adding noise to y = a sin(w*t)

[khan;;;;;;;;;;;;;;;;]

i generated a signal y=a*sin(w*t) on time domian ( here time is varying)

now i want to add noise to y i.e y1=y+ % of amplitude of noise * y

to solve this i did like this but i dont know whether it is correct or not

can give me a solution or hint.......

[khan;;;;;;;;;;;;;;;;]

hi sir plz tell me whether iam going in correct way or not.......

[altenbach]

• Why are you dividing the noise by 10? That does not give you percentage. It should probably be a fraction of the amplitude.
• Gaussian white noise is probably more realistic than uniform white noise.

[khan;;;;;;;;;;;;;;;;]

thanq for ur reply sir

sir by mistake i wrote 10 its ok 

but after filtering iam getting exact value of amplitude but not phase

how can i get both amplitude and phase exactly after filtering (amp n phase should match to input values after filtering)

plz reply me.......

[altenbach]

Filtering causes a phase shift. Maybe this old discussion will give you some ideas.

[Coq_Rouge]

Why do you want zero phase. Unless this is specified in your assignment. I would not think about it. As it is inherent part of IIR filtering. But I am surprised that you teacher allow the extensive use of Express VIs.

[khan;;;;;;;;;;;;;;;;]

sir my problem is explaining here..........

let i havegenerated a sinsignal having amplitude, frequency and phase

after filetring iam getting correct amplitude

but phase is changing. i want exact phase as we given...........

how can i achieve this sir plz reoly me..........

if u want i can post my vi.....

[khan;;;;;;;;;;;;;;;;]

no sir my teacher didn't allow me to use this

just i find that this is easiest way thats way i am using express VIs

[sumit.sen]

Whenever a signal is passed through a filter, there is some phase delay introduced by the filter. For a better picture, you can analyze the phase response of the filter.

[khan;;;;;;;;;;;;;;;;]

k thanq sir

sir small doubt

To simulate a sine wave just i have used simulate express vi n added noise because option is there (is this correct procedure to simulate a sin)

n if i use control n simulation loop how can i add noise to sin signal function