Coverage of remote distance scene is a difficult problem in mobile network plan,the article introduces the characteristic of remote distance scene,analyses the maximum transmission distance of UMTS and transmission model over the sea,many coverage schemes for remote distance scene are also given.

In this paper,several sufficient conditions for a finite group to be supersolvable are given by means of maximal subgroups of Sylow subgroups having either semi cover-avoiding property or semi-normal property,and several known results are generalized.

The supersolvablity and nilpotency of the finite group G are characterized using the concept of cover-avoiding subgroups.