Distributed Spatial Channel Emulation for Virtual Drive Testing Based on Multiple Software-Defined Radios

Following a strong trend towards cognitive connected cars, modern automobiles are equipped with a multitude of wireless communication systems. In order to ensure proper functionality, reliability, and resilience of these systems, the development of suitable test facilities and verification methods is of great interest in current research. An established testing method is the concept of channel emulation, in which temporal and spatial characteristics of mobile communications are reconstructed in a lab environment, in order to allow for reproducible and stable test conditions. Under the roof of the Thuringian Center of Innovation in Mobility in Ilmenau, Germany, the virtual road simulation and test area - VISTA was installed and laid out for virtual drive testing. This paper presents a distributed spatial channel emulator, which is based on multiple commercially available software-defined-radio modules and can be deployed in an over-the-air measurement setup. Pursuing a cluster-based measurement concept, it allows for reconstructing essential features of electromagnetic wave propagation in the wireless automotive communication channel. In this paper, the implementation of the distributed channel emulator is described and its feasibility demonstrated in principle.