Beacon steering
The Leitstrahllenkung ( engl. Beam riding ) is a method for the control of military missiles by means of a guide beam, which is directed from the launch site of the target. Both radar-based guide beams and laser beams can be used.
Since the missile "rides along" the guide beam during the entire flight, the target lighting is z. B. not possible by a forward observer . There must be no obstacle between the point of launch and the point where the warhead is fired. The method is therefore only suitable for combating targets at short to medium distances. With appropriately equipped missiles, however, it is possible to switch to other steering methods, such as semi-active target guidance , some time after take-off . This method was used, for example, with the RIM-8 Talos .
One advantage of beacon guidance over target lighting or the use of active or semi-active target search guidance is that beam riders do not have to rely on radiation that is reflected from the target and therefore do not have to fly directly to the target. It is also possible to fire with caution or to fight targets that are behind cover.
Radar-based beacon guidance
Radar-based beacon guidance was mainly used in early anti-aircraft missiles . The radar formed a narrow main lobe that was aimed at the target as precisely as possible. The missile now flew along this beacon. Sensors attached to the tail or the tips of the tail unit enabled the missile to determine whether it was still within the radar lobe or was about to leave it. When she left the club, she initiated appropriate course corrections. The flight profile thus resembled a serpentine line, the deflections of which increased over time, as the radar lobe became wider with increasing distance. As a result, the control became more and more imprecise with increasing distance.
One advantage of this guidance system was that an enemy jamming device had to interfere not only with the electronics in the missile itself, but also with the relatively powerful fire control radar.
Systems that used radar beacons included the early versions of the RIM-2 Terrier or the Soviet Kaliningrad K-5 air-to-air missile .
Nowadays this method hardly plays a role and has been almost completely replaced by other methods, such as active or semi-active homing guidance or missiles with infrared seeker heads .
Laser-based guide beam steering
With the availability of lasers , beam steering experienced a renaissance.
Compared to radar-based guide beam steering, the use of a laser has the advantage that the laser beam is very narrow and largely retains its shape even at a greater distance, while the width of a radar guide beam is not only larger from the start, but becomes club-shaped with increasing distance increases. This means that the aiming accuracy is much higher when using a laser.
Since the laser receiver located in the tail of the missile is directly irradiated and does not have to detect the radiation reflected and scattered by the target, as is the case with laser target illumination, a much less sensitive detector or a weaker laser beam is sufficient. The latter makes the beam difficult to detect by a laser warning system that the target may be equipped with.
Laser-based beacons can be used not only to control anti-aircraft missiles, but also anti-tank guided weapons . Examples of missile systems with laser-based beam steering are ADATS from Switzerland, the Swedish RBS 70 or the Soviet or Russian models 9K116 Kastet , 9K119 Refleks and 9K121 Wichr .
Individual evidence
- ↑ Mubarak Al-Jaberi: The vulnerability of laser warning systems against guided weapons based on low power lasers , Cranfield University , January 2006