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to a dierent channel, the fore STA and rear AP autono-mously connect to set up an ad-hoc network for multiple channels. With the assistance of the crisis management oce, general aairs department, Hokkaido Prefecture, Hokkaido re academy, the re department headquarters of Ebetsu City, the re department headquarters of Kita-Hiroshima City, and the re department headquarters of the re department aairs association of Iwamizawa dis-trict, we installed 10 network nodes on the re vehicles and mobile vehicle earth station which can communicate through WINDS while in motion, and conducted basic empirical testing on the public roads in Ebetsu City, Hokkaido Prefecture. As the result, we could conrm that under vehicle stopping, 90 percent or more of the node pairs between vehicles had eective TCP throughput of 10 Mbps or more (Table 3). In addition, we conrmed that a high-denition image could be streamed to the internet through the network between traveling vehicles and the satellite. Figure 6 shows the mobile communication ex-periment between vehicles using the re vehicles and WINDS mobile vehicle earth station, and Fig. 7 shows the image streamed from the front vehicle to the internet through the network between vehicles and WINDS.3.3Speech quality evaluation of voice communication system using WINDSWe evaluated the sound quality for whether under-standing is possible when connecting to a telephone net-work using a WINDS line and the voice communication system.3.3.1Configuration of network for speech quality evaluationFigure 8 shows the network conguration built for the speech quality evaluation. e WINDS line is built by the 24 Mbps regenerative mode, and AP of Wi-Fi is placed on the mobile vehicle earth station. e order for the com-munication path to call a xed telephone from smartphone A is as follows: Smartphone A ⇔ Wi-Fi on the mobile vehicle earth station ⇔ WINDS ⇔ fully automatic por-table earth station ⇔ IP-PBX ⇔ optical telephone GW ⇔ xed line network ⇔ xed telephone.3.3.2Conditions for speech quality evaluatione speech quality evaluation methods include “subjec-tive sound quality evaluation methods” and “objective sound quality evaluation methods.” e subject speech quality evaluation methods allow many estimators to correctly evaluate and directly evaluate the speech quality, but require much time and costs. On the other hand, the objective speech quality evaluation methods are oen used because the entrenched objective sound quality evaluation methods which estimate the same value as the value obtained by the subjective sound quality evaluation method from physical characteristics of the sound can reduce the time and costs and have the advantage that the method always outputs the VehicleearthstationMobilevehicleearthstationVehicleno.1Vehicleno.2Vehicleno.3Vehicleno.4Vehicleno.5Vehicleno.6Vehicleno.7Vehicleno.8Vehicleno.9Vehicle earthstation22.614.752.270.171.574.645.733.892.22.88Mobilevehicle earth19.7316.2717.8414.6914.5114.1112.8310.08-Vehicle no.122.2919.1918.6118.1918.1612.6414.8812.93Vehicle no.222.2917.0115.8713.1716.2113.7111.44Vehicle no.322.1918.9119.7316.8316.0310.29Vehicle no.419.6816.8316.5314.24-Vehicle no.519.5713.639.8411.89Vehicle no.619.2515.79-Vehicle no.718.5312.48Vehicle no.813.89Vehicle no.9stationTabT3　TCP throughput of vehicle pairFiF6Appearance of mobile communication experience using fire vehicles and mobile vehicle earth station for WINDSFiF7　Screenshot of streaming data from the front vehicle913-3 Development and Demonstration Experiments on Satellite Communication Effective for Disaster Countermeasures