Advances in PLA C4ISR Capabilities

Publication: China Brief Volume: 10 Issue: 4

C4ISR (Command Control Communication Computer and Intelligence Surveillance Reconnaissance) systems are a key measure of military capability, and an area in which the People’s Liberation Army (PLA) is steadily advancing. Determining how strong PLA capabilities in this area are presents some analytical challenges, as unlike other areas of PLA military growth, C4ISR has received little public exposure. The Chinese military’s ISR systems are more easily surveyed due to the wealth of published imagery, but technical detail on most is scarce and must often be dissected by engineering analysis of antennas or other visual features.

C4 Versus ISR – Analytical Challenges

All modern C4ISR systems can be broadly divided into the "back end" or C4 components, comprising the command and control systems, and the networks and computers supporting them, and "front end" or ISR components, comprising the orbital, airborne, maritime and fixed or mobile ground-based sensor systems, which collect raw data for the "back end" components.

The traditional division of C4ISR systems into strategic, operational and tactical is becoming problematic, as the flexibility of modern digital systems permits many such components to be concurrently employed for all three purposes.

There are good reasons why the PLA has not widely advertised its C4ISR capabilities. The first is that Western, especially U.S. military doctrine, emphasizes early and intensive attacks on an opponent’s C4ISR systems to create confusion and paralysis at a tactical, operational and strategic level. As many C4ISR systems are fixed and difficult to harden, wide public disclosure presents opportunities for opposing intelligence analysis and collection against a critical national vulnerability in times of conflict.

Another consideration is that footage or imagery of racked computer and networking equipment has much less public relations appeal, compared to fighter aircraft, ballistic missiles, guided bombs and other more traditional symbols of national military power.

From a technical analysis perspective, study of C4ISR systems also presents challenges due to the pervasive and usually distributed nature of the technologies used to construct them, the complexity of networked systems, and the now global propensity to share transmission channels, such as satellites, optical fibers, copper cables, and microwave links between civilian and military users, making it difficult to determine where the military capability starts and ends. Often high-quality HUMINT (human intelligence) is the only means of determining the ground truth in such systems.

Airborne and Land Based ISR

The PLA Air Force (PLAAF) has advanced the furthest in atmospheric ISR capabilities, with the development of the KJ-2000 and KJ-200 Airborne Early Warning and Control systems, which like their Western counterparts, fully integrate active radar and passive radiofrequency sensors, with a comprehensive digital and voice C4 system. These airborne systems employ phased array radar technology one full generation ahead of the U.S. E-3C AWACS and E-2C Hawkeye. The C4 fit on either system has not been disclosed. At least four KJ-2000 systems are claimed operational [1].

Reconnaissance pods and internally integrated sensor capabilities in PLAAF strike and multi-role aircraft lag strongly at this time against their Western counterparts. Targeting pods with ISR potential are only now appearing in operational units, mostly for targeting smart munitions.

The PLA has advanced considerably in air defense capabilities, and the C4ISR components have been prominent. Wide and diverse ranges of modern radars of Chinese and Russian origin are progressively displacing legacy Chinese designs. Notable examples are the Russian 64N6E Big Bird battle management radar, used recently in S-300PMU2/SA-20B Gargoyle ATBM trials, and the new Chinese developed Type 120, 305A and 305B high-mobility acquisition radars. These are supplemented by mobile ground-based passive emitter locating systems such as the CETC YLC-20 series [2].

PLA ground forces are now introducing tactical UAVs (Unmanned Aerial Vehicles) to support maneuver force elements, with these displayed prominently during the 60th anniversary parade. While the PLA UAV force is immature by Western standards, considerable effort is being invested to develop this sector. For instance, systems in development or early service include the W-50 fixed wing UAV and Z-3 rotary wing UAV, as well as the CH3 modeled on the U.S. Predator. These supplementary conventional battlefield ISR assets are like the new CAIC WZ-10 reconnaissance and attack helicopter, modeled on U.S. and E.U. equivalents (See "New Advances in PLA Battlefield Aerospace and ISR," China Brief, January 22, 2009).

The established trend to emulate the full spectrum of Western ISR systems is not confined to aerial systems, with two UGVs (Unmanned Ground Vehicles) with ISR potential, the ASENDRO and the CHRYSOR in development (See "New Advances in PLA Battlefield Aerospace and ISR," China Brief, January 22, 2009).

C4 – The Connectivity Challenge

What is less clear is the system-level integration and networking intended for what will become a very modern and diverse fleet of tactical and operational level ISR systems. The latter problem has bedeviled Western military operators for two decades, and definitive technological solutions remain to be found.

China is deploying an extensive grid of terrestrial fiber optic links to support its civil infrastructure, which as noted by various U.S. government reports, provide for a significant dual use capability to support the Chinese military’s C4ISR needs. Buried fiber optic cables provide high bandwidth and are inherently secure from remote SIGINT (signals intelligence), hardened against electromagnetic and radiofrequency weapons and jamming.

