c1910 wrote: ...>>>>> using Hilbert Trans >>>>> if : A = amplitude of carrier >>>>> >>>>> w = freq of carrier >>>>> >>>>> m(t)= information signal >>>>> >>>>> I = A*cos(wt)*m(t) >>>>> Q = A*sin(wt)*m(t) >>>>> >>>>> I^2 + Q^2 = A^2*cos^2(wt)*m(t)^2 + A^2*sin^2(wt)*m(t)^2 >>>>> = A^2*m(t)^2*[cos^2(wt) + sin^2(wt)] = A^2*m(t)^2*1 = A^2*m(t)^2 >>>>> >>>>> sqrt(A^2*m(t)^2) = A*m(t)...this is the envelope right? >>>> Yes....>> If the sample rate is high relative to the carrier frequency -- What a >> waste! -- then some of the samples will be close enough to the peak for >> a detector to work is you just average all the absolute values. In a >> simulation, you can adjust all these variables to suit the demo, but in >> real live, you don't have that luxury....> ooo > > ic...How do integrated circuits come into this?> it's too late to change my method... > but it's work... > hehe...thanks for the input...So in your school, it's better to do it wrong than do it late? What school is that? I'm sure many would like to know.> so, there is no explanation in math about hilbert T. if we use it for > discrete signal?I explained it to you. You repeated the proof above. Did you forget it, or did you not understand what you were writing? Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Advantages of Envelope detector using Hilbert Transform
Started by ●February 11, 2008
Reply by ●February 25, 20082008-02-25
Reply by ●February 26, 20082008-02-26
>c1910 wrote: > > ... > >>>>>> using Hilbert Trans >>>>>> if : A = amplitude of carrier >>>>>> >>>>>> w = freq of carrier >>>>>> >>>>>> m(t)= information signal >>>>>> >>>>>> I = A*cos(wt)*m(t) >>>>>> Q = A*sin(wt)*m(t) >>>>>> >>>>>> I^2 + Q^2 = A^2*cos^2(wt)*m(t)^2 + A^2*sin^2(wt)*m(t)^2 >>>>>> = A^2*m(t)^2*[cos^2(wt) + sin^2(wt)] = A^2*m(t)^2*1 = A^2*m(t)^2 >>>>>> >>>>>> sqrt(A^2*m(t)^2) = A*m(t)...this is the envelope right? >>>>> Yes. > > ... > >>> If the sample rate is high relative to the carrier frequency -- What a>>> waste! -- then some of the samples will be close enough to the peakfor>>> a detector to work is you just average all the absolute values. In a>>> simulation, you can adjust all these variables to suit the demo, butin>>> real live, you don't have that luxury. > > ... > >> ooo >> >> ic... > >How do integrated circuits come into this? > >> it's too late to change my method... >> but it's work... >> hehe...thanks for the input... > >So in your school, it's better to do it wrong than do it late? What >school is that? I'm sure many would like to know. > >> so, there is no explanation in math about hilbert T. if we use it for >> discrete signal? > >I explained it to you. You repeated the proof above. Did you forget it, >or did you not understand what you were writing? > >Jerry >-- >Engineering is the art of making what you want from things you can get. >����������������������������������������������������������������������� >i think my method doesn't fully wrong... it's just different from the original one... as long as the hilbert T. is cover the uncover peak of the signal... and it does work well... the proof, i have is in continues signal... i don't have the proof in discrete signal... and the proof in continues signal, i think it is the same when we use square law...
