步骤1：搜索全网同BB的小区，两两计算实际距离与安全距离，当实际距离<安全距离的，生成更换BSIC清单。（注；全网指本地网与邻界小区）

步骤2：同时查找上面同BB的小区是否为邻区关系或同属某一个小区的两邻区。若是，生成更换BSIC清单。

步骤3：操作者在更换BSIC清单中选择更换BSIC的小区（两个中选择一个，一般以右列为修改对象）。具体要更换的小区以此为准。

步骤4：一个个进行修改并更新CDD

修改原则：首选网络中没有使用过的BB组合。次选距离最大化的组合。

如A、B两小区的BCCH/BSIC=50/63，现在要更换B小区的BSIC，首先搜索50号频率与64种BSIC的组合是否有未使用过的，有则用。若没有，则逐个计算各种BSIC对应小区与A的距离，最后取最大距离的小区对应的BSIC，作为B小区的BSIC。

-Step 1: searching the network with BB, to calculate the actual distance and the safe distance of two two, when the actual distance <　safety distance, generating BSIC replacement list. (note　the whole network refers to the network and the adjacent area)

Step 2: at the same time to find the above with BB area is adjacent regions or belong to a small two adjacent areas. If the replacement, generate BSIC list.

Step 3: the operator to select the replacement of BSIC cell in the replacement of the BSIC list (two choose a, generally by the right column to modify the object). Specific to the replacement of the plot to prevail.

Step 4: a revised and updated CDD

Modify the principle: preferred networks were not used in BB. Combination of time distance maximization.

Such as A, B two cell BCCH/BSIC=50/63, now to replace the B District of BSIC, combined search first 50 frequency and 64 BSIC if there are unused, is used. If not, then by calculating BSIC corresponding area and distance of A,