amsar active phased array radar aerostat bae systems integrated system technologies dassault rafale digital effective radiated power electronic countermeasures elta ericsson eurofighter typhoon europe euroradar captor field of view gtdar german navy helicopter hydraulics klystron main lobe northrop grumman passive electronically scanned array phased array phazotron radar raytheon sampson sachsen class frigate silicon tikhomirov scientific research institute of instrument design transmitter