1. A method for Relay-Physical Downlink Control Channel (R-PDCCH) transmission in a carrier aggregation scenario, the method comprising:receiving, at a relay node, multiple aggregated component carriers sent by a donor base station, one or more of the component carriers carrying R-PDCCH, R-PDCCH corresponding to each of the component carriers being separately coded;

carrying out blind decoding, by said relay node, on the component carriers carrying R-PDCCH, so as to acquire R-PDCCH which is used to schedule each of the component carriers; and

acquiring physical resources, by said relay node, on the corresponding component carriers according to said R-PDCCH, and carrying out information transmission with said base station through said physical resources, wherein the method further comprises:

for the one or more component carriers carrying the R-PDCCH, and the R-PDCCH corresponding to each component carrier being separately coded, said relay node receiving multi-aggregated component carriers corresponding to the R-PDCCH sent from the donor base station, and the R-PDCCH being carried by each component carrier to independently schedule the resources on each component carrier, or said relay node receiving multi-aggregated component carriers sent from the donor base station, one component carrier carries R-PDCCH corresponding to itself and R-PDCCH corresponding to other component carriers, and said R-PDCCH schedules the resources on the component carriers in a cross-carrier way, and

if the transmission mode of the R-PDCCH refers to an interleave mode, determining, by the relay node, a starting position of search spaces in each timeslot included in each subframe on the component carriers according to the transmission mode and aggregation level of the R-PDCCH, by:

said relay node determining the starting position of the search spaces via the formula below:

L·{(Yk+m?)mod ?NCCE,jR-PDCCH/L?}+i,i=0,1, . . . ,L?1,where, L is the aggregation level of R-PDCCH;NCCE,jR-PDCCH is the number of logical CCEs (Control Channel Element) included in the pre-configured possible transmission resource set of R-PDCCH, k is the number of a current subframe, and j is the number of a current timeslot in the subframe, j?{0,1};

when the R-PDCCH carried by each of the component carriers is used to schedule the resources on each of the component carriers independently, m?=m, when R-PDCCH is used to schedule the resources on the one of the component carriers and the other ones of the component carriers in the cross-carrier way, m?=m+M (L)·nCI, m is the number of blind decodings, and nCI is the identity information of the respective component carrier where the resources scheduled by R-PDCCH exist;

Yk=(A·Yk-1) mod D, Y?1=nRNTI?0, nRNTI is RNTI of relay node, A=39827, D=65537, k=?ns/2?, ns is the timeslot number in a current radio frame;

if the transmission mode of said R-PDCCH refers to a non-interleave mode, said relay node determining the starting position of the search spaces in each timeslot included in each subframe on the component carriers according to the transmission mode and aggregation level of R-PDCCH, by:

said relay node determining the starting position of the search spaces via the formula below:

(L·m?+i)mod NVRBR-PDCCH,i=0,1, . . . ,L?1,where, L is the aggregation level of R-PDCCH;NVRBR-PDCCH is the number of VRBs included in possible transmission resources set of R-PDCCH; and

when the R-PDCCH carried by each of the component carriers is used to schedule the resources on each of the component carriers independently, m?=m, when R-PDCCH schedules the resources on the one of the component carriers and the other ones of the component carriers in the cross-carrier way, m?=m+M(L)·nCI, m is the number of blind decodings, and nCI is the identity information of the respective component carrier where the resources scheduled by R-PDCCH exist.