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described in Subsection 3.3, a sensor terminal only trans-mits data it acquired via the sensors attached to it. A total of eight signage terminals were installed in three Seika Kururin buses (including one back-up bus) and ve facili-ties in the area, including the Seika Town Hall. e follow-ing information was collected and distributed in our experiments using Seika Kururin buses: government-relat-ed information from the Seika Town Hall, event informa-tion from the Kansai-kan of the National Diet Library and trac information from Nara Kotsu Bus Lines [14]. We noticed that there were strong public demands for the Seika Kururin Bus to provide bus location notication service due to infrequent community bus operations in the subur-ban environment of Seika Town. To put this service into practice, it was necessary to grasp the location data of all buses in operation across the Seika Kururin Bus routes in semi-real time. erefore, we installed 250 mW communi-cation devices in three Seika Kururin buses to enable transmission signals from these buses to travel farther distances.In addition, we installed three simple rooop terminals in the testbed in addition to the ve standalone rooop terminals already respectively installed on the top of the Seika Town Hall building and at the other locations (Fig. 6). is arrangement enabled these rooop terminals to receive bus location data transmitted from arbitrary locations along the bus routes. For convenience of description, we named the eight rooop terminals T1 through T8 in Fig. 6. e addition of the three simple rooop terminals (T6, T7 and T8) reinforced coverage over the Seika Kururin Bus routes as shown by dotted lines in Fig. 6. e addition also increased redundancy in the rooop terminal network. As a result, each rooop terminal established two to six links with other rooop terminals, which strengthened bus loca-tion data sharing between the terminals (Fig. 6). e range of coverage may become smaller if high-voltage public outlets become unavailable for some reason. However, the network established among the ve standalone rooop terminals (indicated by solid red lines in Fig. 6) can main-tain operation.Shin-HosonoStationShimokomaStationYamadagawaStationSeika Town HallIketaniNursery SchoolSeikadaiElementary SchoolYamadashoElementary SchoolHosonoInformation CenterVending machine No. 1MukunokiCenterVending machine No. 2KeiHanNaPlazaSignage terminalRooftop terminalSensor terminalLegend:Bus routeSimple Rooftop terminalNICTKICKKashinokienT1T2T3T4T5T6T7T8FiF6　Testbed established around the Seika Kururin Bus line4s 4s2s 2s2s2s4s 4s2s 2s2s2sT8T7T4T5T2T3T1T6S-F&SenS-F&SenS-BS-BOne frame(60s)Sync.4s 4s2s 2s2s2s4s 4s2s 2s2s2sT8T7T4T5T2T3T1T6S-F&SenS-F&SenS-BS-BS-B: a signage terminal mounted in a busS-F: a signage terminal mounted in a facilitySen: sensor terminalFiF7　Transmission time frame example492-7 Development and Field Trial of D2D Networks for Local Area Information Collection and Distribution