China's Space Program, News & Views

Originally Posted by NikeX

Still not clear how Chinese ocean surveillance satellites plan on distinguishing between a carrier and a similar sized super tanker with a large flat deck

It is combination of SAR,AIS,Maritime surveillance aircraft, OVH radar,Infra red imaging satellite, Optoelectronic satellite

Mpleio just posted Chinese AIS that will locate any civilian or military warship Off course US Navy can always disguise any civilian ship as warship using bogus transponder. But still they have civilian ship database to work with and using it as cross reference for suspicious warship or Aircraft Carrier. that way they can narrow down the search. Xinhui has a blog about it a year or so ago. Interesting
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This satellite image is from civilian satellite with 2m resolution .imagine what would a .5 m resolution would revealed


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Mpleio just posted Chinese AIS that will locate any civilian or military warship Off course US Navy can always disguise any civilian ship as warship using bogus transponder. But still they have civilian ship database to work with and using it as cross reference for suspicious warship or Aircraft Carrier. that way they can narrow down the search. Xinhui has a blog about it a year or so ago. Interesting

If AIS is one of the methods to be used then it is easy for the carrier or some ship in the formation to broadcast a spurious AIS signal to spoof the ocean surveillance satellite. It was done before when the IKE eluded the efforts of the Russians to pin her down in the Barent Sea.

"...In fact, in the August-September 1981 exercise, an armada of 83 US, British, Canadian, and Norwegian ships led by the carrier CVN Eisenhower managed to sail the Greenland-Iceland-United Kingdom (GIUK) Gap undetected, using carefully planned and rehearsed tactics.

Concealment and Deception
A combination of obvious if inconvenient passive measures like operating under electronic emissions control conditions and active measures like radar-jamming and transmission of false radar signals was used to hide the allied fleet. They even eluded a Soviet active-radar satellite launched into a low to search for it...."

Mpleio just posted Chinese AIS that will locate any civilian or military warship Off course US Navy can always disguise any civilian ship as warship using bogus transponder. But still they have civilian ship database to work with and using it as cross reference for suspicious warship or Aircraft Carrier. that way they can narrow down the search. Xinhui has a blog about it a year or so ago. Interesting

If AIS is one of the methods to be used then it is easy for the carrier or some ship in the formation to broadcast a spurious AIS signal to spoof the ocean surveillance satellite. It was done before when the IKE eluded the efforts of the Russians to pin her down in the Barent Sea.

"...In fact, in the August-September 1981 exercise, an armada of 83 US, British, Canadian, and Norwegian ships led by the carrier CVN Eisenhower managed to sail the Greenland-Iceland-United Kingdom (GIUK) Gap undetected, using carefully planned and rehearsed tactics.

Concealment and Deception
A combination of obvious if inconvenient passive measures like operating under electronic emissions control conditions and active measures like radar-jamming and transmission of false radar signals was used to hide the allied fleet. They even eluded a Soviet active-radar satellite launched into a low to search for it...."

Notice how dense these shipping lanes are in the Pacific. Any ship, even one the size of a carrier can easily hide among normal shipping traffic

And then there is this observation. I think this is from "Using the land to control the Sea"

".....First off, there is no guarantee that all the space based sensors in the world will necessarily reveal the locations of US naval forces. I always groan when I read such things. The Soviets had far more space based sensors than any other nation in history except the US and still could not reliably find US naval forces. All such sensors have limits penetrating weather, and can be spoofed by ECM. Naval forces can go EMCON, hide under a weather system and disappear. This was done fairly routinely against Soviet surveillance. Naval units can transmit a commercial surface search radar and appear to be a big container ship to direction finding and ELINT equipment, and can be invisible under typical north Pacific of north Atlantic overcast. ECM can be effective enough to force an opponent to fly out and physically look for naval forces their satellites and ELINT cannot find. When a carrier goes EMCON, finding it almost reverts back to WWII era tactics of patrolling with airplanes and good eyeballs. The typical weather in the northern latitudes of the Pacific and Atlantic is overcast and stormy, perfect weather for hiding from satellites. ...."

Anytime remote sensors are used as part of a surveillance system, those remote sensors can be fooled and rendered unreliable.

