On November 29, a H-IIA rocket launched from the Japanese Tanegashima spaceport. The main payload was the JDRS-1 (Japanese Data Relay Satellite-1). The new Japanese data relay satellite will be used for both intelligence and civilian purposes.

Six months after the launching the Al-Amal (Hope) Mars mission for the United Arab Emirates, the Japanese again used the H-IIA rocket. It is a 53-meter high two-stage launcher fueled by liquid propellant. Its 43rd flight began on November 29 at 8:25 CET. The design from Mitsubishi Heavy Industries is very reliable as within the 43 flight history the rocket failed only once. This time it was also successful and the JDRS-1 satellite was placed in the so-called geostationary transfer orbit (GTO). Later, on its own, it will reach the target geostationary orbit (GEO).

Launch of the H-IIA rocket with the JDRS-1 satellite / SciNews

JDRS-1 intelligence uses

The Japanese government ordered the JDRS-1 satellite from Mitsubishi Electric. Due to the secret nature of the mission, many technical details were not disclosed, even such ones as mass or the target location in geostationary orbit. However, it can be assumed that the mass of the satellite is between 4.1 and 6 tons, because this is how much a H-IIA rocket can lift into GTO orbits.

JDRS-1 is to communicate directly with several intelligence satellites from the IGS-Optical and IGS-Radar series. They are primarily used to observe activities conducted in North Korea and other strategic regions for Japan.

Wizualizacja satelity JDRS-1 / JAXA
JDRS-1 satellite render / JAXA

Stosując satelitę JDRS-1 Japonia będzie mogła znacznie szybciej pozyskać z nich dane, ponieważ nie trzeba będzie czekać aż satelita znajdzie się nad wybraną stacją naziemną. Dlatego nowy japoński satelita przekazu danych na orbicie GEO pozwoli na utrzymanie łączności nawet na 40 minut z innymi satelitami krążącymi po niskich orbitach okołoziemskich. Tym samym znacznie skróci się czas reakcji japońskich służb, zarówno tych wojskowych, jak i cywilnych.

Using the JDRS-1 satellite, Japan will be able to obtain data from other intelligence satellites much faster, because there will be no need to wait for such satellite to fly over a selected ground station. At the same time, JDRS-1 location in GEO orbit will allow to maintain communication for up to 40 minutes with other satellites in Low Earth Orbits. As a result, the reaction time for Japanese services, both military and civilian, will be significantly shortened.

Civilian laser communication system

The Japanese Data Relay Satellite is also equipped with the LUCAS (Laser Utilising Communication System) instrument, commissioned by the Japanese space agency JAXA. It enables very fast data transfer using two infrared beams.

The LUCAS instrument will restore the ability to acquire satellite data quickly. Previously, the Data Relay Test Satellite (DRTS), also known as Kodama, was used for this task. However JAXA retired it in 2017 after fifteen years of use.

There is clear technical progress visible with LUCAS. The previous Kodama satellite transmitted data at a speed of 240 megabits per second. For comparison, LUCAS allows for transmissions of 1.8 gigabytes per second, which means that it will transmit seven times more data.

The JDRS-1 satellite was designed for ten years of operations. It will be jointly supervised by JAXA and the Cabinet Satellite Intelligence Center, which is part of the Japanese intelligence agency.


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