ified without causing any of the existing users to become unqualified as a result of the extra interference. The scenario considered is the traditional "blocked calls cleared": those users that are not qualified have their RBs released and the connections marked as rejected and not considered further. (It would also be possible to set the scenario as "blocked calls queued" but for simplicity that is not considered here.) The basic steps of CAC are as follows, but the details of each step vary with the imple- mentation chosen, as explained later: Whenever a new user comes, 1. store the current RB allocation and co-channel interference map; 2. mark all existing QUs as PrUs (protected users); 3. use the game-theoretic approach to allocate resources to all the unqualified users (RB reallocation); 4. if the existing (protected) users have become unqualified, provide extra resources to those users to meet their desired SINRs (PrU compensation); 5. if one or more PrUs is still unqualified, loop back to step 3 until the result converges or the maximum number of iterations is reached, or all the users become qualified; 6. In the end, if one or more PrUs still cannot meet the desired SINR, reject the new user and roll back to position at step 1 and end; if all PrUs are qualified, the new RB allocation will be recorded and the new user is accepted. The concept of PrUs is derived from the PUs in CR networks [56] but it should be noted that all existing users are PrUs at the start of each optimization round SO the scenario generally contains many PrUs, but only one new user (equivalent to the SU in CR). As the emphasis of this example is on demonstrating the effectiveness of the CAC in providing 8 Network Slicing with Spectrum Sharing isolation, for simplicity only one type of user is considered. However, mixing users that have different characteristics (i.e. belonging to different slices) is straightforward as explained in Yang et al. [32]. This example again uses a seven-cell cluster with wrap-around for an OFDMA uplink usi