autocomplete ui datasource

autocomplete ui datasource

I am trying to get an autocomplete text field using remote data retrieved by a php file.  On the demo for the autocomplete ui the use the file search.php  -  I  would like to see what search.php should look like to retrieve my data.  I am currently pulling valid json data into a variable named $response, but I must have something out of place.  If there anyone that can give me and example of what that file should look like.
 
Thanks,
Allen