China's Anti-Access ASBM Strategy [Defense News]

Now replace frying pan with heat shield, water with ablative material and gas burner with plasma heat due to friction!

It is still hot but get cool enough to allow it to operate . It has been proven combination of shape and ablative material allow space ship to be able to communicate with ground controller.

I don't know how the Chinese actually do it I am not privy to their design. But as long as there is communication they can update the warhead and steer it toward the target. The opfor think they can disrupt the kill chain . But I assume the Chinese know it and built redundancy in their system

Wow how did the discussion get to here.

Really, the frying pan analogy is a wrong one. Here the heat source and water (analogous to the ablative material?) are on the opposite side of a conductive barrier (shield?) whereas in the case of the reentry vehicle the ablative material is heated directly through friction with air molecules and would be blown away as it evaporates. i.e. no chance for the ablative material to form a bubble as would be the case with water on the frying pan. So it's quite possible the ablative material is able to lower down the temperature to below that when the ionized plasma starts to form.

God this thread has gone somewhere. Well l'll keep it going places then.

Quickie said:

whereas in the case of the reentry vehicle the ablative material is heated directly through friction with air molecules and would be blown away as it evaporates

Click to expand...

Not a astrophysicist myself but I've read that "the heat during reentry is a result of air friction" is a common misconception and the heat actually from the air compressing in front of(front as where the capsule is going) the capsule because the capsule is travelling too fast for air to get out of its way.
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I've no idea about why are you guys are talking about ablative materials tho.

AlyxMS said:

God this thread has gone somewhere. Well l'll keep it going places then.



Not a astrophysicist myself but I've read that "the heat during reentry is a result of air friction" is a common misconception and the heat actually from the air compressing in front of(front as where the capsule is going) the capsule because the capsule is travelling too fast for air to get out of its way.
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I've no idea about why are you guys are talking about ablative materials tho.

Click to expand...

Well that is just another way of describing the process since friction always involves the compression of a material or medium which is how heat is generated. The term friction is used as it conveys the idea of an opposite force in the direction of travel.

From Henri K China just built 2nd OVH radar


Satellite images as of December 31, 2016 show that China has begun construction of a second trans-horizon radar (OTH-B), similar to the first that was built in the center of the country and able to locate its Targets over a distance of more than 3,000 km.

For now only the receiver of this second OTH-B radar has been located (a big thank you to our Nix reader who allowed us to find the exact location) right in the middle of the vast prairie of Inner Mongolia, and the works seem Have been initiated less than a year ago.

This receiver is gigantic - in the form of a trapezoid, the two "base" sides are 2.7 and 3.6 km long, and the site that will house the antennas is nearly 500 meters wide. It is thus slightly larger, about 300 meters, than the receiver of the first Chinese OTH-B radar.


Work begins for the receiver site of the second Chinese OTH-B radar (Source: Digital Globe 2016)


The receiver site of the first Chinese OTH-B radar (Source: Digital Globe 2007)

Since the operation of a trans-horizon backscatter radar type (see our article " " for further explanation), the receptor site and that of the transmitter must be distanced from 100 km approximately.

For the moment, no trace of the transmitter's work has been identified with public access satellite images, despite the fact that the site of the transmitter must also be very large, which should measure between 1.6 and 1, 7 km long.

But with reference to the first Chinese trans-horizon radar, where the bodywork of its receiver was completed in June 2007 while that of the transmitter was just beginning at the same time, we should probably wait until mid 2018 to see The site of the transmitter of the second radar. This means that the second Chinese trans-horizon radar will not be operational until 2020 at the earliest.

It also remains to locate the ionospheric measurement stations on the coasts of Bohai Bay and the Shandong Peninsula. These stations are necessary for the proper functioning of this type of radar, they make it possible to control the variation of the ionized layers of the atmosphere (layers F1 and F2 essentially), in order to be able to choose the best short wave propagation frequency to be used by the Radar and therefore get better accuracy.

With the first OTH-B radar, the Chinese built at least 8 ionospheric measurement stations along the east coast of the continent, spread over a distance of over 1,000 km.

