The increasingly dominant role being played by electronics in land, sea and air warfare is gradually forcing the world's armed forces to recognize the value of a new concept in tactical operations, often referred to as electronic combat or Electronic Warfare - a significant force multiplier which can often determine the final outcome of a battle. EW has three main branches, namely, Electronic Support Measures, ECM and ECCM. ESM is aimed at providing timely and accurate intelligence of the enemy's communications and other electronic devices to enable decision-making regarding ECM and ECCM methods and policies.
The increasingly dominant role being played by electronics in land, sea and air warfare is gradually forcing the world’s armed forces to recognize the value of a new concept in tactical operations, often referred to as electronic combat or Electronic Warfare (EW) – a significant force multiplier which can often determine the final outcome of a battle. As a result, military tacticians are gradually learning to treat EW assets as an integral part of their overall military capacities when formulating new tactics and doctrine.
The explosive growth in communications electronics and the application of sophisticated micro-electronic technology to weapons systems has revolutionized warfare. Although the general character of war has remained the same, the emerging weapons systems and the Command, Control, Communications and Intelligence (C3I) systems designed to make optimum use of all the assets available to a commander, have undergone numerous evolutionary changes. A wide variety of complex electronics sensors are being employed to observe the battle; computers are required to rapidly process the voluminous amount of information to assist the decision-making process and rapid and secure communications are needed to convey orders almost instantaneously to subordinate formations and units. With this extreme dependence on electronics, the emergence of weapons to exploit or deny the use of the electromagnetic (EM) spectrum is not a surprising development.
From Churchill’s ‘Wizard Warfare’ to ‘War in the Ether’ (that which transmits electronic emissions), EW has emerged as the fourth dimension of warfare, a dimension which is fundamental and decisive on the modern battlefield. The synergetic effect of EW is that of a significant combat force multiplier and a battle-winning weapon of war, if handled with skill and boldness.
Evolution of EW
In every major conflict since the early days of the twentieth century, EW has been practised in one form or another. The first recorded EW attempt was made during the Russo-Japanese war, at the battle of Tsushima in 1905. However, the widespread use of radio for communications began only in the First World War and EW techniques emerged almost simultaneously. The earliest use of EW was limited xo monitoring enemy radio transmissions to gain information. Jamming was done by hit-and-trial methods. The results were spectacular enough to convince even the worst skeptics that a new weapon of war was emerging on the horizon.
During the Second World War, specialized EW equipment was developed, tested and improved to overcome the counter-measures which closely followed each technique. Non-communications equipment such as early warning radars were employed extensively. Passive electronic counter-measures (ECM) in the form of chaff, then known as “windows” consisting of radar reflective aluminium foil strips, and active ECM were not long behind in development. However, conceptually, EW remained a weapon with local influence and very little attention was paid to integrating it and coordinating its employment with tactical operations. At the strategic level, Signals Intelligence (Sigint) played a vital role in every battle from Midway Island to Europe. Sigint greatly abetted Allied victories by ensuring fewer casualties and contributed substantially to bringing the war to an early era. in fact, historians are still evaluating the overall part played by EW in the Second World War and only recently have we become aware of the strategic value of “Ultra” and other such EW projects, as more and more information is being de-classified.
The Korean war saw the development of airborne jamming systems and tail radar warning receivers for fighter aircraft. In 1955, soviet SAM—2 radar-guided missiles brought down an F-4 Phantom aircraft over Vietnam and led to the development of the first dedicated EW aircraft, incorporating jammers and a radar-homing and warning system. In 1971, the North Vietnamese air defences extensively employed heavy barrages of radar-controlled AD guns and SAMs against US B-52 saturation bombing attacks. The US countered by employing extremely sophisticated ECM to bring down their loss rate.