As I say before it doesn't just depend on 1 sensor but multiple sensors that will be fused into data collection system into database system. Then you have algorithm software to automatically detect the most probable location and eliminate the false alarm.

Then somewhere along the line you have human to verify the finding with electro optical or infra red imaging or even SAR image

As I say before it doesn't just depend on 1 sensor but multiple sensors that will be fused into data collection system into database system. Then you have algorithm software to automatically detect the most probable location and eliminate the false alarm.

Then somewhere along the line you have human to verify the finding with electro optical or infra red imaging or even SAR image

And then there is this observation. I think this is from "Using the land to control the Sea"

".....First off, there is no guarantee that all the space based sensors in the world will necessarily reveal the locations of US naval forces. I always groan when I read such things. The Soviets had far more space based sensors than any other nation in history except the US and still could not reliably find US naval forces. All such sensors have limits penetrating weather, and can be spoofed by ECM. Naval forces can go EMCON, hide under a weather system and disappear. This was done fairly routinely against Soviet surveillance. Naval units can transmit a commercial surface search radar and appear to be a big container ship to direction finding and ELINT equipment, and can be invisible under typical north Pacific of north Atlantic overcast. ECM can be effective enough to force an opponent to fly out and physically look for naval forces their satellites and ELINT cannot find. When a carrier goes EMCON, finding it almost reverts back to WWII era tactics of patrolling with airplanes and good eyeballs. The typical weather in the northern latitudes of the Pacific and Atlantic is overcast and stormy, perfect weather for hiding from satellites. ...."

Anytime remote sensors are used as part of a surveillance system, those remote sensors can be fooled and rendered unreliable.

Originally Posted by Hendrik_2000

Then somewhere along the line you have human to verify the finding with electro optical or infra red imaging or even SAR image

So you are making the case for long range ocean surveillance aircraft like the Russian TU-95 Bear and the newer American navy P-8 Poseidon?

Originally Posted by NikeX

So you are making the case for long range ocean surveillance aircraft like the Russian TU-95 Bear and the newer American navy P-8 Poseidon?

Nope Nowadays satellite has much better resolution then Surveillance aircraft Again Nike Please don't compare Soviet Satellite 30 years ago with state of the art Satellite . The SAR satellite doesn't exist back then So do IIR satellite. No automatic detection. The soviet maritime surveillance system consist of 2 or 3 satellites.No data relay,No advanced communication system. No SAR

It is because the Surveillance system is so unreliable that they need telltale in form of Bomber or ships Nothing to compare

Concealing yourself in heavy traffic could go both ways. Amongst those tankers there would always be some Chinese. These captains could radio in if there was a supercarrier on the horizon. I don't think jamming the area would be a viable option at all. It would be a disaster for a trafficked artery if there was no communication. And as Hendrik points out, the most important intelligence ability is to gather information from a range of different sources and put it together.

And yes, comparing satellite systems of the 80s to today is not without problems. It's like saying we couldn't calculate this and that because someone built a computer in the 80s that couldn't. Processing power and accuracy of satellite systems have increasied exponentially, along with the number of satellites available. Just look at how google earth has changed the ballgame for us watchers only the last few years.

Nope Nowadays satellite has much better resolution then Surveillance aircraft Again Nike Please don't compare Soviet Satellite 30 years ago with state of the art Satellite

How can you not? Ocean surveillance satellites must be in LEO (Low Earth Orbit) to achieve the resolution needed to detect ships. In the case of the Chinese satellites their use of solar power arrays puts them at a disadvantage because of the drag imposed on those arrays by the atmosphere at those low orbits. Plus for a portion of the time any solar powered satellite will be shielded from sunlight by its orbit. Hence the need for more satellites in orbit to maintain coverage. The Russians went with nuclear powered satellites because of this fact.

Orbital decay - Wikipedia, the free encyclopedia

RORSAT - Wikipedia, the free encyclopedia

"....Because a return signal from a target illuminated by a radar transmitter diminishes as the inverse of the fourth power of the distance, for the surveillance radar to work effectively, RORSATs had to be placed in low earth orbit. Had they used large solar panels for power, the orbit would have rapidly decayed due to drag through the upper atmosphere. Further, the satellite would have been useless in the shadow of earth. Hence the majority of RORSATs carried type BES-5 nuclear reactors fuelled by uranium-235. Normally the nuclear reactor cores were ejected into high orbit (a so-called "disposal orbit") at the end of the mission, but there were several failure incidents, some of which resulted in radioactive material re-entering the Earth's atmosphere...."

