De-noising an accelerometer with autoregression

[ramesses]

Hi
I want to ask about denoising accelerometre with autoregression after filtring high frequency noise. I analysed the noise with Burg method.
To denoise the signal, I made a simulation with autoregression and subtracted it from the noised signal.
Now, I have a problem. The std of the signale become bigger.

What does it mean ? or this is a wrong way to denoise a signal ?

 

[olivermsun]

It's a tough problem. Can you show an example graph or something like that?

 

[ramesses]

I'm not sure that I applied correctly the filter.

do I have to simulate the process the auto-regression, then subtract the simulation for the original signal.

or use the transfer function like that : Y(n) =S(n)*1/(1+Σ_iα_n-iY(n-i)) , where S(n) is the original signal ?

Sorry, I'm not very familiar with signal processing