Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!know!sdd.hp.com!hplabs!hpcc05!hp-ptp!davew From: davew@hp-ptp.HP.COM (Dave_Waller) Newsgroups: sci.electronics Subject: Re: Orthogonality in general Message-ID: <1920001@hp-ptp.HP.COM> Date: 9 Oct 90 21:08:28 GMT References: <675@paladin.Owego.NY.US> Organization: HP Pacific Technology Park - Sunnyvale, Ca. Lines: 36 nick@paladin.Owego.NY.US (Carmine Nicoletta) writes: > In signal detection of M-ary signals, there is often the need to obtain > orthonormal basis vector sets. There are many suitable choices, the most > ovious are sin(x) and cos(x). But there are also Legendre functions, Hermite > functions, and Bessel functions. > For a finite set of signals, s1(t), s2(t),.... sm(t) defined on some interval, > an orthonormal basis for the signal space can be obtained by using the > Gram-Schmidt procedure. This is a very straight forward procedure discussed > in many Linear Algebra texts. > My problem is this: how does this procedure relate to frequency response of > filters. For example, how does one come up with an N set of filters whose > frequency responses are orthogonal to each other. The answer to this is obvious. Frequency response in this situation is described by the Putz-Schmuckmann function, integrated over the frequency domain for time-invariancy. With this result, the time domain representation of a filter can be convoluted using semiharmonic imaginary logs, resulting in a homogenous well-behaved function that is linear over a range suitable to your problem. Or, you can hook up a resistor and a cap and wing it. Oh yeah, :-) :-) :-) :-) :-) Thanks for reminding me, Carmine, how much I've forgotten since school. The above blathering is for entertainment purposes only. Dave Waller \ The opinions expressed are solely my own, and in no way Hewlett-Packard Co. \ represent those of my employer (but we all know dave@hpdstma.ptp.hp.com | hplabs!hpdstma!dave \ they should!)