如何使用 google-analytics 和 php 跟踪下载页面?

I have a download page in php that after performing some checks returns a file, without displaying any html:

header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename=xyz.exe');
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
header('Content-Length: ' . filesize(LOCAL_FILE));
readfile(LOCAL_FILE);

现在我想用 google-analytics 跟踪这个页面.在不显示 html 的情况下实现这一目标的最佳方法是什么?