Thread by @stromgade

Extremely interesting interview of academician Li Deren on the future of Chinese Earth observation: translate.google.fr/translate?sl=a…
(original: mp.weixin.qq.com/s/-x7Du8uW-KOJ…)

On the dual nature of the Gaofen satellites "a total of 14 satellites after years of research, which are what we now call high-resolution earth observation satellites, of which 1-7 are civilian satellites, and 8-14 are military satellites ...

.. These 14 satellites can be said to be a full military-civilian integration"

He confirms a resolution of 0.1m for GF-11, as expected: satelliteobservation.net/2018/08/02/gf-…

He also says the radar satellites reach 0.5m (presumably for the newest, GF-12), and that GF-13 has 15m resolution.

There is a lot of discussion on stereo mapping, and on reducing data latency. On the latter three examples are given:

1) tracking ships in the China Sea from LEO, and using a GEO relay sending it to users in less than one minute.[That makes the ocean surveillance constellation a very lethal system: satelliteobservation.net/2016/09/20/the…]

2) Detecting fires using a thermal IR payload and distributing the detections directly to firemen's phones using the Beidu SMS service

3) Adding navigation payloads to EO satellites to improve user's geolocation accuracy.

He states China is moving to an integrated PNTRC concept (Position, Navigation, TIming, Remote sensing, Communications), in three steps: first, a local coverage of the chinese coasts with 20 LEO sats and three GEO relays,to get a revisit every 15 minutes

Then, a regional coverage of China and the Belt & Road countries with 50 optical, 50 radar and 150 communication satellites.

Finally, a global coverage every 5 minutes, with 200 EO and 300 comms satellites.

This is very similar to the american approach led by the Space Development Agency: satelliteobservation.net/2020/06/06/the…

Thanks @luritie and @HenriKenhmann for pointing out the interview!