As for the area that will be monitored by this new Chinese trans-horizon radar, the orientation of its receiver allows us to make a first estimate on its coverage - Unlike the first Chinese OTH-B radar that targets the wide area between the coast East of China to the second chain of islands, ie to Guam, where the largest US military base is located in the western Pacific, this second trans-horizon radar covered the entire peninsula Korea, and the vast majority of Japan, from Hokkaid île Island in the north to Okinawa Island in the south.

The two Chinese trans-horizon radars would also create a recovery area around the Okinawa archipelago, where the main outlet of the Chinese army to the Pacific Ocean is located.


The coverage (estimate) of the two Chinese trans-horizon radars (Source: East Pendulum)

Although the relatively low resolution of an OTH-B radar, ranging from a few kilometers to ten kilometers depending on the distance from the target, does not provide accurate firing parameters, That it is an effective remote monitoring solution, which especially allows to save a very precise time in early warning on the air and naval targets.

It will not be surprising that a third see a fourth Chinese trans-horizon radar is built in the years to come, to monitor, for example, India and Central Asia.

To be continued.

Henri K.

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Here is the write up on the first OVH radar
From Henri K

The OTH-B radars, which means Over-the-horizon-Backscatter in English, are very long-range radars developed since the 1950s, but actually operable from the 80s to 90s.

The operating principle relies on the reflection of short waves, with a frequency between 3 and 30 MHz, on the ionized layers of the atmosphere such as layers F for example.


Operation of the OTH-B (c) Charly Whiskey

This method avoids the limit of the range of conventional radars due to the curvature of the Earth, the OTH-B radars can thus reach between 800 and 3,500km of range according to the transmission power, the mode of operation (impulse Or continuous wave) and ionospheric quality.

The substantial gain in range is accompanied, in contrast, by less precision, from 8 to 30 kilometers in absolute distance.

Radars of this type also have other physical limitations. For example, in order to obtain sufficient angular precision and to avoid self-pollution of the system, the transmitter and the receiver have to distance themselves by at least one hundred kilometers, which are often often large, Kilometer order.

It is also difficult to obtain the elevation data on the target, although recent methods compensate this with the best processing algorithms.

Finally, it is necessary to measure constantly the variation of the ionized layers of the atmosphere in order to choose the best wave frequencies to be used, and of course to fight any kind of electromagnetic pollution during the activation of the radar along the way.

But despite these constraints, the range of OTH-B radars saves valuable time in early warning, the operating principle also allows them to detect targets at very low altitude, even targets designed to be unobservable in X-band .

OTH-B radars are therefore suitable for long-range surveillance of a large fixed area and angular sector (except for the French NOSTRADAMUS), which the Chinese also call strategic surveillance.



The OTH-B "Project 2319" radar
China began OTH radar pre-studies in the early 1970s. At the time, the work was mainly led by Institute 14 and Institute 22 of the China Electronics Technology Group (CETC).

A first prototype operating in pulse mode and called the " Radar 112-1 " was built in 1982, and he was able to detect commercial aircraft over a distance of 1 000km. The project was awarded the 2nd national prize for scientific progress in 1985.

In 1998, another experimental system operating as a continuous wave was able to detect and track several flying targets at a distance of 2,000 km.

And, if I remember correctly, the first time I heard the official Chinese OTH-B project was in 2007. mentioned the existence of a "brigade Skywave" that would be attached to the army The Chinese air.

The website of the city of Fuqing, which is located on the east coast of China facing Taiwan, published .

After much research, it turns out that Unit 95980 is actually the official reference of this "Skywave Brigade".

From 2009, the university publications are increasing, including , who teaches the construction of a measuring station ionospheric Xia'men, Located at 24 ° 29'N and 118 ° 04'E, as well as its first results of analysis.

This tells us two things - First, there can not be a single vertical measuring station, if we want to be able to accurately map the state of variation of the ionosphere. Then, assuming that these vertical measurement stations are used not only for meteorology but also for the Chinese OTH-B radar, it should be between 800 to 1,000 km from these stations, inside the earth.

