Described herein are aspects related to assigning primary channels in wireless communications. An amount of available bandwidth within a radio frequency band can be determined for shared access by a plurality of operators, where each operator operates a radio access network having one of a plurality of radio communication compatibility types, and where each radio communication compatibility type defines a set of one or more compatible radio access technologies. The amount of available bandwidth can be allocated into radio compatibility type-specific bandwidth partitions for each radio communication compatibility type based on a number of the plurality of radio communication compatibility types and a number of the plurality of operators corresponding to each radio communication compatibility type. A primary channel can be assigned within at least one of the radio compatibility type-specific bandwidth partitions to at least one operator of the number of the plurality of operators.