Instructions
Place the wireless router that broadcasts the signal you connect to on a desk, counter or nightstand on the same floor that you play the DSi on, preferably in a location where the signal must pass through fewer walls. Wireless broadcast points provide the strongest signals if on the same vertical level as the connecting component. Walls reduce the strength of the Wi-Fi signal.
Turn off devices that can interfere with the wireless broadcast signal. These are any devices that emit a radio frequency, including microwave ovens, baby monitors, cordless phones and even fluorescent lights.
Move nearer to the wireless access point when playing the DSi. This may eliminate anything that may be reducing the signal strength of the wireless broadcast.