MATLAB: How to resample a signal by a fraction

resampling

Hello,

I have the time-domain received signal v(t) and I want to re-sample it at as v(t/(1+a)), where a is not an integer and it is in the order of ~10^-3. How can I do that in MATLAB, since the resample function requires that both P and Q be integer?

Thanks

Best Answer

You could use interpolation instead. Something like this:

vnew = interp1( t, v, t/(1+a), 'linear');

You could use other interpolation approaches ('spline','cubic', etc.) as well, as appropriate.

Related Solutions

MATLAB: How to display a matrix which has elements with big difference in values

format longg
doc format

MATLAB: How to make 2 data sets the same size

Have a look at the resample function;

>> help resample
 resample  Change the sampling rate of a signal.
    Y = resample(X,P,Q) resamples the sequence in vector X at P/Q times
    the original sample rate using a polyphase implementation.  Y is P/Q 
    times the length of X (or the ceiling of this if P/Q is not an integer).  
    P and Q must be positive integers.

For example you would be looking at;

time_a = linspace(1,10,900);
time_t = linspace(1,10,6000);
temp = rand(size(time_t))
absorb = rand(size(time_a));
temp_undersampled = resample(temp, length(absorb), length(temp));
size(temp_undersampled)

This is a pretty rough example, and if you want to go the other way, there's interp1 (that's a 1 not an ell) - but the usual caveats apply with interpolation.

Best Answer

Related Solutions

MATLAB: How to display a matrix which has elements with big difference in values

MATLAB: How to make 2 data sets the same size

Related Question