Integrating composite urban furniture into ray-tracing simulator for 5G small cells and outdoor device-to-device communications

Small cells and device-to-device (D2D) communications will play a vital role in the realization of the next generation of wireless mobile communication systems (IMT-2020 or 5G). Both of them involve transmitters and receivers less than 10 m high inducing a more complex urban environment. This paper presents a framework of integrating composite urban furniture, e.g., traffic signs, traffic lights, etc., into ray-tracing tools. The framework starts with the theoretical modeling for radar cross section of furniture components and validation of full-wave analysis simulation in the far field. Then, in order to locally fulfill the far field condition in the small cells or D2D scenarios, the furniture is divided into small segments so that the models in the far field are still applicable. Finally, the decomposed furniture is implemented in a ray-tracing tool and validated by measurements in real scenarios. Under this framework, researchers can improve the ray-tracing tools with more essential elements of urban environment. Last but not least, this paper provides a case study to demonstrate the implementation of the framework, and the results show that the traffic signs indeed influence the vehicle-to-vehicle communications, which is one of the most frequently occurring applications of outdoor D2D systems.