Effect of non-integer delay on ranging accuracy for ultra-reliable systems

Ultra-reliable communication systems are drawing a lot of attention due to the rising demand on new wireless technologies for safety critical applications. Many of these applications require ultra-reliable distance estimation between the communicating nodes. Automatic coupling between train wagons is one of the scenarios where ultra-reliable communication and ranging at short distances is required. The main objective of this paper is to define a theoretical channel model for the aforementioned scenario, to define a proper discrete equivalence of the communication system model, and to derive Cramer Rao Lower Bounds for ranging accuracy. Ranging accuracy simulation results are provided using three systems: ITS-G5, IR- UWB, and a proposed 5G wide band system operating in the mm-Wave frequency band. We show from the results that the proposed mm-Wave system is suitable for ultra-reliable ranging at short distances.