PLA thinking on wide operational level connectivity is evidenced by two new systems displayed at the 60th anniversary parade. These are a family of fully mobile tactical satellite terminals, using characteristic dishes with boom feeds, and tropospheric scatter communications systems, easily distinguished by paired dish antennas.

While the PLA’s SATCOM (satellite communication) terminals reflect global trends, the deployment of troposcatter (or tropospheric scatter) communications equipment is much more interesting. The mature U.S. equivalent AN/TRC-170 system was a mainstay of U.S. operational level connectivity during the Desert Storm and Iraqi Freedom Campaigns, providing advancing land forces with high data rate "backbone" connectivity to rear areas.

Troposcatter systems are unique in that they provide non-line-of-sight over the horizon connectivity without the use of a satellite or airborne relay station, this being achieved by bouncing high-power microwave beams off of refractive gradients in the upper atmosphere. As such, a pair of mobile troposcatter terminals can provide multiple Megabits/second data rates to ranges of 100 – 150 miles. The U.S. Army and Marine Corps have employed troposcatter systems for conventional land force long haul data and voice communications applications [3].

The PLA appears to be using troposcatter terminals to support Russian supplied S-300PMU2 and indigenous HQ-9 mobile air defense missile batteries, this permitting a battery to maintain a high data rate channel to any fixed fiber optic terminal within a 150 mile range [4]. As a result, these mobile missile batteries can continuously redeploy in a "shoot and scoot" manner to evade opposing ISR systems, while maintaining connectivity with the centralized fixed air defense C4 system [5]. The wealth of recent high-quality Chinese scientific research papers on advanced troposcatter techniques suggests this technology will become pivotal in PLA C3 operations [6].

There is no direct evidence to date of the troposcatter system being deployed to support mobile Second Artillery Corps (SAC) ballistic and cruise missile batteries (SAC is the strategic missile forces of the PLA). But given that the "shoot and scoot" operating doctrine for these assets differs little from that of air defense missile batteries, the future employment of troposcatter terminals to provide C3 support for SAC units should not come as a surprise if it happens.

Maritime C4ISR Challenges

The PLA Navy has historically relied heavily on its fleet of 1,500 nautical miles range H-6D maritime strike aircraft to provide ISR capability for surface fleet elements, emulating Soviet and NATO Cold War doctrine. This is now changing with the doctrinal shift to the "Second Island Chain" strategy, in which the PLA Navy and Air Force assume responsibility for controlling a much larger geographical area, following an arc from the Marianas, through Northern Australia, to the Andaman Islands [7].

The advent of DF-21 derived ASBMs (Anti-Ship Ballistic Missiles), modern coastal battery deployed cruise missiles like the DH/CJ-10 and C-602, and a range of ASCMs (Anti Ship Cruise Missile) carried by PLA Navy strike aircraft such as the Su-30MK2 Flanker, JH-7 Flounder, and the new turbofan powered H-6K Badger, demands accurate and timely C4ISR support to be effective against opposing maritime forces [8].

To date China’s maritime C4ISR model has emulated Soviet Cold War thinking, reflecting the geo-strategic realities of a continental power seeking to control vulnerable maritime sea-lanes. Unlike the Soviets, however, China’s heavy dependency upon energy and raw materials imports by sea presents an additional vulnerability, more akin to that of the Western powers.

The Soviets initially performed maritime ISR using long range surface search radar equipped Tu-16K Badger C/D and Tu-95RTs/142 Bear D/F long range aircraft, which were equipped with data links to relay maritime surface target coordinates to ASCM armed aircraft, surface combatants, and submarines. As the U.S. Navy increased the reach of its carrier battle group missile and fighter defenses, the Soviets deployed the SMKRITs (Sistema Morskoy Kosmicheskoy Razvedki I Tseleukazaniya / Maritime Space Reconnaissance and Targeting System) RORSATs (Radar Ocean Reconnaissance Satellite), which employed a Molniya satellite communications downlink to relay targeting data to maritime strike assets [9].

China is currently deploying a number of coastal OTH-SW (Over The Horizon Surface Wave) and OTH-B (Over The Horizon Backscatter) radar systems, which provide ISR capabilities against surface shipping systems and aircraft [10]. This technology can provide prodigious detection ranges compared to coastal microwave radars, but is limited by atmospheric conditions, and typically lacks the required accuracy to target a terminally guided weapon, thus providing an effective tripwire ISR capability out to the Second Island Chain, but not the precision targeting capability required to support air and missile strikes.

Implementation of the Second Island Chain strategy will drive the PLA Navy inevitably in the direction of long range UAVs, aircraft and satellites for the provision of targeting ISR, and most likely GeoStationary Earth Orbit (GEO) SATCOM for C3 capability to support aircraft, UAVs and warships performing maritime strike operations.

