working of Recursive least square method with an example

Hello,

I want to apply recursive least square filtering technique for a signal interrupted with noise induced due to the motion artifacts.I found this

Recursive least square fitlering

on the file exchange but this is bit hard to understand.Could some one explain this recursive least square filtering with an example.

Thanks in advance.

Answer 1

[Image Analyst]

I bet the author could. Did you ask him? Why do you think this is the way to go instead of something simpler like the wiener filter to fix the non-delta-function point spread function?

[Gova ReDDy]

Hello Image Analyst,

I mailed him but no reply yet.I am working wuth the Pulse oximetry project where I am extracting and analysing the output pulse signals.The Pulse signals are sometimes induced with noise from the movements of the subjects( called motion artifacts) and will be different from the original pulse.So, I need to remove these motion artifacts. Some of the papers mentioned the Recursive least square fitlering as the solution but I am confused with this implentation.Is there any other solution for removing the motion artifacts? Thanks in Advance.

[Gova ReDDy]

Is there anyother methods or solutions for this?

[Image Analyst]

Like I suggested, wiener filter, for which there's a function in MATLAB for. Not sure it if it's in a toolbox or not.

[Image Analyst]

But there already examples in the help and on the website for wiener and wiener2 - why do I need to reproduce them here for you?

[Gova ReDDy]

Image Analyst, Can you please explain me why you are not responding to me.Is there anything wrong from my side.Thankyou.

[Image Analyst]

But it looks like I did respond - on Sept. 23rd, 24th, and 26th. So why are you saying that I didn't respond. I doubt I made two responses twice in a row so I think you made a comment between my last two and have since deleted it. From the looks of my last comment, it looks like you were asking for example code on wiener and wiener2 and I referred you to the examples in the help documentation for them. Now I don't have any wiener demos written up already for you, so if I were to do one I'd have to make up one custom for you and I'd start with the example code in the help. This is basically the same process you could do yourself - you don't need me for that. Sometimes I simply don't have the time to create new customized demos for people - I hope you understand.

After 3 months I think you can assume no one is going to be writing the demo for you, so why don't you get started on some sample code and post it and ask people your questions about why it doesn't work?

[Gova ReDDy]

Hi IA thanks for the reply,

Basically I am working with the pusleMeter project where the pulse signals from the analog baord (I designed) will be effected when the subject finger is moving then the pulse signals will be induced with the motion artifacts (I guess it is similar to the ECG motion artifacts). I read some papers in which they say adpative filteirng using Recursive least Mean square will remove the motion artifacts.

So,I am planning to follow the adaptive filtering of Recursive least mean square and implemented was getting error so I posted this new one Error with the RLS filtering.

If you have time can you please look over it and suggest me the right way of implementation. Thanks.

[Gova ReDDy]

Hi Image analyst could please help me out in solving the error because I ended up here and unable to move forward.

[Image Analyst]

Sorry - I don't know signal processing that well.