How to export data with end user labelling

chHeader.ch1.Min = -1;
chHeader.ch1.max = 1;
chData.ch1.startTime=[0];
chData.ch1.value=(chHeader.ch1.max-chHeader.ch1.Min).*rand(1,128) + chHeader.ch1.Min;
save
for k=1:10;
    continue ;
    save 
end

    if true
      % code
    end

I tried the above code to generate ten random signal with above code but every time it overwrite the previous result. I need to make ten different outputs at a time , second issue is while saving the output is it possible that it may asked to set name of that output file