Comparison of several sensor deployments in wireless sensor networks

In wireless sensor networks, the number of sensor nodes has direct relation to the cost of total wireless sensor networks, and at the same time, the problem is closely connected to wireless sensor networks´ performance, such as robust, fault-tolerance, and furthermore, it is considered at first as wireless sensor networks are designed. Therefore, the research on the number of sensor nodes has significant meanings of theory and practice to design of wireless sensor networks. By computation and analysis, the sensor deployments in the form of equilateral triangle, as a rule, are better than those in the form of square, and the efficient coverage area ratios decrease with increasing number of sensor nodes.