Sensor Improvements Facilitated by Evermore Processing Power
“New and Evolving Threats” is a term that has been with us for decades and is in common use to create a need and justify upgrades to systems, weapons and sensors often at a not insignificant cost. We do see “new” threats, it is true, and by and large, they evolve in a never ending technological race to outwit counter strategies. However, it could be argued, that many threats thought of as “new” are no more than an evolution of what has come before and that the real menace is the ever increasing pace of this evolution driven by the exponential growth in processing power. For those involved in defence and military planning, the future potential threats can seem overwhelming as traditional sensors and counter measures struggle to keep up.
However, not only do we now have to cope with the increased complexity this processing capability provides our foes, we also have to accept that the buffer in technological superiority that historically offset our numerical inferiority has, to all intents and purposes, disappeared and we now face the unfortunate reality of potential “peer” engagements.
It is refreshing, therefore, that in the radar sphere, the West still maintains an edge and we continue to innovate and (we hope!) keep ahead of potential adversaries by harnessing that same increase in processing power to achieve significant capability improvements.
In the air defence arena, for example, the vulnerability of radar has always been an issue due to the priority attached to its destruction. EMCON policy aside, measures to increase survivability include mobility coupled with short set-up and set-down times. Additional layered defence techniques around the unit are also of benefit. Finally, separating the user from the sensor probably does little to equipment survivability but at least enhances the life expectancy of the operators. However, there is little “new” about all these techniques and while the radar itself has become ever more capable, the evolution of techniques to hide the radar from the enemy is only now starting to gather pace.
At the core of this change is Passive radar – itself a slow developer having evolved at a snail’s pace since its introduction in the Second World War. Its first deployment immediately showed one of its core benefits. Until overrun by advancing troops, its existence was successfully kept secret. It remains a virtually undetectable technology due to the relatively small antenna and the absence of any transmission from the equipment itself. Modern processing power has now enabled the technology to rival the performance of more conventional radars.
HENSOLDT’s TwinVis Passive Radar
The ability of a single antenna to silently create an air picture out to over 200 kilometres with an update rate of less than a second is truly remarkable. Even more so when one considers current stealth technology is rendered obsolete by the absence of the need for a signal to be returned to its source and by the fact the system operates in frequency bands not normally associated with military radars.
A Screenshot of Southern German Airspace Captured by HENSOLDT’s TwinVis Passive Radar
Almost impervious to jamming, the system uses state of the art processing and high-end computing platforms to deliver real-time tracking and situational awareness. This is achieved by analysing the electromagnetic spectrum in both VHF and UHF bands to “see” anomalies and accurately deduce the presence of targets.
Accurate enough to be considered by some authorities as an Air Traffic Control back up system, TwInvis offers an effective, relatively inexpensive, air surveillance radar with significant war fighting advantages. The accuracy can be sufficient to engage targets. It is therefore possible to destroy an incoming threat without any active transmission from the ground at all, thereby significantly increasing the survivability of a Ground-Based Air Defence (GBAD) unit. Alternatively, when integrated with an AESA radar, the 3D target data from the passive radar could be used to direct a single beam to lock on and hold the target and avoid the need for wider, more detectable transmissions. With both sensors deployed in tandem any subsequent radar countermeasures by the pilot are unlikely to deceive.
GBAD Units Such as the TRML-4D Increase Survivability When Complemented by TwinVis Passive Radar
In the coming years, any GBAD unit without a passive radar will be seen to be at an unnecessary disadvantage and the relatively low cost of the units should see widespread deployment in NATO and aligned countries.
On a slightly different tack, another radar evolution made possible by increased processing power, is the ability to counter drones. Drones are no longer “new” but their proliferation and utilisation of evolving technology make them an ever-increasing threat. For radars, there are two main aspects to consider. Firstly, the radar needs to be sensitive enough to detect small targets at significant ranges but this very capability introduces the second problem. Small drones and birds have similar radar cross sections. It is not unusual for a radar in Europe to be seeing 600 or more birds an hour which in turn creates a false alarm rate that is an impossible burden for an operator to manage. Therefore, the increased radar sensitivity has to go hand in hand with techniques to automatically classify targets so that the system can dispense with the operator and be able to autonomously warn of drones in the vicinity. Again, the processing power now available makes this capability possible.
HENSOLDT’s SPEXER Radar Autonomously Differentiates Between Birds and Drones with Over 99% Accuracy
Once detected, the next step depends on the location and situation. Effective drone countermeasures used above a crowded stadium are clearly going to be different to those used on the battlefield. A thrill seeker flying a cheap drone above a crowded stadium armed with little more than a bag of harmless flour could cause pandemonium if jammer countermeasures resulted in a loss of control. In the stadium vicinity therefore, more sophisticated counter measures are required to safely neutralise the threat. In this case, the miniaturisation of electronics and the increased processing power enable a drone to be despatched that can intercept the intruding drone, deploy a capture net and return with its cargo to safety – all without user intervention.
The HENSOLDT VADR Capture Drone in Action
The above example illustrates how the evolving threat of drones is not straightforward to counter and there is no one single approach that will be appropriate in all scenarios. This is equally true of the radar sensor. A stadium can be protected by a radar detecting drones at little more than a kilometre whereas on the battlefield, the required detection ranges are much more demanding. Some uses will dictate 360 degree coverage while for others, a single non-rotating flat panel will suffice. Some scenarios only require 2D detection while others demand a 3D picture. To cover the multitude of requirements, we need a family of radars like the HENSOLDT SPEXER range to provide the appropriate performance and coverage and keep within the end users’ budgets. Only a decade or so ago, radars with these capabilities would have been prohibitively expensive but the ever increasing processing power and miniaturisation of components available to designers enables more and more capable radars to be available at a much lower cost.
HENSOLDT UK SPEXER 600 2D AESA Radar – Affordable AESA Technology
To conclude, new and evolving threats keeping defence planners awake at night are a concern but the technology enabling advances in adversaries’ weapons and systems is also enabling a wave of innovative developments in the West to provide effective counter measures. While the technological gap is not as large as we would like or as large as it was in the past, there remain areas where we continue to offer significant advantages over equipment likely to be fielded by a future foe.
HENSOLDT UK, formerly known as Kelvin Hughes, boasts a long tradition of capable and reliable radars. As part of the HENSOLDT group, the company offers a range of ground-based radars. While the history of radars spans more than 100 years, it is characterised by countless innovations, many of which stem from HENSOLDT. One recent milestone is HENSOLDT’s TwInvis passive radar system mentioned above.
“HENSOLDT offers an impressive portfolio of complementary radar sensors and systems for the Land domain, all of which are fully supportable here in the UK. Based in Enfield, North London, HENSOLDT UK designs and manufactures a number of these radars, as well as providing programme management, system integration and through life support for the entire range. These are exciting times for our business, as HENSOLDT invests further in its UK capabilities in support of a number of MOD programmes.”
Rohan Dearlove – Sales Director UK and Ireland