A method of selecting suitable frequency bands for data transmission between a network node and a user equipment within a mobile communications network. A method selects suitable frequency bands for data transmission between a network node and user equipment within a mobile communications network. A scheduler on the network node side selects data transmission mode depending on the user equipment capability of receiving data from at least two frequency bands simultaneously. The scheduler preferably selects the data transmission mode in the following way: simultaneous data transmission over at least two frequency with or without splitting traffic data or data transmission over only one available frequency band. For data transmission, a radio frame structure (Big MAC element) is dynamically established in the so-called medium access control layer, shortened so-called MAC-layer, by using concurrent radio resources from other frequency bands or other radio access technologies.