Radio reception apparatus, radio transmission apparatus, and radio communication method

摘要

Where first and second reference signals for a first and second communication system, respectively, are transmitted, resources that affect a reception apparatus compatible only with the first communication system can be minimized, and the throughput can be prevented from being deteriorated. As resources for a reference signal CSI-RS for LTE-A, last half symbols in a time direction of a resource unit RB/Sub-frame defined in a frequency-time domain are used, and the CSI-RS is allocated in a position up to the last two symbols or in the last symbol, or the like, of a particular RB/Sub-frame and transmitted when a reference signal 4RS for LTE is transmitted to a reception apparatus in addition to transmitting CSI-RS for LTE-A. The reception apparatus receives CSI-RS allocated in the last half symbol of RB/Sub-frame based on CSI-RS allocation information, measures channel quality by using this CSI-RS, and transmits and reports feedback information.

主权项

1. An integrated circuit to controlling a process, the process comprising:
receiving, in at least one mode of operation, a first reference signal for a first communication system, the first reference signal being mapped in a plurality of symbols of both a former half and a latter half, and the plurality of symbols being divided in the former half and the latter half according to a time direction, of which a subframe is comprised; receiving, in the at least one mode of operation, a second reference signal for a second communication system, the second reference signal being mapped to only a last two symbols in the latter half of symbols; and calculating channel quality information using at least the second reference signal, wherein the first reference signal is a Long Term Evolution (LTE) reference signal and the second reference signal is an LTE-Advanced reference signal.