This paper presents a pulse radar system to detect drones based on a target fluctuation model, specifically the Swerling target model. Because drones are small atypical objects and are mainly composed of non‐conducting materials, their radar cross‐section value is low and fluctuating. Therefore, determining the target fluctuation model and applying a proper integration method are important. The proposed system is herein experimentally verified and the results are discussed. A prototype design of the pulse radar system is based on radar equations. It adopts three different pulse modes and a coherent pulse integration to ensure a high signal‐to‐noise ratio. Outdoor measurements are performed with a prototype radar system to detect Doppler frequencies from both the drone frame and blades. The results indicate that the drone frame and blades are detected within an instrumental maximum range. Additionally, the results show that the drone's frame and blades are close to the Swerling 3 and 4 target models, respectively. By the analysis of the Swerling target models, proper integration methods for detecting drones are verified and can thus contribute to increasing in detectability.

This paper addresses a simple democratic progress model represented by a discrete-event system (DES) and the influence of information accessibility on the progressiveness of the model. Each agent makes a decision according to its selfish criterion, and the final decision for the progress or regression of the system is done by the majority rule based on individual decisions of agents. We first present the conditions for the closed-loop system to be progressive or regressive under full observation where every agent can observe all the states. Then we focus on the masked observation problem, namely, whether the progressiveness of the closed-loop behavior can be changed by restricting the information accessibility of agents that are characterized by their masks. Especially, we show that due to the elite class, the regressive closed-loop system can never be transformed into progressive regardless of mask design, which conforms to the feature of modern democracy.