Instructions
Place your wireless router somewhere other than your floor and away from walls. Keep metal objects away from your router, as these can affect the router's wireless performance. An improved wireless router range means you can game on your PSP further away from it.
Play with as few walls between you and your remote-play partner as possible. Each wall your wireless signal has to travel through will degrade it, lowering the distance you can be apart. The maximum range for a wireless connection is around 100 feet without interference.
Download PSP System Software updates. These software updates can provide fixes and improvements to the PSP's hardware, including the wireless radio, that could improve the system's wireless range. Because of differences in PSP models, you'll need to consult your user's manual for instructions on system software updates.