But it is difficult to find a transmitter and a receiver, even if they are of kilometer size, over such a large area.

It is in 2010 that me not only on the track of installation locations of the OTH-B radar, but its official name - the Project 2319 .

"会上市保密局局长刘帮成宣读市委保密委员会"关于加强"2319工程"保密工作的规定"市政法委副书记韩辉就驻军社会治安综合治理提出要求,驻军领导对军事保密安全工作明确 明确 意见 意见.

This document gives safety and confidentiality to be observed by the personnel working on Project 2319, and it also mentions the presence of a reservoir or reservoir lake.

These indications helped me to put my hand, finally, on the places where this Chinese OTH-B radar was installed.



The transmitter of the radar is managed by team No. 52 of Unit 95980 and it is located 25km north of the city of Zaoyang. And as stated in the privacy document of the city of Zaoyang quoted above, there is indeed a tank right next to the site of the transmitter.


Project 2319 OTH-B Radar Transmitter

The transmitter site is trapezoid-shaped and measures approximately 1.6km on the longest side.

And since the principle of an OTH-B functioning as a continuous wave forces it, the receiver site is more than 100km from the transmitter, to prevent the emission of waves directly pollute the receivers If the two are too close to one another, given the frequencies used.


Project 2319 OTH-B Radar Receiver

(cont2)

To ensure good angular precision and Azimuth, the receiver site, always trapezoidal, is twice as large as that of the transmitter.

The diagram at the bottom shows the coverage of this Chinese radar of Project 2319, assuming that its range is between 800 and 3,500 km, with an angular coverage of 60 °.



The role and strategic interest in this type of equipment, although very expensive in terms of installation and operation, are well illustrated here. When the conditions of use are favorable, the Chinese can now gain at least 1 hour in early warning time, for the movements that take place between the two chains of islands in the direction of the Pacific of the West.

Note that . I do not know, however, whether it is the signals coming from the 2319 radar in particular.





The ionospheric measurement stations
Because OTH-B radars use the ionosphere as a wave reflector, and its composition varies constantly, it is important to have a clear idea of the quality of these ionized layers in order to be able to choose the best frequency of Propagation and therefore an optimum use. The Chinese have therefore installed vertical measuring stations along its eastern coasts for this purpose.

But if the location of the two sites of radar 2319 was relatively "easy" (I understand ...), that of the ionospheric measurement stations is another sleeve.


XIa'men ionospheric station

Apart from the station of Xia'men, how many are they? Where are they?

In April 2014, an amateur posted a list of Chinese radar units, with 4 measurement stations attached to Project 2319.

This is Team No. 61 in Jiaxing, Team No. 67 in Wenzhou, Team No. xx in Jinjiang, and Team No. 64 in Fuqing. The latter has already been discovered by another source cited above.

But 4 stations would not be sufficient, given the angular coverage of the radar.

It was in October 2014 that , who participated in the 2319 Draft by installing electrical equipment to the sites, we learn that there are actually 8 stations, spread out over more Of 2,000km on the east coast of China.

"The duration of the work was short, and it was necessary to start (works) in all the sites at the same time in the middle of winter," says the text.

It took me several months then to finally locate the 4 other ionospheric measurement stations, after going thru a hundred, if not more, articles and documents R & D.


The 8 ionospheric measurement stations of Project 2319

It is possible to reconstitute the list, certainly not exhaustive, of the different teams, stations and sites of the radar OTH-B of Project 2319 -

Unit Type City District
95980 Headquarter Xiangyang Nanzhang
95980 Team n ° 52 Transmitter Xiangyang Nanzhang
95980 Team # 53 (??) Receiver Xiangyang Zaoyang
95980 Team n ° 61 Ionospheric station Jiaxing Haiyan
95980 Team n ° 63 Ionospheric station Zhangzhou Dongshan
95980 Team n ° 64 Ionospheric station Fuqing Sanshan
95980 Team # 66 Ionospheric station Jinjiang
95980 Team n ° 67 Ionospheric station Wenzhou Wenling
95980 Team n ° 68 Ionospheric station Qidong Huidong
95980 Team n ° xx Ionospheric station Xia'men
95980 Team n ° xx Ionospheric station Ningbo Xiangshan
It should be noted that, Chinese engineers have recently completed a simulation model on the "weather" of the ionosphere. It allows to predict the variation of the ionized layers by zone of 1 ° longitude x 1 ° altitude around China. Chinese television CCTV broadcast a report on the subject.

