Your phone and your network (Wi-Fi) could interfere with each other if they are both operating on the same frequency of 5.8GHz, but you are still in luck. Devices that operate at 5.8GHz typically enjoy a lot more room rather than devices that operate at 2.4GHz. This is because 802.11a networking gear, which uses the 5.8GHz band, has eight nonoverlapping channels to choose from for indoor use.
In contrast, 2.4GHz 802.11g devices have only three nonoverlapping channels. The extra room in the 5.8GHz band makes it much more easier to keep devices operating at that frequency with out interfering each other's. The trick is to use separate nonoverlapping channels for your network and for your mobile phone. Check the user manual for your wireless router or access point for instructions on how to adjust the channel of your wireless network.