In connection with the appearance of ballistic missiles in the DPRK, in the mid-1990s, the Japanese government decided to begin research in the field of a national anti-missile defense system. Practical work on the creation of missile defense started in 1999, after the North Korean Tephodong-1 missile flew over Japan and fell into the Pacific Ocean.
The first step in this direction was the use of existing stationary radars for the detection of ballistic missiles, as well as the additional deployment of American-made Patriot PAC-2 air defense systems. In December 2004, a framework agreement was signed with the United States, according to which an echeloned missile defense system should be created on the territory of the Japanese archipelago.
In the 21st century, the Japanese Self-Defense Forces received modernized and new radar missile attack warning systems, Patriot PAC-3 anti-aircraft missile systems with expanded anti-missile capabilities, and in cooperation with the United States, the creation of a naval missile defense component began.
Japanese early warning missile radars
The foundation of any national anti-missile system is the means of detecting and issuing target designation: over-the-horizon and over-the-horizon land-based and sea-based radars, as well as spacecraft equipped with infrared sensors.
Currently, Japan is developing geostationary artificial earth satellites designed to fix the launches of ballistic missiles. The construction of a missile attack warning system based on a network of Japanese and American stationary and mobile radars is close to completion.
The first Japanese radar capable of detecting and steadily tracking ballistic targets was the J / FPS-3. The pilot operation of this type of head radar began in 1995. In 1999, 6 such stations were already on duty.
A three-coordinate radar of the decimeter range with an active phased antenna array rotating in azimuth is stationary on a concrete base. For protection from wind and precipitation, the antenna post is covered with a plastic radio-transparent dome.
All J / FPS-3 radars are built on higher elevations, which allows to increase the detection range. Initially, the J / FPS-3 radar was mainly designed to work on aerodynamic targets, which it can see at a distance of more than 450 km. It is reported that this station managed to fix a real ballistic target at a distance of more than 500 km. The maximum height is 150 km. When working on ballistic missiles, the sector mode of viewing the airspace is used.
The Japanese J / FPS-3 radar was developed to replace the outdated two-coordinate American AN / FPS-20 tube stations and AN / FPS-6 altimeters, and the ballistic missile detection and tracking function began to be used after commissioning. For anti-missile defense applications and improved operational characteristics, the manufacturer Mitsubishi Electric has brought all available radars to the level of J / FPS-3 Kai. The advanced modification is known as the J / FPS-3UG. The J / FPS-3ME radar is offered for export.
In 2009, after modernization, all Japanese J / FPS-3 radars were connected to the JADGE (Japan Aerospace Defense Ground Environment) automated air defense / missile defense system.
Real-time aerodynamic and ballistic target information is transmitted directly over underground fiber optic cables. Upgraded radio relay communication stations built during the Cold War are used as backups.
Taking into account that the J / FPS-3 radars are not optimal for detecting ballistic missiles and, when operating in missile defense mode, they cannot conduct a circular search for air targets, in 1999 the 2nd Department of the Institute of Technical Research and Development of the Ministry of Defense of Japan and an experimental group on the development of aviation began to create a specialized radar with an increased energy potential.
Research conducted as part of the FPS-XX R&D led to the creation of an experimental radar in 2004. Tests of the prototype from 2004 to 2007 were carried out at a test site located northeast of the city of Asahi, Chiba Prefecture.
The experimental radar was a pseudo-triangular prism, on two sides of which there were antenna sheets of different diameters. The height of the radar is 34 m, the diameter of the large track is 18 m, and the diameter of the small one is 12 m.
The large track is for missile tracking, the small track for aircraft. The base of the radar could be rotated in azimuth. Ballistic targets are detected in the frequency range of 1-1.5 GHz, aerodynamic targets - 2-3 GHz.
The radar station, put into service under the designation J / FPS-5, has a very unusual design. For the characteristic shape of the radio-transparent vertical dome in Japan, this radar received the nickname "Turtle".
