When unmanned aerial vehicles (UAVs) are used for surveillance, information must often be transmitted to a base station in real time. However, limited communication ranges and the common requirement of free line of sight may make direct transmissions from distant targets impossible. This problem can be solved using relay chains consisting of one or more intermediate relay UAVs. This leads to th...

In this paper, we consider unmanned aerial vehicle (UAV) assisted cellular communication systems where UAVs are used as amplify-and-forward relays. The effective channel with UAV-assisted communication is modeled as a Rayleigh product channel, for which we derive a tight lower-bound of the ergodic capacity in closed-form. With the obtained lower-bound, tradeoffs between the transmit power and t...

Brigham Young University recently introduced a project for undergraduates in which a miniature unmanned aerial vehicle system is constructed. The system is capable of autonomous flight, takeoff, landing, and navigation through a planned path. In addition, through the use of video and telemetry collected by the vehicle, accurate geolocation of specified targets is performed. This paper outlines ...

The availability of new information can often necessitate rerouting of a vehicle. In [1], the set of nonoverlapping useful vicinities of the reconnaissance sites, S, and the 3D space over them was represented using a discrete graph-model. Here, we consider two cases in which an unmanned reconnaissance aerial vehicle must be rerouted. The first scenario involves not visiting useful vicinities, S...

Given significant mobility advantages, UAVs have access to many locations that would be impossible for an unmanned ground vehicle to reach, but UAV research has historically focused on avoiding interactions with the environment. Recent advances in UAV size to payload and manipulator weight to payload ratios suggest the possibility of integration in the near future, opening the door to UAVs that...

This project aims at a system for an Unmanned Aerial Vehicle (UAV) following moving targets on ground. The UAV has physical constraints on airspeed and maneuverability. The target however can move freely and in any general pattern. We assume minimum knowledge about the target while navigating the aircraft. The system includes visual tracking of the target with a camera mounted on the UAV. The c...

Despite the name Unmanned Aerial Vehicle (UAV), humans are integral to UAV operations. Since the UAV’s operator interface is the primary facilitator of human-vehicle communication and coordination, an effectively designed interface is critical for successful UAV operations. To design an effective interface, it is essential to first determine the information needs for both the human and UAV comp...

The purpose of this paper is to provide a broad overview of the WITAS Unmanned Aerial Vehicle Project. The WITAS UAV project is an ambitious, long-term basic research project with the goal of developing technologies and functionalities necessary for the successful deployment of a fully autonomous UAV operating over diverse geographical terrain containing road and traffic networks. The project i...