the 3com is a wifi router that has to be connected to a main internet connection and then it would distribute the signal and this is the setup your landlord probably have otherwise you would have to connect thru a cable(which you are not). Since your roommate can receive a good signal and you cant might be for the mere fact that his/her hardware is better than yours or you simply need to upgrade your drivers, I faced the same problem with my Thinkpad and I upgraded the software and drivers and everything is fine.
So bottom line you have two solutions:
-Subscribe to an internet connection yourself, and have your won ocnnection in the room.
- Ask the landlord to do something.
- Upgrade your drivers, most decent laptop brands have free monline upgrades.

Let me know how things go.