A base station apparatus configured to communicate with a terminal apparatus, the base station apparatus comprising: a transmitting unit configured to transmit an enhanced physical downlink control channel using one or several enhanced control channel elements included in a resource block set corresponding to a plurality of resource block pairs, the enhanced physical downlink control channel being transmitted using either localized transmission or distributed transmission, wherein each of the plurality of resource block pairs includes a specific number of enhanced resource element groups, first resource elements except second resource elements carrying demodulation reference signal in each of the plurality of resource block pairs are numbered, each of the specific number of enhanced resource element groups is constituted of third resource elements with a same number in each of the plurality of resource block pairs, the third resource elements being a part of the first resource elements, each of the one or several enhanced control channel elements consists of a plurality of enhanced resource element groups, for the localized transmission each of the one or several enhanced control channel elements corresponds to first enhanced resource element groups, the first enhanced resource element groups being in a resource block pair among the plurality of resource block pairs, for the distributed transmission each of the one or several enhanced control channel elements corresponds to second enhanced resource element groups, the second enhanced resource element groups being in a plurality of resource block pairs among the plurality of resource block pairs, and a first set of combinations and a second set of combinations are the same, a first combination for the localized transmission being one of the first set, a second combination for the distributed transmission being one of the second set, the first and the second sets including combinations of numbers of enhanced resource element groups corresponding to each of the one or several enhanced control channel elements. a transmitting unit configured to transmit an enhanced physical downlink control channel using one or several enhanced control channel elements included in a resource block set corresponding to a plurality of resource block pairs, the enhanced physical downlink control channel being transmitted using either localized transmission or distributed transmission, wherein each of the plurality of resource block pairs includes a specific number of enhanced resource element groups, first resource elements except second resource elements carrying demodulation reference signal in each of the plurality of resource block pairs are numbered, each of the specific number of enhanced resource element groups is constituted of third resource elements with a same number in each of the plurality of resource block pairs, the third resource elements being a part of the first resource elements, each of the one or several enhanced control channel elements consists of a plurality of enhanced resource element groups, for the localized transmission each of the one or several enhanced control channel elements corresponds to first enhanced resource element groups, the first enhanced resource element groups being in a resource block pair among the plurality of resource block pairs, for the distributed transmission each of the one or several enhanced control channel elements corresponds to second enhanced resource element groups, the second enhanced resource element groups being in a plurality of resource block pairs among the plurality of resource block pairs, and a first set of combinations and a second set of combinations are the same, a first combination for the localized transmission being one of the first set, a second combination for the distributed transmission being one of the second set, the first and the second sets including combinations of numbers of enhanced resource element groups corresponding to each of the one or several enhanced control channel elements.