Super-Large-Coverage Standardized Wireless Communication System and Its Implementation in VHF Band for IoT and V2X

This article presents a comprehensive evaluation of the performance of a super-large-coverage mobile communication system for wireless regional area networks (WRANs) in the very-high-frequency (VHF) band. The system was standardized as ARIB STD-T103 and IEEE 802.16n. It can transmit data over a distance of 10 km or more at a transmission rate of several megabits per second (Mbps). It is particularly suitable for transmitting sensor and monitoring information, including moving images, over a wide area. First, we present some use cases and determine the feasibility of implementing WRANs for vehicle-to-everything (V2X) and the Internet of Things applications. Subsequently, we evaluate the transmission performance and estimate the transmission distance in the VHF-band radio propagation environment through computer simulations and experimental evaluations with our WRAN prototype. In the evaluation, we also adopt several channel estimation methods for a particular pilot pattern in the downlink. Moreover, we demonstrate the transmission distance that can be achieved with and without a multihop relay based on the evaluation results. Single-hop transmission reaches up to approximately 10 km while maintaining transmission speeds of several Mbps on the uplink, when QPSK is used. Conversely, by using multihop transmission, although the transmission speed is approximately 1/2 to 1/6, the maximum transmission distance is approximately 50 km.