Semi-Narrow Band Ad-Hoc Wireless Communication System (SNB-AWCS) using VHF for Disaster Response

In the domain of natural disaster management, local governments and public agencies rely on mobile devices, multi-channel access (MCA), and wireless communication methods such as administrative radio transmission and digital convenience radio to facilitate inter-organizational communication during natural disasters. However, these radio infrastructures, designed primarily for voice communication, prove inadequate for transmitting data over long distances, especially in regions prone to recurring natural disasters. This paper introduces an innovative solution called the Semi-Narrow Band Ad-Hoc Wireless Communication System (SNBAWCS), tailored to address the challenges prevalent in the northern region of Japan, where the likelihood of disasters is heightened. This solution offers the capability of independent multipoint wireless data communication, enabling effective coordination among various entities specializing in disaster management such as fire brigades and police. To substantiate our proposal, we present experimental findings from a real-world environment employing 2-Frequency Shift Keying (2-FSK) within the 220MHz band, integrated into the SNB-AWCS wireless communication system. Based on data gathered in actual conditions, our system demonstrates the capacity to sustain communication at distances of up to 20 km using omnidirectional antennas and up to 80 km with directional antennas.