A wireless base station, includes: a wireless transceiver configured to transmit to a wireless terminal a downlink frame including a downlink control information, the wireless downlink control information includes information representing a specified offset, wherein the wireless transceiver is further configured to receive an uplink frame from the wireless terminal; and a processor circuit coupled to the wireless transceiver and configured to determine uplink control information from the uplink frame, the uplink control information being offset by at least the specified offset from a location in the uplink frame that is the same as a location where the downlink control information was located in the downlink frame.