The present invention relates to performing properly wireless communications. A communication system includes a first information processing apparatus and a plurality of second information processing apparatuses. The first information processing apparatus is an information processing apparatus that assigns a plurality of channel resources for wireless communications to the plurality of second information processing apparatuses and notify the plurality of second information processing apparatuses of the assignments. The second information processing apparatuses, upon receipt of the notification, transmit to the first information processing apparatus a plurality of signals for providing predetermined information to the first information processing apparatus by using the plurality of assigned channel resources.