China’s remote sensing satellite program, characterized by the extant Yaogan-1, -2, -3, -4, and -5, the Haiyang-1B, and the CBERS-2 and -2B satellite systems, have been identified by the Pentagon as dual use capabilities [11]. The planned HJ-1C and HY-3 high resolution radar imaging satellites will have significant potential for RORSAT (Radar Ocean Reconnaissance Satellite) operation, and even if inadequate, will provide the technology base for a future PLA RORSAT constellation [12].

China operates a robust number of foreign built and indigenous GEO satellites for civilian direct broadcast channels, and telecommunications transponder services, including the C-band DFH-3, DFH-4 series. In 2000, the PLA launched the first of the FH-1 series of military SATCOM vehicles, intended as part of the Qu Dian C4ISR system; the latter is described as similar in concept to the NATO/US MIDS/JTIDS/Link-16 and Link-22 systems. In 2008, China launched the Tian Lian-1 data relay satellite, intended to provide expanded communications coverage for orbital assets (Xinhua News Agency, April 25, 2008).

If the PLA exploits existing and developing satellite technology effectively, it will be capable of fielding an effective orbital C4ISR segment to support the Second Island Chain strategy over this decade, including a credible RORSAT capability. Existing dual use capabilities may be improvised to provide a limited near-term capability.

Contemporary Western ISR doctrine sees the penetration of hostile computers and networks as the cyberspace segment of a nation’s ISR capabilities. China’s well-documented, albeit officially denied, activities in penetrating foreign, especially U.S. government, computer systems and networks indicate a strong appreciation of the value of cyberspace as an ISR environment.


In the final analysis, while much of the PLA’s C4ISR capability remains opaque, what is abundantly clear from what is known is that the PLA has an acute understanding of the value of advanced C4ISR in modern conflicts and is investing heavily in this area, emulating specific capabilities and doctrine developed in recent decades in the West and in Russia. Numerous instances demonstrate robust indigenous capability to develop key C4ISR technologies, and apply these technologies in unique and original ways. If the observed trends in PLA C4ISR doctrine and technological capabilities continue unabated, the PLA will have a world-class C4ISR capability in place by the end of the coming decade.


1. Carlo Kopp, The PLA-AF’s Airborne Early Warning & Control Programs, Technical Report APA-TR-2007-07022, Air Power Australia,
2. Carlo Kopp, Almaz-Antey S-300PMU2 Favorit Self Propelled Air Defense System / SA-20 Gargoyle, Technical Report APA-TR-2009-0502, Air Power Australia,
3. Brad E. Rhodes, What is the future of troposcatter in the Army? History, successes, usage and upgrades supporting the Integrated Theater Signal Battalion, Army Communicator, Winter, 2005, U.S. Army Signal Center, Fort Gordon, GA,
4. Kopp, Almaz-Antey S-300PMU2 Favorit Self Propelled Air Defense System / SA-20 Gargoyle, Technical Report APA-TR-2009-0502, op. cit.
5. Ibid.; Carlo Kopp and John Wise, HQ-9 and HQ-12 SAM System Battery Radars, Technical Report APA-TR-2009-1201, Air Power Australia,
6. Hu Maokai, Chen Xihong, Shu Tao, Dong Shaoqiang Missile Inst., AFEU, Sanyuan, China, New generation troposcatter communication based on OFDM modulation, Electronic Measurement & Instruments, 2009. ICEMI ’09. 9th International Conference on, August 16-19, 2009; Shu-xin Chen, Hai-long Gu, Telecommun. Eng. Inst., Air Force Eng. Univ., Xi’an, A detailed simulation study for troposcatter channel, Industrial Informatics, 2008. INDIN 2008. 6th IEEE International Conference on, July 13-16, 2008; and a search of online databases identified 22 recent Chinese language research papers dealing with troposcatter communications theory, available upon request.
7. Military Power of the People’s Republic of China, ANNUAL REPORT TO CONGRESS, 2009, Office of the Secretary of Defense, Washington DC.
8. Mark Stokes, China’s Evolving Conventional Strategic Strike Capability; The anti-ship ballistic missile challenge to U.S. maritime operations in the Western Pacific and beyond, 2049 Institute report, September 2009.
9. Soviet Maritime Reconnaissance, Targeting, Strike and Electronic Combat Aircraft, Technical Report APA-TR-2007-0704,    Air Power Australia,
10. Sean O’Connor, OTH Radar and the ASBM Threat, IMINT & Analysis website,
11. Ibid.
12. Ibid.; Colonel David J. Thompson, USAF and Lieutenant Colonel William R. Morris, USAF, China in Space; Civilian and Military Developments, Air War College Maxwell Paper No. 24, August 2001.