Method for allocating radio resources, and radio resource allocator

A radio resource allocator device arranged for allocating radio resources in a radio access network including radio resource allocators of different hierarchical layers, the network comprising at least one first layer having at least one first resource allocator and at least one second layer having at least one second resource allocator, the first layer being a hierarchical higher layer in relation to the second layer, the radio resource allocator being a first radio resource allocator and configured to:

• decide if a second radio resource allocator of the second layer should operate in an autonomous mode or in a controlled mode for at least one portion of available radio resources;
• and
• allocate at least one portion of available radio resources to second radio resource allocator if it is decided that second radio resource allocator should operate in the autonomous mode, wherein at least one portion of available resources is further allocated by second radio resource allocator to its radio resource users or radio resource allocators of a third lower layer, and
• allocate the at least one portion of available radio resources to radio resource users of second radio resource allocator or radio resource allocators of a third lower layer if it is decided that the second radio resource allocator should operate in the controlled mode.