At present surveillance equipment on the ground of the army is distributed and located by experience element and intellience preparation of the battle field. Therefore, it is hard to utilize the optimal detection capability. This paper is forcused on improving watch ratio of the named area interested(NAI) and maximizing detection area. A linear programming model is developed and network model is established on the basis of the linear programming model. And then Out-of-Kilter algorithm is utilized for the optimal solution. Finally, one of the example is provided it shows that this model minimizes the non-detection area.