Curve Fitting for FFT plot

Hi all,

I have data from accelerometer(time domain) and convert it to fft. Below is my coding and the plot.

%Clear clc;

%For Sampling Rate 512

c= Ch_512_60mss'; Track2=c(1,1:4096); Track1_X_Resolution=(1/512); Fs = (1/Track1_X_Resolution); L=4096;%16385;

% Sampling frequency t =(0:L-1)*1/Fs;% 0:1/Fs:2;

x = Track2; nfft = 2^nextpow2(L); % Next power of 2 from length of y

% Length of FFT % Take fft, padding with ze X = fft(x,nfft); X = X(1:nfft/2);

% Take the magnitude of fft of x mx = abs(X);

% Frequency vector f = (0:nfft/2-1)*Fs/nfft; % f1=fit(t,f,'fourier8');

% Generate the plot figure(1); plot(t,x); title('Sine Wave Signal'); xlabel('Time (s)'); ylabel('Amplitude'); figure(2); plot(f,mx); title('Power Spectrum of a Sine Wave'); xlabel('Frequency(Hz)'); ylabel('Power');

However I need to do the curve fit to the plot. Can somebody share with me the coding.I don't know how to do it.

Thanks a lot.

[arun]

Fitting only "one curve" for this random data may spoil ur upcoming analysis. U shall try piecewise fit even shat is not good for noisy data.