| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a communication system in which a subcarrier to transmit uplink data to a base station is allocated to a user device. <P>SOLUTION: ACK/NACK messages for data transmitted on the uplink are then transmitted by a base station on subcarriers that depend on the subcarriers used to carry the uplink data. A direct mapping function is preferably used to determine the subcarriers to be used for the ACK/NACK messages from the uplink subcarriers. In another embodiment, the ACK/NACK messages are transmitted to the user devices on subcarriers that are previously identified to the user devices, preferably by transmitting one or more index values to the user device in a control channel thereof. <P>COPYRIGHT: (C)2011,JPO&INPIT |
