'modele depose' is just french for 'registered trademark' or something similar.
i guess that tells you the bike is french.. maybe gitane or motobecane.
hard to tell anything without any markings...

browse through the fixed gear gallery http://www.fixedgeargallery.com/ (not necessarily because it's fixed gear but more because there are lots of pics of older frames there) and see if you can find a french bike that looks like yours...

other than that, i don't know.