However, it was in the 1973 Arab-Israeli War that EW emerged as a battle-winning factor of undeniable significance. The Arabs’ widespread use of electronics for fire control of AD guns such as the Schilka and SAMs with homing warheads exploiting different bands of the EM spectrum, such as SAM-6 and SAM-7, combined with a full range of ECM and ECCM techniques, almost brought the Israeli Defence force (IDF) to the point of ignominious capitulation. The Israeli Air Force was literally blown out of the skies in the first few days of the conflict. The jamming systems supplied by the US to Israel were designed to cope not with the technology employed by the weapons systems used by the Arabs, but with the more primitive techniques used by the earlier missiles. Poor electronic intelligence (Elint) before the war led to the lack of preparedness of the IDF. But, the [Dr counter-—measures designers staged a splendid recovery and within a few days the Israeli Air Force had regained its traditional mastery over the Arab skies by active and passive counter-measures including evasion based on superior flying skill and tactics. The 1973 war also highlighted the problems of employing a large number of electronics dependent weapons, communications systems and surveillance equipment in limited geographical areas. The use of similar frequencies by both the sides caused severe electromagnetic interference (EMI) and substantially degraded guidance and control systems leading to the shooting down of friendly aircraft.
The dramatic sinking of HMS Sheffield in the Falklands War in 198e has been attributed mainly to the failure of an adequate EW response from the ship to the Argentinian Super Etendard and the Exocet sea-skimming missile which the aircraft launched from a stand-off range. The real story, of course, lies buried with the ship at the bottom of the Atlantic Ocean or deep inside Admiralty files in London. Both in the Falklands War and in the Israeli invasion of Lebanon later that year, EW played a major role in the success achieved by the UK and Israel, respectively. These last three major conflicts catapulted EW to the forefront of modern military thinking. Consequently, all modern armed forces are investing heavily in EW technology. Extremely sophisticated, computer-controlled, automatic EW systems are being rapidly integrated with weapons systems, C3I systems and tactics for the friendly exploitation of EM spectrum and to determine and reduce, prevent or disrupt the enemy’s use of EM waves.
Force multiplier effect of EW
Battlefield dynamics are usually governed by closely interacting functions of combat power and combat imperatives. The four major functions of land combat are manoeuvre, firepower, C3I and combat service support. These are independent and may be said to be points on a continuum. They are the essential ingredients or pillars which make a force a dynamic tactical entity, capable of concerted action on the battlefield. Manoeuvre is the key to success in battle and it is not possible without matching firepower delivered in real-time and coordinated in time and space. C3I provides the vital link which initiates, plans, guides, evaluates, controls and coordinates all aspects of the battle from the preparatory to the execution stage.
Combat service support delivers the indispensable “beans, bullets and bodies” without which an operation cannot be sustained for a period long enough to achieve tactical and operational objectives. The complexity and potentially disastrous vulnerability of equipment and weapons systems and C3I’s preponderant reliance on electronics on the modern battlefield, expose the tenuous links between the four functions of land combat discussed above. Armoured fighting vehicles (AFVs) are entirely dependent on electronics for navigation, fire control and communications. Fire support means, both field and air defence artillery, were among the earliest users of EM energy for mission accomplishment. C3I systems are not only potential BW Objectives during critical phases of the battle, but also excellent sources of real-time combat intelligence for the enemy.
The all-pervasive force or factor, which binds the four pillars together into a cohesive whole which is greater than the sum of its parts, is EW. Without ruling the EM spectrum, a formation commander cannot hope to achieve his goal. ECCM is an essential prerequisite for freedom of action and exploitation of the full combat potential of a force. However, EW is not merely a defensive but a uniquely offensive weapon of war. It can disrupt the functioning of the enemy’s C3I and weapons systems at the time and for the duration that it is necessary to do so, acquire valuable intelligence by monitoring the enemy’s EM transmissions and assist in deceiving the enemy as part of an integrated deception plan.
There is, hence, a need to add EW to the four functions of land combat discussed above. The five functions of land combat can be depicted as the five points of a pentagon. These points are connected internally by a five-cornered star. The figure shows how each of the five is dependent on all the others. EW thus emerges as a force multiplier of immense significance on the modern battlefield, an unseen but deeply felt force whose vast potential is yet to be fully realized.
