Unmanned aircraft systems have recently been considered as effective solutions to establish communication network infrastructures in isolated regions, and perform environment-related tasks such as crop monitoring and topographic surveying. In a UAV network, the data from onboard video cameras, sensors, and communication devices are retrieved by a ground station. The performance of this type of network depends on efficient resource allocation to achieve a high throughput under the usually limited frequency bands. Thus, we introduce an architecture and a resource allocation system for UAV networks. In addition, we present the results from different field experiments and discuss future research directions based on these results. We expect that this study will foster the development of UAV networks for the service of society.