Patent ID: 9680589
Date: 2017-06-13
CPC Classifications: H04B,H04J,H04L,H04W

Claim:
1. A method of transmitting positive-acknowledgement (ACK)/negative-acknowledgement (NACK) in a time division duplex (TDD)-based wireless communication system in which M (M>2) downlink subframes are associated with an uplink subframe in each of two serving cells, the method performed by a user equipment (UE) and comprising: receiving M downlink subframes associated with an uplink subframe n in each of the two serving cells; and transmitting an ACK/NACK response for the M downlink subframes received in each of the two serving cells by using one resource selected from four candidate resources in the uplink subframe n, wherein the two serving cells comprises a first serving cell and a second serving cell, wherein, in the M downlink subframes received in the first serving cell, if a physical downlink shared channel (PDSCH) indicated by detecting a first physical downlink control channel (PDCCH) with a downlink assignment index (DAI) value equal to 1 or a second PDCCH with a DAI value equal to 2 is received, or if a first semi-persistent scheduling (SPS) release PDCCH with a DAI value equal to 1 or a second SPS release PDCCH with a DAI value equal to 2 is received, among the four candidate resources, a first resource is determined based on a first control channel element (CCE) used in transmission of the first PDCCH or the first SPS release PDCCH, and a second resource is determined based on a first CCE used in transmission of the second PDCCH or the second SPS release PDCCH.