| CPC H04L 5/0023 (2013.01) [H04L 5/0073 (2013.01)] | 17 Claims | 

| 
               1. An operation method of a first device, comprising: 
            identifying a first mobile terminal (MT) component carrier (CC) operating in a multiplexing mode among one or more MT CCs formed by an integrated access and backhaul (IAB)-MT constituting the first device; 
                determining first beam preference information for the first MT CC; 
                transmitting, to a second device which is an upper node of the first device, the first beam preference information; and 
                performing beam-based communications with the second device based on the first beam preference information, 
                wherein the first beam preference information includes information on one or more beams suitable for the first MT CC to use in the multiplexing mode among beams of the first MT CC and/or information on one or more beams not suitable for the first MT CC to use in the multiplexing mode among the beams of the first MT CC. 
               |