How to calculate PSD estimate of acoustic data in 1Hz bins? pwelch?

Hi everyone,

I have several files of 118.5 second duration that I would like to calculate the PSD of. I want to do this in 1Hz frequency bins, with Hanning window and 50% overlap, and have considered using pwelch.

First I calibrate the data and then have tried to work out how to use pwelch to no avail so far:

path=('C:\Users\datafolder');

d=dir(fullfile(path, '*.wav')); %list all .wav files in path folder

files=length(d); %number of files in folder

for i=1:files    %for each file
    disp(d(i).name);
    filename=fullfile(path, d(i).name); %get full filename
    [xbit, fs]=audioread(filename); %and then sampled data and sampling 
                                    %freq (fs) from audioread function
    cal=-176.2; 
    cal=power(10, cal/20); %calibration correction factor
    calxbit=xbit*cal; %apply calibration
end


[pxx,f]=pwelch(calxbit, window, 0.5, [], 144e3);

How do I specify that I want to use 1Hz bins? My data is sampled at 144kHz.

Thanks!!