nter-slice interference, unless other actions are taken. A consideration is how to specify some limits to the sharing between slices in this case for the admission control to use. The following approaches are feasible ([18] and Section 1.2.3): A defined spectrum sharing ratio (SR): this is more usefully specified as a minimum share for each slice. Number of qualified users: sharing spectrum does not guarantee that any required number of qualified users is achieved as that depends on channel conditions and user distribu- tion. An alternative is to consider the number of qualified users per slice, or at least the ratio of qualified users between slices. To do this, the implicit spectrum sharing concept of Liu et al. [18] can organize the allocation to users to achieve the required ratio between qualified users in the slices. The steps in the algorithm are as follows: (i) Initial prioritized RB allocation: In every cell, the sectors allocate RBs to their users in the appropriate serving order [14]. As no ICI can be obtained beforehand, the num- ber of RBs required by each user is estimated by taking into account noise, channel conditions, and fading, but assuming there is no ICI. The lack of consideration of inter- ference means that many users become unqualified after the first round, but this can be mitigated by adding extra RBs as a "guard band." (ii) RB release: Releases the RBs of the users who do not reach Cmin (these are called unqualified users) and puts those released RBs back into the unallocated RB pool. (iii) RB reallocation: Reallocates the unallocated RB pool to unqualified users and keeps a record of the number of which RBs are used. As RBs are allocated to unqualified users, the interference map will change SO that some previously qualified users may become unqualified. In this case, extra RBs must be allocated to those users, or the actual RBs may be changed to those suffering a lower interference. (iv) RB release: As in step (ii) (v) Go back to RB reallocation and continue the process until the RB 