In 2006, the Japanese Cabinet of Ministers approved the allocation of the equivalent of $ 800 million for the construction of four missile warning radars. The first station was commissioned in 2008 on Shimokosiki Island, Kagoshima Prefecture. Previously, the J / FPS-2 radar functioned here.
The second station was built on Sado Island (Niigata Prefecture) on the summit of Mount Mikoen at an altitude of 1040 m above sea level. Commissioning took place at the end of 2009.
In 2010, the upgraded station J / FPS-5B was launched, located at the northern tip of the island of Honshu, near the Japanese naval base Ominato.
At the end of 2011, the newest J / FPS-5C radar was put into operation. This station was built in the southern part of Okinawa Island, next to the Naha Air Base.
There are not many details about the real characteristics of the J / FPS-5 radar in open sources. Although Japanese sources say that the base of the station can be deployed, satellite images show that all the radar beds are constantly oriented in the same directions. Unlike the prototype, serial early warning missile radars have three blades: one for tracking ballistic missiles, the other two are designed to detect aircraft and cruise missiles.
It is stated that several J / FPS-5 radars can operate in parallel in bistatic mode (reception of radiation transmitted by neighboring radars), thereby improving the ability to detect air targets with low radar signature. Thanks to the modular design, multiple duplication and the use of automatic self-diagnostics, it was possible to achieve high reliability of the stations put into operation.
According to the Japanese media, the real detection of the launch from the DPRK of the Gwangmyeongseon-2 missile using the J / FPS-5 radar was first carried out on April 5, 2009. The maximum tracking range was 2,100 km. The station detected the launch in time, and based on the data received, the calculated trajectory was determined. Since the North Korean missile was supposed to fly over Japan and fall into the ocean, the anti-missile defense forces were not put on alert.It is reported that with the help of the J / FPS-5 radar, it was possible to track training launches of ballistic missiles from Russian strategic submarines in polar latitudes.
Currently, the J / FPS-5 radar is the main Japanese missile warning device. The more numerous J / FPS-3 radars, also capable of tracking ballistic missiles, are auxiliary.
Due to the high cost of the J / FPS-5 over-horizon stations and the need to replace the no longer new universal J / FPS-3s, in 2007 the Air Self-Defense Forces command announced a competition for a new radar, in which, at a relatively low price, the advantages of these two were to be combined. radars. In 2011, NEC was announced the winner of the competition. It is reported that the radar, designated J / FPS-7, has three antennas with AFAR, which work separately for aerodynamic and ballistic targets. The cost of building one stationary radar is about $ 100 million. Initially, this radar was not intended to detect ballistic missiles, but after revision it got this opportunity.
Construction of the first station began in 2012 on Mashima Island, in the northern part of Yamaguchi Prefecture. The launch of the radar took place in 2019. Information about air and ballistic targets is transmitted through large parabolic antennas of radio relay equipment J / FRQ-503. In addition to the stationary J / FPS-7 radar, the J / TPS-102 mobile radar with a cylindrical antenna operates in the area.
The second station J / FPS-7 was built in 2017 in the central part of the island of Okinawa, on the territory of the Nohara radio interception center, from which reconnaissance information is broadcast to the Naha air base. The launch of the J / FPS-7 radar in Okinawa took place at the end of 2019.
Since 2017, on the island of Okinoerabujima, in Kagoshima Prefecture, the construction of the third J / FPS-7 radar has been carried out. Its work in test mode began in the fall of 2020.
In Japan, it is planned to build two more radar radars J / FPS-7, which should replace the outdated fixed station J / FPS-2. The J / FPS-7 radars are currently in trial operation. Their entry into permanent combat duty is scheduled for 2023.
