The present invention relates to a wireless communication system. More particularly, the present invention relates to a method comprising: setting a first cell having a first TDD UL-DL configuration and a second cell having a second TDD UL-DL configuration; receiving a PHICH signal in a subframe #(n−L) of the first cell, or receiving a PDCCH signal in a subframe #(n−K) of the first cell; and transmitting a PUSCH signal in a subframe #n of the second cell, corresponding to the PHICH signal or the PDCCH signal, wherein the relationship between the subframes #(n−L), #(n−K), and #n is determined in consideration of a parameter value set in a specific TDD UL-DL configuration, which is the TDD UL-DL configuration having the least number of UL subframes from TDD UL-DL configuration(s), in which subframes set as UL in the first or second cell are all set as ULs.