Official name TJS-4
Alternative name TJS-4
Cospar ID 2019-070A
Norad ID 44637
Launch date 2019-10-17
Launch site XSC
Launch vehicle CZ-3B/G3
Country/Organization China
Type application SIGINT ?
RCS size LARGE
Decay date ON ORBIT
Period (min) 1436.13
Inclination (deg) 0.07
Perigee (km) 35770
Apogee (km) 35805
Eccentricity 0.000488997555012225
Mean motion (revs. per day) 1.00269474211945
Semi-Major axis (km) 42165.635
Raan (deg) 76.3609
Arg of perigee (deg) 355.795
Shape Box + 2 Pan + 1 Dish
Mass (kg) 4000
Height (m) 5
Width (m) 2.5
Depth (m) 2.5
Contractors CAST
Power 2 deployable solar arrays, batteries

TJS 1 (Tongxin Jishu Shiyan) is a Chinese geostationary satellite billed as a communications technology test satellite, but which is likely a military SIGINT mission.

The satellite is repordedly mainly used to conduct a test on Ka-band in broadband communication. Also it has been reported, that it features a large unfulable dish antenna of ~32 m diameter. It has been positioned at 154.5° East.

The lack of public information has lead to the suspiction, that this satellite has a military mission. It has been speculated, that the satellite might be in fact a military Qianshao-3 SIGINT satellite.

TJS 1 was launched in September 2015 on a CZ-3B/G2 rocket.

A second sarellite of this type, TJS 4 (Tongxin Jishu Shiyan), was launched in October 2019 into a geostationary transfer orbit.

Reportedly the satellite was built by CAST and is a technological demonstration of multi-band, high speed communication techniques. The launch animation showed a satellite featuring a deployable mesh antenna and a number of smaller antennas, hinting to a SIGINT mission.

Satellite COSPAR Date LS Launch Vehicle Remarks
TJS-1 2015-046A 2015-09-12 XSC CZ-3B/G2
TJS-4 2019-070A 2019-10-17 XSC CZ-3B/G3
TJS-9 2021-135A 2021-12-29 XSC CZ-3B/G3