Japan's first close coverage of the opening test of a shipboard mobile phone base station made by KDDI and the Japan Coast Guard collaborated

KDDI conducted an experiment in Kure City, Hiroshima Prefecture, in which a small base station of a mobile phone was set up on board and used as a backup when a land base station broke due to a disaster. This time, the patrol boat where the base stations are installed accompanying the experimentKurozeI was able to take a picture of taking a test to receive the radio waves from the ship that is anchored inside the ocean and on the ocean, so I will report the whole story.

The first interview site is the port of Kure City, Hiroshima Prefecture.

View Larger Map

Arrived at the Kure Port Complex, which has a mother port of the Japan Coast Guard patrol ship Kuroses with a small base station.


In addition to Japan Coast Guard, Kure's customs office and other offices are in the same building.


"I will not forgive you for white powder, do not pass through black weapons" The banner curtain was written with criminal charges such as drugs and firearms and phone number "Smuggling dial0120-461-961 ".


The port in front of the Kure Port Complex is like this.


◆Ship patrol ship

Kuroze while it is at a berth (photo left side). The purpose of this experiment is to receive radio waves from a mobile phone at a base station on board and connect it to a mobile network via a satellite line.


Experimental equipment is attached to three parts of the hull, the left is the mobile phone antenna and the base station equipment, the shadow of the hull in the central red frame is the satellite router, the right is the satellite communication antenna It is.


The diagrams of the equipment used are as follows. In the illustration inside the slide, the positions of the portable antenna and the satellite antenna are opposite to the actual ones.


Pier headed for Kuroze.


A hull of 56 m in total length and 8.5 m in full width is quite impressive when looking at close.


Characters of "Kurosame PM 35". By the way, the official name of the ship is "PM - 35 type patrol ship Kuroze".


It is written as "JAPAN COAST GUARD" on the hull.


"Coast Guard".


The height of the mobile phone antenna seen from behind the ship from the sea level is about 15 m.



The radio wave of the 800 MHz band is used for this test.


Go through the deck and under the antenna for mobile phone.


Mobile phone base station connected with antenna is like this.


Furthermore, although a router is placed ahead, it is impossible to shoot this time.


Behind the router is equipment for communicating with artificial satellites.


A parabolic antenna is stored in the radome (the cover of the hemisphere).


Looking inside it is like this.


By the way, although it has nothing to do with the experiment of this day, Kurososhi is equipped with 20 millimeter cannon.


As a mobile phone base station, perhaps the strongest armed in the country.


Next, I will head to Kurehashi-cho Osu-ku, which goes to the actual sea and conducts experiments.

View Larger Map

Coast of Omori who was surrounded by mountains and the sea and was chosen as the experiment site for this place because it is difficult for usual mobile radio waves to reach.


The surrounding town is like this.


When I asked the person who was walking about my dog, I heard that the acquaintance was told that "The phone can not connect unless it goes to a high place like the top of the levee."


◆In-vehicle mobile base station

The shipboard base station is intended to place a temporary base station in a place difficult to enter from the land, but it is possible to install the following in-vehicle mobile base station in a place where it can go by car.


An antenna is growing from the ceiling.


The tip is like this.


When you open the door behind you have a generator inside.


Inside the car.


Lots of cables.


Switchboard


◆Test of shipboard base station

Reporters and reporters gathered at the coast.


Kuroze is anchored at a location about 1 km offshore.


Dedicated device for analyzing radio waves from base stations.


The antenna looks like this.


Measuring instrument.


The waveforms when the radio waves are not output from the ship are as follows. Somewhat jaggy is due to the influence of noise.


When the base station on board blows radio waves, the waveform will change as follows.


Terminal for voice call test which is set to receive only radio waves from a base station onboard without receiving radio waves for general mobile phone.


Calling mobile phone used by people in KDDI.


The movie that shoots the state of the call in the speakerphone mode is as follows. Because it is via the artificial satellite which is over about 36,000 kilometers, a delay of about 0.5 seconds has occurred, but there is no problem in communication. The one that is reflected in the foreground is the dedicated terminal connected to the base station on the ship, and the person in the back is the mobile phone connected to the general network.

I tried talking on the radio from the ship's base station via the population satellite - YouTube


Therefore, if the base station can be set up onboard based on the results of this experiment, communication facilities will be broken due to disasters, and even if it can not be repaired quickly in the land, it will be possible to quickly make phone calls and communications You can restore it. Furthermore, it is possible to make it possible for a crew member of a large-sized ship of a size that can not distribute a satellite phone to passengers to passengers in the future to use his cell phone from the sea is.