Patent ID: 8606304

Claim:
A paging signal transmission method in which a radio base station transmits a paging signal for notification of an incoming call for a mobile station belonging to any one of a plurality of groups, the method comprising the steps of: notifying, from the radio base station to the mobile station, a discontinuous reception interval and a total number of the groups, the discontinuous reception interval representing an interval at which discontinuous reception of the paging signal is performed; determining, at the mobile station, a timing for receiving the paging signal on the basis of the notified discontinuous reception interval and the notified total number of the groups; receiving, at the mobile station, the paging signal transmitted from the radio base station, at the determined timing; and performing, at the mobile station, incoming call processing, when the received paging signal is a paging signal addressed to the mobile station, wherein the reception timing determining unit is configured to determine that the timing is a subframe which is selected from among a plurality of subframes forming a radio frame to which the paging signal is mapped; the paging signal is transmitted only in one subframe in a plurality of radio frames; and the reception timing determining unit is configured to determine that the timing is a predetermined subframe in radio frames specified by SFN calculated from the following formula: G = U ⁢ ⁢ mod ⁢ ⁢ N ⁢ ⁢ S ⁢ ⁢ F ⁢ ⁢ N ⁢ ⁢ mod ⁢ ⁢ T = G · T N [ Formula ⁢ ⁢ 1 ] where “T” represents the number of the radio frames included in the discontinuous reception interval, “N” represents the total number of the groups, “U” represents identification information on the mobile station, “G” represents identification information on the group to which the mobile station belongs, and “T≧N” is satisfied.