Active radar seeker, data-link or IR?
The ability to deny the availability of satellite based navigation systems, like GPS, and data links within a conflict area is becoming easier and easier to obtain. Today, relatively unsophisticated adversaries can obtain and operate basic Electronic Warfare (EW) equipment that presents an operational threat to units relying on GPS and data-links.
Some countries have already launched programs aimed at finding technologies that can supplement GPS for that very reason. Against a sophisticated adversary, weapons will need to be able to operate autonomously and be insensitive to powerful EW that disables or disrupts not only GPS, but other communication channels as well.
According to Miguel Svensson, Director Business Management for Saabs anti-ship missile system RBS15, one main reason to use an active radar target seeker is the size of the target seeker area.
“Since signal attenuation due to absorption by the atmosphere is much lower for radar than other wavelengths, its range is much greater than for example, an IR sensor. This allows for detection and acquisition of targets moving at high speed at long ranges, without requiring target position updates via a data link or relying on GPS positioning”, says Miguel.
The active radar target seeker used by the RBS15 missile is powerful enough to overwhelm potential jammers. Its transmissions are also unpredictable in frequency and time, making it difficult for the adversary to effectively target the jamming. These and other features allow the RBS15 to counter most existing forms of active and passive electronic countermeasures.
“One of the many tricks the RBS15 has up its sleeve is a Home-On-Jam feature. This means that under specific circumstances and for several types of jamming, the missile can home in on the source of the interference, effectively turning it into an anti-radiation missile. This places the adversary in a difficult position; forced to either stop jamming and see the missile find its target, or continue jamming and allow itself to become the target”, says Miguel Svensson.
The target seeker also has a unique target discrimination capability thanks to the high resolution in both bearing and range which also contributes to discrimination and suppression of false signals from chaff, decoys and jammers. Additionally, the target seeker’s functionality is software defined. This allows the missile to easily adapt to new threats as they emerge and for new features to be added through software updates.