Optimal distribution density for the fusion detection system of passive sensors

A large amount of passive sensors are deployed in the battlefield for target detecting, As they adopt passive detection, and with low cost and small volume. However, no matter active and passive sensors, the resource deployment optimization problem is quite common in practice. For the specific application of passive sensors, several reasonable approximating methods are taken to derive the optimal deployment density of passive sensors, under the "OR" fusion law of detection for the best detection probability.