Where is your wireless router located? If its fairly close and you still get poor signal, you could have interference on the wireless signal. Some things to try: Change the wireless channel setting on your router, don't use AUTO. Choose channel 1, 6, or 11.
Do you have a cordless landline phone? Do not place it too close to the router or that is a factor in the interference.
You may not even need another device as that may add to your problems.
Series 2 (PLS, sold)
TiVo HD 1TB (157 HD Hrs, PLS, "652")
Roamio! Oh, wait, Its Juliet!
OTA! OTA! OTA!
The TiVo Apocalypse begins on Sat 2013 Feb 16 00:00 GMT!