Provided is a mobile station UE equipped with a broadcast information generation unit (11) which generates broadcast information containing tag information formed by a plurality of bits. The tag information has a value defined only by a plurality of first bit values or by a plurality of first bit values and second bit values. The first bits contain a flag indicating whether the tag information contains the second bits. The broadcast information generation unit (11) updates the tag information value each time the content of the broadcast information is updated.