---------- Post added at 12:46 PM ---------- Previous post was at 12:07 PM ----------

Nope Nowadays satellite has much better resolution then Surveillance aircraft Again Nike Please don't compare Soviet Satellite 30 years ago with state of the art Satellite .

I am afraid you are wrong on that point if you are claiming the pictures transmitted by a SAR satellite are better than the eyeballs of a human observer in a P-8, P-3, and Tu-95 maritime patrol aircraft. These aircraft have advantages that satellites just do not possess. An aircraft can shadow a ship while a satellite cannot not. The key is that all nations have used patrol aircraft since aircraft first took to the sky. The method of aircraft patrolling the sea lanes is proven.

The SAR satellite doesn't exist back then So do IIR satellite. No automatic detection. The soviet maritime surveillance system consist of 2 or 3 satellites.No data relay,No advanced communication system. No SAR

Again you seem to underestimate the complexity of the Russian Ocean surveillance network. Here is the description of the Russian system.

"..... Russian military naval surveillance radar satellite. 38 launches, 1965.12.28 (Cosmos 102) to 1988.03.14 (Cosmos 1932). The US-A (later known as RLS) was a nuclear powered RORSAT (Radar Ocean Reconnaissance Satellite).
It used an active radar to track naval vessels from space in darkness and all weather.

The RLS was an element in the integrated Soviet weapons system devoted to destruction of the US Navy's surface and submarine forces. The system used space-based platforms to obtain the location of enemy forces at sea. This targeting information was provided to aircraft, surface vessels, and submarines and fed into anti-ship missiles that would attack the US forces from over the horizon ......."

It is because the Surveillance system is so unreliable that they need telltale in form of Bomber or ships Nothing to compare

You need to update your information. Try this source on ocean surveillance satellites

US-A

---------- Post added at 01:06 PM ---------- Previous post was at 12:46 PM ----------

Concealing yourself in heavy traffic could go both ways. Amongst those tankers there would always be some Chinese. These captains could radio in if there was a supercarrier on the horizon. I don't think jamming the area would be a viable option at all. It would be a disaster for a trafficked artery if there was no communication. And as Hendrik points out, the most important intelligence ability is to gather information from a range of different sources and put it together.

The downside to this system are the communication links. Any captain of a passing ship would find his and just his communications jammed where he could not get a message out as to what he saw. No need to blanket jam all communications. It is called spot jamming. For more fun you could broadcast false sightings to confuse any system that depends on captains reporting sightings of the carrier and its battlegroup. The Chinese would be forced to spread their forces very thin to respond to all these alleged sightings.

This is for radars, but can apply to any electromagnetic frequency like ship to shore

"....Jamming, in effect, overloads the particular frequency, or frequencies, of the radar. This is an example of 'Spot jamming' pouring all the ECM's power into one frequency, which severely limits that radars ability to detect on that frequency, making all incoming radiation in that range muddled at worst...."

Read more: How does ecm work

Nike this is my last response on this subject. I am bored to death. Russian use nuclear satellite because at that time the solar panel is non existence or have very low efficiency. The soviet never have a robust semiconductor industry to begin with.
Nobody in the world now use nuclear power because it is toxic and heavy. That is why they have such short life 6 month according to this Wiki source. Therefore the need so many launches. Modern satellite last much longer 5 years I guess because they carry more fuel and can keep adjusting their orbit

The Soviet RORSAT program was responsible for orbiting a total of 33 nuclear reactors, 31 of them BES-5 types with a capacity of providing about two kilowatts of power for the radar unit. In addition, in 1987 the Soviets launched two larger TOPAZ nuclear reactors (six kilowatts) in Kosmos satellites (Kosmos 1818 and Kosmos 1867) which were each capable of 6 months of operation.

You keep saying it is impossible to find Carrier in the open sea. Now I would like you to explain it to me how an American satellite company with only 4 optoelectronic satellite can find Varyag knowing only the general area where Varyag is supposed to be. With none of of the accuracy, sophistication or breadth of supporting satellites



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