 10 Feb 2010 21:46:32 -0500, Jerry Avins wrote: >>> >>>> Randy Yates wrote: >>>>> Jerry Avins<jya(a)ieee.org> writes: >>>>>> [...] >>>>>> According to one passage in the Bible, pi is three. >>>>> Where is that? >>>> In the old testament, a the descriptions of a vessel in the Temple. >>>> >>>> look look look ... >>>> >>>> 1 Kings 4:23. > > No, 1 Kings 7:23. > > >>>> "And he made a molten sea, ten cubits from the one brim to >>>> the other: it was round all about, and its height was five cubits: and > a >>>> line of thirty cubits did compass it round about." >>>> >>>> Jerry > > One of the first few hits when I googled "ten cubits from the one brim" (no > quotes): > > http://home.teleport.com/~salad/4god/pi.htm > > Short version: the measurements are not redundant. One is an interior > measurement, and one is an exterior measurement. That said, there isn't a > "standard cubit" sitting in Jerusalem or something. ;) > > > >>> Clearly written by a fuzzy studies major. >> Is the Bible the word of God, or is it not? > > Inspired, but not dictated word-for-word. Nevertheless, error-free in the > original languages. No, I don't have time to answer every one of these, > nor am I likely to know the answer to every question you can raise, but > Google is your friend. The basic rule for interpretation (predicated on > believing the Bible) is: if ones encounters an apparent contradiction, > his/her interpretation is wrong. Of course, if you don't believe it, you > can interpret it however you want and find all sorts of problems. One could put that stipulation, i.e., "if one encounters an apparent contradiction, his/her interpretation is wrong", about anything written, ever, by anyone, if one wishes to spin it that way. I can make up a religion and put that caveat in there and it instantly becomes irrefutable, so it's an understandable strategy for believers. -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com
From: Tim Wescott on 11 Feb 2010 19:55 On Mon, 08 Feb 2010 22:36:08 -0600, rammya.tv wrote: > hi.... > i'm currently working on Analog Devices Dsp processor ADAU 1701.. > Sigma studio is the software we are now on,in that i have some queries > in the way they calculate filter coefficient. > > - main specification i needed to design a filter 1)Type[LPF,HPF, etc] > 2)frequency > 3)Q > 4)Gain > > eg: > I want a 2nd order LPF with > Frequency= 1000 > Q=0.5 > Gain=1 > > The given below derivation is the one which i got from sigma studio help > window. > > ->ω0 = 2*pi*f0/Fs > ->gainLinear = 10^(gain/20) > > ->Lowpass > > ->Transfer Function > ->H(s)=1/(s^2+(s/Q)+1) > > ->Coefficients > ->alpha = sin(ω0)/(2*Q) > ->a0 = 1 + alpha > ->a1 = -2*cos(ω0) > ->a2 = 1 - alpha > ->b0 = (1 - cos(ω0)) * gainLinear / 2 ->b1 = 1 - cos(ω0) * > gainLinear > ->b2 = (1 - cos(ω0)) * gainLinear / 2 > > > After compiling we'll get coefficients a1,a2,b0,b1,b2 in hex format in > CAPTURE WINDOW of software. > i did manual calculation using the expression provided above and compare > with that of coeffients of software, but it differs. Please help me to > get detail calculation with the specification i given above. > > > We know ω0 = 2*pi*f0/Fs > -what is the value of pi(180 0r 3.14) -ω0 is the angular representation > of requency i think it will be 180 -then in above value of alpha will be > zero always. -it means Q doesnt have any importantce in filter design > -please suggest a good book which describe in detail about filter design > > with regards > rammya Lots of responses. It's not clear that your problem is in constructing the filter or in executing it. A filter whose impulse response is exactly two cycles of a 2kHz sine wave will have a peak just a hair below 2kHz and will have zeros at 0Hz, 1kHz, 3kHz, etc. Try that -- if you can't get it working in your filter execution code, then you can stop trying to figure out the problem in your filter design code. -- www.wescottdesign.com
From: Les Cargill on 11 Feb 2010 20:09 Jerry Avins wrote: > Randy Yates wrote: >> Jerry Avins <jya(a)ieee.org> writes: >>> [...] >>> According to one passage in the Bible, pi is three. >> >> Where is that? > > In the old testament, a the descriptions of a vessel in the Temple. > > look look look ... > > 1 Kings 4:23. "And he made a molten sea, ten cubits from the one brim to > the other: it was round all about, and its height was five cubits: and a > line of thirty cubits did compass it round about." > > Jerry That's just an approximation to one digit... -- Les Cargill
From: Michael Plante on 11 Feb 2010 22:50
Eric wrote: >On 2/11/2010 1:41 PM, Michael Plante wrote: >> The basic rule for interpretation (predicated on >> believing the Bible) is: if ones encounters an apparent contradiction, >> his/her interpretation is wrong. Of course, if you don't believe it, you >> can interpret it however you want and find all sorts of problems. > >One could put that stipulation, i.e., "if one encounters an apparent >contradiction, his/her interpretation is wrong", about anything written, >ever, by anyone, if one wishes to spin it that way. I can make up a >religion and put that caveat in there and it instantly becomes >irrefutable, so it's an understandable strategy for believers. > Agreed. It's merely a claim of self-consistency, something many careful people would claim about their own various viewpoints. More to the point, it's a claim of a consistent world view, inclusive of the entire set of propositions you believe to be true, whether each is taken on the basis of deduction, induction, or irrationality. Given that it's so "expected", maybe it was excessive of me to point it out. But I was surprised to learn there is at least one major religion that claims quite the opposite: text written chronologically later supersedes the earlier text. |