US and Soviet EW tactics
As in the case of most other newly developed weapons systems and technological breakthroughs, the evolution of modern tactical concepts in EW can be attributed mainly to US and Soviet military thinkers. EW is commonly defined as military action involving the use of EM energy to determine, exploit, reduce or prevent hostile use of the EM spectrum and actions designed to ensure friendly use of the spectrum. EW has three main branches, namely, Electronic Support Measures (ESM), ECM and ECCM. ESM is aimed at providing timely and accurate intelligence of the enemy’s communications and other electronic devices to enable decision-making regarding ECM and ECCM methods and policies. ECM refers to the classic EW attack such as spot, barrage or sweep jamming and radio or radar deception. ECCM techniques enable the friendly use of the EM spectrum without giving away Sigint and with a reasonable degree of freedom from disruption.
In the early stages of the development of EW doctrine, listening to enemy communications, both strategic and tactical in nature, and subsequently determining the location of enemy transmitters, was considered of paramount importance to the overall Sigint activity. The Comint information acquired in this manner was analyzed to estimate the enemy’s tactics and intentions. Jamming was regarded as being detrimental to this intelligence-gathering effort and, as a result, its role was subordinated to that of Sigint. The role of jamming was limited to its selective employment at the tactical level to prevent the enemy from using specific links or from operating freely in certain areas for critical durations.
This approach subsequently evolved in many armed forces into one where the exploitation of enemy transmissions was not considered as important as denying him the use of tactical communications frequencies. This type of communications denial mission usually called for noise jamming in the broad-band mode so as to disrupt several frequency channels simultaneously. Jamming of this type adversely affects own communications, especially in a dense electronic environment. Indiscriminate barrage jamming is known to have disrupted virtually all communications on both sides during the 1973 Arab-Israeli War.
The Soviet approach to EW differs considerably from that of the West. The Soviet concept, termed Radio Electronic Combat (REC), aims to counter an enemy inferior in number but far more dependent on electronics. The Soviets consider their EW assets as part of the overall kill capability of the force. REC tactics involve the use of large-scale barrage jamming in close coordination with suppressive artillery fire to ensure that maximum enemy transmitters in the area of -interest remain out of action for the desired amount of time. The equipment used for this type of REC generally consists of simple detection and direction finding (DF) equipment and high power jammers which are rugged, dependable and effective. Soviet REC tactics are well conceived, suitable for the occasion, run the gamut from inconspicuous to violent, and are methodically executed and fully integrated with the tactical plan.
The US concept is not radically different from the Soviet one in content but varies in emphasis. While US military thinkers agree that there are few occasions when an enemy radar should not be put out of action, through jamming or physical destruction, ideas differ on how to exploit and neutralize enemy communications links. The general tendency appears to be to listen to the traffic, monitor certain links closely and selectively disrupt, deceive and perhaps jam some of these. Physical destruction of communications transmitters is seldom planned as it is prohibitively expensive in terms of resources and of dubious lasting value because of the high degree of redundancy in modern communications systems.
Employment Imperatives of EW Weaponry
Current thinking calls for a much more intelligent and coordinated employment of monitoring, DF and jamming assets by formation commanders. It is now being appreciated that the main aim of communications counter-measures should be to increase communications intelligence while simultaneously trying to hamper enemy operations on the battlefield. The purpose of jamming should not be to deny the use of his communications devices to the enemy but rather to force him to make mistakes and reveal information in his frustrated attempts to communicate. This can be achieved by using short bursts of narrow band or spot jamming against selected channels. In this way key portions of a message can be jammed, forcing the enemy to repeat them several times. this will cause delay and confusion.
In order for such spot jamming to be effective, it needs to be performed in close conjunction with the monitoring and DF functions. Comint data gathered by the latter two functions can be complemented and corroborated by information obtained from the enemy’s confusion and mistakes induced by spot jamming. DF has a vital role to play in making the jamming effective and is a major asset in helping to sort, classify and perhaps identify enemy transmitters in the highly confused dense electronics environment prevailing on the battlefield.