American-made missile warning radars
In June 2006, the United States and Japan reached an agreement on the deployment of the AN / TPY-2 radar on the Japanese islands. This mobile radar, created by Raytheon, operates in the frequency range of 8, 55-10 GHz. The AN / TPY-2 radar, designed to detect tactical and operational-tactical ballistic missiles, track and guide interceptor missiles at them, is part of the THAAD anti-missile system (Terminal High Altitude Area Defense - a mobile anti-missile system for high-altitude transatmospheric interception), but can be used separately if necessary.
The AN / TPY-2 radar can be transported by air and sea transport, as well as in towed form on public roads. With a detection range of 1,000 km warheads and a 10–60 ° scanning angle, this station has good resolution sufficient to distinguish a target against the background of debris of previously destroyed missiles and detached stages.
The first American AN / TPY-2 radar was deployed in a designated area near the US Army communications center in the vicinity of the village of Shariki (Aomori Prefecture) in October 2006. Two Japanese batteries of Patriot PAC-3 air defense systems are also located in this area.
A second radar was commissioned in 2014 at a newly built base near the Kyogamisaki Air Defense Forces radar post west of Kyotango in Kyoto Prefecture.
According to information published in the Japanese media, the radar at the Shariki facility is not on constant duty and is activated only upon receipt of intelligence information about the preparation of missile launches in the DPRK.
For the American AN / TPY-2 radar, deployed in Kyogamisaki, a radio-transparent dome was built to protect against adverse meteorological factors.
The radar, deployed in Shariki, serves the personnel of the 10th Anti-Ballistic Missile Battery of the US Army, the facility in Kyogamisaki is controlled by the 14th Anti-Ballistic Missile Battery. The total number of both units is a little over 100 people. The 10th and 14th batteries are part of the 38th Air Defense Brigade, which is led by the 94th Air and Missile Defense Army headquarters at Fort Shafter, Hawaii.
The AN / TPY-2 radars, under the control of the US military, deployed in Japan and the Republic of Korea, provide control of North Korean missile launches, scan part of the PRC territory and capture the southern regions of Russian Primorye.
In connection with the emergence of information about the construction in North Korea of submarines capable of carrying ballistic missiles, the Japanese leadership is considering the option of placing another AN / TPY-2 radar on the island of Okinawa.
Japan is actively pushing the United States to do this, fearing surprise nuclear missile attacks on the Kadena airbase located in Okinawa, which is a key factor in the American military presence in the region.
In 2017, information appeared about Japan's intention to build a radar station designed to track "space debris". This radar was supposed to be located on the territory of one of the facilities of the Japanese Self-Defense Forces in the western prefecture of Yamaguchi. It is stated that the main task of this radar will be to obtain operational information about the movement of debris near Japanese satellites in order to correct their orbit in the event of an immediate threat of collision. The Japanese Defense Ministry has requested the equivalent of $ 38 million for research purposes.
In 2018, it became known that Japan intends to acquire two AN / SPY-7 (V) long-range over-the-horizon radars. During development, this Lockheed Martin station was known as LRDR (Long Range Discrimination Radar). The AN / SPY-6 radar proposed by Raytheon also participated in the competition. The launch of the first Japanese radar AN / SPY-7 (V) is scheduled for 2025.
It is a modular station with gallium nitride solid-state cells, with an active electron scanning grating. The antenna consists of individual solid-state blocks that can be combined to increase the size of the radar. It is stated that AN / SPY-7 (V) operates in the frequency range 3-4 GHz and is twice as wide as the AN / SPY-1 radar.
According to a Lockheed Martin spokesman, the Japanese company Fujitsu participated in the development of the AN / SPY-7 (V) radar. The cost of deploying a similar missile defense station in Alaska exceeded $ 780 million. Due to the participation of Japanese companies in the construction of radar stations and the use of components of their own production, the command of the Air Defense Forces intends to significantly reduce the cost of the radar life cycle.
The AN / SPY-7 (V) radars are part of the Aegis Ballistic ground-based missile defense system, which, according to Japanese officials, could be deployed to defend against North Korean ballistic missiles.