Smart Spectrum Management for V2X

Connected and automated vehicles (CAVs) are expected to revolutionize future transportation systems, and so, active research and development are in progress. In particular, connection functions have the potential to drive automated vehicles into the new era with cooperation and networking. Flexible wireless connection with reliability in vehicle-to-everything communication (V2X) is important for supporting various future connected applications having different demands. The reliability controlled connected function opens up new possibilities of future CAV with sharing vehicle status information, sensor information, traffic signal information under various surrounding environment. In this paper, a new smart spectrum management concept of V2X is proposed for supporting future CAV applications by using hierarchical spectrum managers with spectrum databases. In this concept, dynamic spectrum allocation and reliability prediction are realized by smartly combining spectrum measurement, modeling, database, and management. By using this concept, spectrum management can be realized by considering the surrounding radio environment and predicting the communication performance. A common V2X packet exchange process is used to derive the spectrum information by collecting the measurement data from the on-board unit installed on vehicles. A radio environment map of the exact radio propagation can be created by utilizing the measurement data collected from vehicles. A field test is performed for obtaining the measurement data over vehicle-to-vehicle communication using three vehicles. It is confirmed that the radio environment map can assist in understanding the effect of the surrounding buildings and be used for predicting the performance prior to communication. Finally, we present the challenges and future direction of the spectrum management of V2X in the future CAV era.