Replacing JavaScript functionality with PHP

Hi, I'm rewriting some web pages trying to replace a lot of JavaScript with PHP (before including some mySQL for even more dynamic content); however, I am having a little difficulty in one area... Currently, if a page is displayed in the main window for the site, then a menu is displayed on the left (where else); however, if the same page is displayed in a popup window, then the menu is suppressed. This works because, the site launches all popup windows with the same name, 'popupWin', so I can use if (self.name == 'popupWin')... in the JavaScript to suppress the menu. The HTML for the menu is built dynamically by the JavaScript. I can't see how PHP (on the server) will know about the browser window name, so is there a way to reproduce this functionality in PHP? I'm new to PHP, so apologies if this is a time-waster. I spent quite a while looking through the archives, but... well needles and haystacks! Thanks, Richard