Radio base station and mobile communication method

Abstract

A radio base station (eNB) according to the present invention includes: a first reception unit (11) configured to receive a preamble from a mobile station (UE); a response transmission unit (12) configured to transmit, to the mobile station (UE), a response to the preamble; and a second reception unit (13A) configured to determine a degree of congestion in a cell, and to receive, from the mobile station (UE), an uplink signal transmitted in response to a first control signal included in the response, wherein the second reception unit (13A) is configured to determine whether or not to discard the uplink signal, depending on whether or not the preamble is an initial connection preamble for performing an initial connection, when it is determined that the degree of congestion in the cell is high.

Dependencies are inferred from the claim text.