One jamming technique is to transmit narrow band noise signals for very short durations against specific channels or against several channels in a rapid sequence. If this is done systematically over the frequency bands where enemy communications activity has been detected, there is a good probability that parts of messages, whether in spread-spectrum pseudo-random noise, frequency hopping or cryptomode, would be blocked. If this is done using a frequency-agile spot jammer, the enemy may not even be aware that he is being jammed and may attribute disruption to poor equipment performance or bad transmission conditions. This will make him repeat his message and he may start switching between clear and secure modes or between main and alternative frequencies, in a desperate attempt to get his messages through. In NATO exercises, there have been occasions when commanders have mistaken such jamming for faulty encryption devices and have switched over to clear modes of transmission. Besides causing confusion, near panic and considerable delay, this will provide valuable Comint information.
Automated EW weapons systems
With modern communications systems incorporating sophisticated ECCM techniques in their design and using area grid networks with high assurance and redundancy levels, manual EW operations are no longer practically feasible. The requirement is of automated, computer-controlled systems to speed up the intelligence-gathering cycle and to assist in decision-making for a viable and judicious response. Integrated automated EW systems generally perform six basic functions as under:
- Gather tactical and electronic intelligence.
- Exploit the enemy’s communications array.
- Counter new techniques such as the use of encrypted secure speech.
- Speed up the intelligence-gathering cycle.
- Jam at the right time and on the correct cycle.
- Make optimum use of limited numbers of highly skilled personnel.
A typical deployment of an automated EW system at the divisional level comprises an EW operations centre (EW Opcen) with a back-up in the hot stand—by mode, a number of ESM stations, each associated with three or more DF outstations and an ECM station with several dispersed jammers. The EW Opcen and ESM stations are based on central computers. In order to increase redundancy and to reduce access time, the EW data base may be distributed among all cooperating ESM stations and the EW Opcen. Initial analysis is carried out at the ESM stations and the results are relayed to the EW Opcen for more detailed investigation. The EW Opcen may also receive inputs from strategic networks and can synthesize the Comint information with Elint data obtained from other sources to build up an elaborate picture of the enemy’s force structure and dispositions, enabling the signature of his communications array to be determined.
The ESM station carries out the process of search and intercept automatically within the laid down parameters. The tasking of DF outstations for position-fixing of important enemy transmitters can also be automatic with a manual override. The location of a new emitter can typically be found in 10 seconds of its initial detection. The ECM function is similarly controlled but decisions to jam are mostly made by the EW unit commanders in consultation with the General Staff.
The search operator controls his receiver via a VDU and a keyboard. Additionally, he may have a Fast Acquisition Receiver system (FARS) facility to speed up search operations. The FARS comprises a standard receiver, typically covering 20-510 MHz with three antennae for fast automatic search of large frequency bands. FARS can search a 100 MHz band divided into 250 KHz sub-bands with channel width as narrow as 5 KHz in a mere three seconds.
The hardware of automated EW weapons systems is based on state-of-the-art microchips technology and has a very high MTBF (Mean Time Between Failures). The modern concepts of modular design, computerized fault finding and built-in test equipment ensure nominal MTTR (Mean Time To Repair) and almost all repairs can be carried out in the field. Automated EW weapons systems have provided a quantum jump in EW potential to field formation commanders.
EW has added a new dimension to combat on the modern battlefield. Along with C3I, manoeuvre, firepower and combat service support, EW is one of the five functions of land combat. Success in any future battle will depend to a considerable extent on the field formation commander’s ability to skilfully exploit the EM spectrum to his advantage while denying its use to his adversary. The point-counterpoint competition in EW hardware is bound to create more and more sophisticated counter-measures and counter-counter-measures. However, EW concepts will remain essentially the same and the best counter-counter-measure will be to not emit any EM radiations at all.
Communications counter-measures will continue to play a predominant part in the planning and execution of EW missions. Technology and tactics have so evolved that it is no longer essential to ensure total denial of the use of his communications devices to the enemy. On the contrary, it is becoming evident that through the judicious use of jamming, it is possible to obtain more information about the enemy while simultaneously causing him more harm. the long-term value of the intelligence gathered by Comint techniques is likely to be of greater utility than the immediate results achieved by indiscriminate jamming. With all its manifestations of power as a weapon of war on the modern and future battlefield, EW can be considered a true and significant combat force multiplier.