AESA

An Active Electronically Scanned Array (AESA), also known as active phased array radar is a type of radar whose transmitter and receiver functions are composed of numerous small transmit/receive (T/R) modules. AESA radars feature short to instantaneous (millisecond) scanning rates and have a desirable low probability of intercept.
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Agence Européenne de la Sécurité Aérienne (also see the english acronym EASF)
  

ATM END SYSTEM ADDRESS. AESA