The first "helicopter base station" in Japan fires radio waves!Identify the location of the victims from the sky | Time & Space by KDDI

This is a Ginzanhei, Uonuma City, Niigata Prefecture, which is surrounded by 2,000m -class mountains and is buried in 5 and 6m snow in winter.

At this location, KDDI, KDDI Research Institute, Uonuma City, Niigata Prefecture, and Fujitsu have conducted a demonstration experiment on the first helicopter base station in Japan.The helicopter is equipped with a base station facilities and emits radio waves from the sky.

There is a provision for the protection of natural environments by the country around Ginzan Hei, and it is not easy to open a mobile phone base station.For this reason, there are many places where a mobile phone is not connected once you enter the mountains, and even if the victim has a mobile phone, there are cases where you cannot contact your family or fire department directly.

The purpose of this demonstration experiment is to approach the sky with a helicopter equipped with base stations facilities in areas where mobile phones are not connected, so that you can use your mobile phone.

The equipment at the base station mounted on the helicopter is compact.

The bag contains radio, battery and PC.On the right side is a latitude longitude information and an acceleration sensor on a mobile phone for identifying the current location and helicopter, and a white box is an antenna.With the "gimbal" that connects the bag and these, the helicopter aircraft keeps any posture in the sky, keeping the antenna on the ground constant.The total weight is only 7kg.This kind of size when people have.

By the time we started considering this system, the server installed in data centers and the like was very large.However, in just a few years, he was able to carry it alone and reduce the size of the helicopter.

When actually transmitting radio waves as a base station, it is used in conjunction with tablets and PCs.

The image below is visualized from the helicopter base station that transmitting radio waves to the ground.The range where the radio waves from the gray ellipse from the helicopter base station reach.Within this range, you can communicate by mobile phone.

The red dot represents the position of the captured mobile phone.In addition to sending radio waves from the sky so that mobile phones are connected, you can identify the number and position if there is a mobile phone with a powered power in the range of radio waves.You can also send SMS directly to the mobile phone you are searching for, or talk between mobile phones.

As an initiative in the "Sky Base Bureau", from 2015 to FY2017, we have been conducting demonstration experiments using drones on the theme of "to secure isolated villages in the mountains and secure communication means."。Here are the drones and communication systems used for experiments.

There are various restrictions to launch radio waves from the sky.First, do not affect existing wireless systems on land.And when using a radio that is not originally installed in the aircraft, it does not interfere with the operation of the aircraft.The former was in the jurisdiction of the Ministry of Internal Affairs and Communications, and the latter was under the jurisdiction of the Ministry of Land, Infrastructure, Transport and Tourism Air Bureau, and it was necessary to confirm that there was no problem.

In March 2018, KDDI was verified with a base station facilities in the helicopter.It was confirmed that the operating helicopter was parked, but it did not affect the instrument.And this time, I made a helicopter for the first time and conducted a demonstration experiment using the actual mountain trail.

In this demonstration experiment, the victim rescue joint training in cooperation with the local Uonuma Fire Department was also conducted.

The assumption of the joint training was to report on the fire department that "the family who went to Mt.I know the mobile phone number of the victims, but it is not possible to talk directly because the radio waves are not connected in Mt. Arasawa.Under the circumstances, the next day, the fire department set up a command station at the local Ginzanpei campsite.

All contacts are passed through this command, and search orders are issued here.Then, the helicopter base station is dispatched in parallel.

In addition, seven mountain rescue squads enter the mountains to search.

Prior to the training, we confirmed that the communication of the base station and the mobile phone did not interfere with the aeronautical radio, and then verified how much of the radio waves arrived when flying over Mt. Arasawa.

Radio waves from the helicopter toward the ground will reach a narrow range if the altitude is low.If you increase the altitude, the range will be expanded, but it will be weak.As a result of verification while changing the altitude, it was found that the best altitude in this situation was 300m.At that time, the call is about 1 up to the horizontal direction from directly below the helicopter..It was possible even if I was 6 km away.To get GPS information on SMS and ground mobile phones, it was also possible to do a maximum of 2 km from just below the helicopter.

