power spectrum estimation in wavenumber domain

Hi everyone, I am trying to estimate the power spectrum in space domain using pburg. But when I got my spectrum its gives me Inverted results. I am not able to understand the problem. Can anyone please suggest me, where could be the problem. My procedure is as: a=load('data.dat') length of data =95; order=4; si=2.5; [Pxx,w]=pburg(detrend(a),4,128) b=log(Pxx); plot(w,b)

thanks

Answer 1

[juntian chen]

I'm seeking the answer, too