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demonstration booth to present a part of the results of our research and development; at the 19th meeting (AWG 19) held in February in 2015, we presented a working docu-ment for the preparation of the preliminary report on the drone services and applications for public business opera-tions [8]; in addition, at the meetings of ICAO, we pre-sented the results of the measurements we conducted on the radio wave propagation characteristics in the 5 GHz band and made a proposal on the frequency sharing tech-nologies.On the other hand, under the R&D administration committee of this project, an association was established, the “Liaison Council of the Organizations involved in Utilization Technology Development of Unmanned Aircra Systems,” participated in by 16 organizations as members from universities, national institutes, corporate laboratories and drone business associations, and six ministries and agencies as observers including MIC, MLIT, and METI. (the council is chaired by Prof. Shinji Suzuki, Tokyo University). In the years from FY2014 to 2015, six meetings were held in order to activate inter-organization collabora-tions—including ministries and agencies. e council conducted surveys worldwide and domestic trends in drone-related activities, what is required to communica-tions in each drone utilization case, and what the chal-lenges are with regard to the wireless systems; and the results were fed back to the R&D of this project.While in these days drone-related associations and others frequently hold meetings or research sessions, in those days when the council was established, such an as-sociation was very rare in Japan. So, because the council represented proactive activity for the purpose of developing collaborations between ministries and agencies, it contrib-uted to the cultivation of human networks, which have been inherited by a variety of cross-ministry committees or projects to function well.In FY2016, the consortium of NICT (the representing organization), Tohoku University, Hitachi, Ltd., and NEC Corporation received from the MIC a new research con-tract, “Research and Development of Communication Network Technologies for Eective Frequency Utilization in Unmanned Aircra Systems.” We have established a 3-year plan for the improvement of frequency utilization eciency and started our research and development ac-tivities focusing mainly on the 2.4 GHz and 5.7 GHz bands (refer to the next section) used in the “Image Transmission System for Unmanned Mobile Vehicles” developed by the ministry in FY2016.4Status of CNPC link for small UAV and radio wave allocation to robotsAlmost of all the domestically used radio control op-eration terminals are generally called “Propo,” independent of whether they are hobby use or business operation use. e 2.4 GHz band (so called ISM band) is used. As is well known, the band is widely used by wireless LAN (Wi-Fi) devices. So, drone radio control devices are less expensive and no license is required to use them. is means that the band is very convenient for both vendors and users. Furthermore, for those drones, a wireless method called frequency hopping—a number of carrier frequencies are used while being switched from one to another—is used. So, the method is resistant to wave interference, allowing a number of users to operate their drones simultaneously or even in an environment where Wi-Fi devices are work-ing close to the drone-ying area. However, such drones widely used these days, while working suciently well for hobbies or some business operations where drones y within a visible range, are operated with small power, hav-ing a narrower operation range—meaning they are unsuit-able for long-range operations, having a larger risk of receiving wave interference when used in an environment like an urban area where many Wi-Fi devices are working. In addition, because the band is used not only for control-ling drones but for telemetering or image transmission, drone system internal interferences cannot be ignored.Except for the 2.4 GHz band or the 73 MHz band for industrial use drones (mainly used for crop spraying), the 920 MHz band, which is for small-power radio stations, is one of the bands requiring no license for controlling drones FiF8　Scenes of MIC Contract Research Evaluation ExperimentDate: December 20 to 27, 2015Location: Fukushima Skypark(Fukushima, Fukushima)Participants: NICT, Tohoku University, ENRI, KDDI Laboratories, NECActivities: propagation measurement, performance while frequency sharing, evaluation of delay-tolerant and store-and-forward transmission communication, evaluation of handoverLauncher takeoff of small fixed-wing UAV used in the experiment (NICT)Small fixed wing UAVMulit-rotor type UAVAir-to-air link experiment using a small fixed-wing UAV and multi-rotor type UAV in flight (Tohoku University)AeroMACSmobile station（ENRI）Visited by the special investigation team (SIT) of Fukushima Prefectural PoliceMulti-rotor type UAV used in the experiment (Tohoku University)Student collecting data(Tohoku University)Setting a fight course to UAVMounted store-and-forward communication unit in the payload space (KDDI Labs)UAV-mounted 5GHz band repeater unit developed, performing propagation measurement, network coding, and hand over632-9 Wireless Communication Technology for Small Unmanned Aircraft Systems ~Towards the deployment of IoT in the Sky~