Regarding searching for mobile phones on the ground, repeating the turn is narrowed down to some extent.

In the figure above, the orange range is a place where the location of the mobile phone is high.If you repeat the turning around these areas, you can see the location of the mobile phone with an error of about 100m.

In this joint training, he also obtained the GPS information of the victim's mobile phone, and informed the location of the victims in the flow of helicopter base station → command station → mountain rescue squad.You can also send a message directly to the victims from the helicopter base station to the suffering.

This is a message from the helicopter base station to the victims.It is very encouraging for the victim to recognize that someone is looking for himself.

When a mountain rescue squad who is searching on the ground arrives within the radio waves fired from a helicopter base station, the helicopter contacts the Mountain Relief Corps from the Helicopter that it has entered a mobile phone.Since then, the mountain rescue squad has been able to interact directly with the victims on a mobile phone.

By being able to speak directly by the victims, the mountain rescue squad can directly hear the injuries and surrounding conditions from the victims, and make appropriate rescue.A series of actions from search to rescue will be promptly deployed by collaboration between the sky and the ground.

What are the challenges of the current mountain rescue, and how can the helicopter base station this time can contribute?We asked Uonuma City Fire Department Makoto Makoto Outside.

"In Uonuma City, there are about 20 accidents in the mountains every year. Especially in the forest area of Uonuma, there are many places that are not connected because there is no mobile phone base station designated in national parks and national parks.In the case of distress proposals, the most important point is that the location information of the rescuer (victims) is the biggest point, but there are many cases where it is not possible to contact the person directly, so the range of action of the mountain rescue squad inevitably expands.That takes time to rescue. The more time it takes, the more the rescuers, the more rescuers, but also the rescue squad increases. This is a very realistic issue.

Therefore, as in this demonstration experiment, it is very effective to be able to identify the location of the rescuer by flying the radio wave of the mobile phone from the sky with a helicopter.I think that the information of rescuers is transmitted to the command headquarters, so we can narrow down the search range and reduce the search time significantly. "

As in this case, the attempt to send radio waves from the sky has been considered in the 2011 Great East Japan Earthquake.

Mobile phones are first connected to the nearest base station out of thousands of base stations nationwide, connecting to the calling partner and the Internet.For some reason, if the base station loses its functions and cannot communicate, the telecommunications company will be promptly restored.Until the work is completed, the facilities of the base station may be temporarily installed locally so that mobile phones can be used.

Depending on the size of the disaster and the damage situation, if the base station equipment can be carried to the site and installed, the "in -vehicle -type base station" or "portable base station" will be used.

The former is a vehicle equipped with a set of equipment at the base station in advance.The latter is literally "a base station that can be carried."The antenna and radio are mainly transported by vehicles and set up locally.

There is also a sea base station called the "ship -type base station".

If the roads in the affected areas have been divided, the ship is equipped with base station facilities on the ship and reach the site.During the 2018 Hokkaido Iburi East Earthquake and Typhoon No. 15 in 2019, this "KDDI Ocean Link" was anchored on the coast of the disaster area and sent radio waves.

If you cannot approach the site from the land or the sea, for example, if an accident occurs in "Yamanaka" as in this demonstration experiment, you will send radio waves from the "sky".

This time, it was specialized in mountain rescue and verified on the actual climbing route, but it is thought that it will continue to solve various issues in the future.

A helicopter that allows you to overlook the wide area in a short time. If you use the function to estimate the number and position of mobile phones, you can use the information to the government and local governments to block and block information, etc., and estimate the isolation area.It will also be effective in searching for serious people immediately after occurring.

Although searching for victims in the case of landslides or avalanches, it is necessary to continue to prove in the future, such as how much the target mobile phone is buried in soil or snow, and how much radio waves arrive.There is.

Drone base stations can also be used for volcanoes that generate toxic gas or when searching from low altitudes that can not fall off.It is also conceivable to collaborate with a smart drone autonomous operation system where research is underway.

It is now commonplace that radio waves are connected.KDDI will contribute to various issues in society by communication, assuming that if you can no longer connect.