The described examples are usable in an authorized shared access system to provide a front end sub-band filter system and method that securely allows the selection of a front end sub-band filter for receiving signals in a shared radio frequency spectrum (SRFS). A controller manages allocation of communication channels in the SRFS using an encrypted signal. The encrypted signal is only decrypted by a filter controller of a filter selection system. Based on the decrypted signal, the filter controller instructs a filter switch which band pass filters are to be incorporated into a front end communication path. The encrypted signal prevents unauthorized users from accessing a communication channel, and the selection of a specific sub-band filter prevents transmitter interference into other communications channels in other sub-bands, and prevents the reception of signals or interference from other communications channels in other sub-bands.