According to the interview of the head of the national space center, a better prediction of the ionosphere also makes it possible to improve the accuracy of the navigation and positioning system Beidou, as well as the quality of communication provided by the satellites.

If we now put all these installations on the map, we can see that the 8 stations are all inside the zone covered by radar 2319, which confirms well the angular coverage of about 60 ° of the system .




About the Unit 95980
To finish on this article where the technical complexity is not always easy to apprehend (for me in particular), what is known about Unit 95980, which manages all of these installations of Project 2319?

The Unit 95980 seems not to be satisfied solely with the exploitation of the radar but also with the research. Here is the number of scientific publications made by its researchers (??) and the number of citations of their publications (in black) per year since 2006 -



R & D documents are published mainly on 4 Chinese scientific journals - "Radar science and technology", "Modern radar", "Modern defensive technologies" and "Tactical missile technologies".

The subjects of their research vary over time. In 2006, the only publication concerned the design of a radar training simulator. From 2011 to 2012, several documents have been published on time-frequency analysis and de-pollution of signals, as well as methods of maintenance and repair of radar equipment.

And starting in 2014, the effort seems to be focused on the integrated assessment of OTH-B radar performance, model optimization on ground and in-flight targets, an indexing system, and Human Resource Management.

Apart from these elements, the Chinese media speak very little about this subject, certainly because of its sensitive characters. It is only known that it is one of the divisions and brigades that were decorated in 2010 by the Central Military Commission for their excellent training state.

The case to follow.

Henri K.


Annex : A big thank you to my friend , which is an amateur radio warned for dozens of years, to have me explain the need and interest to know the state of the ionized layers of our atmosphere. Here is the extract of his words -

"Very important this ionospheric meteorology. Maps and forecasts are still current.

For some radio frequencies, the high atmospheric layers almost play a mirror role; They allow to return rebound rebound (with the ground) the radio signal to very long distance (intercontinental).

The most convincing case is the short waves which derive their success from this phenomenon. At most the frequency increases at least the radio wave is refracted and therefore carries away.

For frequencies considerably superior to short waves, for example ultra-high frequency (UHF) waves, they pass through these layers of the upper atmosphere without much difficulty and are in fact able to communicate spatially. At the other end it's even better.

Radio-communications technicians always question the state of these upper layers; The quality of the telecom depends very much on it.

As amateur radio, since we all use the radio spectrum, we need to know the quality of these layers ionized by the sun.

The solar cycle (11 years) is monitored closely by the scientific community because the quality of short waves depends on it (scope of radio communications, range of radars, etc.).

The activity of the sun is the motor of the quality of this mirror, hence the numerous sounding rockets (in the northern hemisphere) to study the quality of this mirror layer.

[...] Since the state of the ionized layers of the Earth's highest atmosphere [D, E, F] is indispensable for several reasons in physical science but especially for wave propagation, observation is indispensable and permanent.

This surveillance is similar to that of meteorology, there is a permanent observation and also predictions from models (simulated) more and more relevant; For the ionized layers it is the same, observations like aurora borealis for example, but also prediction with a simulation model. "

I don't know what to make of this picture Hongjian posted on CDF .He is here under different handle name
Supposed to be part of the ship? that get hit by ASBM?

Thanks for the write-ups about China's OTH-B radars. One question: it is acknowledged that China will likely seek to build several more radars to cover all points of the compass, including overlap. At the same time, the existence of a second OTH-B array has only been determined because one of the receive stations was identified by satellite imagery. Does this not therefore suggest that China could already have, or already be working on, several more radars that foreseen for the future, and that these have simply not been identified?

TL;DR: How sure are we that this is in fact China's second OTH-B array, rather than e.g. its fourth?