Patent ID: 8705414

Claim:
A method for receiving ACK (ACKnowledgement)/NACK (Negative-ACKnowledgement) at a Base Station (BS) in a wireless communication system, the method comprising: transmitting the data to a Mobile Station (MS) through a first subframe of a Time Division Duplex (TDD) frame, wherein the TDD frame includes one or more subframes used for Hybrid-Automatic Repeat reQuest (HARQ) processing and one or more subframes not used for the HARQ processing; and receiving the ACK/NACK for the data from the MS through a second subframe of a TDD frame #i, wherein uplink subframes used for the HARQ processing in the TDD frame #i are mapped to logical uplink subframes of a logical frame, wherein downlink subframes corresponding to the uplink subframes are mapped to logical downlink subframes of the logical frame, and wherein a logical uplink subframe index n UL corresponding to a second subframe in the logical frame is determined by the following equation A: n UL = ⌊ n DL / ⁢ ⌈ N DL N UL ⌉ ⌋ [ Equation ⁢ ⁢ A ] wherein n DL is a logical downlink subframe index corresponding to a first subframe in the logical frame, N DL is a number of downlink subframes used for the HARQ processing in the TDD frame, N UL is a number of uplink subframes used for the HARQ processing in the TDD frame, └ ┘ is a floor function, and ┌ ┐ is a ceiling function.