If not otherwise stated in device specifications, Nokia Symbian^3 devices use the 2.4 GHz band with 802.11n WLAN connections (same band as with 802.11b and 802.11g connections). The 5 GHz band is not supported.
The 2.4 GHz band is used e.g. with Nokia N8-00, C6-01, C7-00, E7-00. X7-00, E6-00 devices.