Fuente: Wipo "digitalization" The present invention discloses a method, an apparatus and a system for transmitting communication signals, and relates to the field of communications. The method includes that: a multifrequency receiver divides RF signals received from an antenna into the RF signals with different frequency bands, and transmits a first part of RF signals with a predetermined frequency band to an RF unit, so that the RF unit transforms the received first part of RF signals with the predetermined frequency band into first base band digital signals and transmits the first base band digital signals to a base band processing unit; the multifrequency receiver transforms a second part of RF signals with the predetermined frequency band into second base band digital signals, and transmits the second base band digital signals to the base band processing unit through a digital base band interface, or transmits the second base band digital signals to the RF unit through the digital base band interface, so that the RF unit transmits the second base band digital signals to the base band processing unit. The present invention is mainly applied to the process of multifrequency reception, and can improve the reception performance of networks.