HIGHLIGHTS

• Defining and discussing ECM and ECCM

• Developing the basic relationships in mainlobe jamming

• Expanding to the sidelobe jamming case

• Sidelobe canceling, concepts of adaptivity

• The low probability of intercept (LPI) radar and radar warning receivers (RWRs)

• Active ECM techniques and their counter-countermeasures

• Passive ECM techniques and their counter-countermeasures

Because radar finds and measures noncooperative targets, it motivates various countering actions. Motorists might want to deprive the highway patrolman of information about their speed. Certainly, nations want to deny other nations all kinds of information, particularly in times of tension or war. An obvious way of denying radar information is to disrupt the very small amounts of received target signal with spurious energy either actively, by radiating energy in the radar s frequency band (called jamming or active ECM), or passively, by dispensing various extraneous objects (called passive ECM). Both classes of ECM are aimed at obscuring the target or confusing or misdirecting the radar or its operator. In the United States military, a culture has arisen that is based on the development of ECM and responses to it (called electronic counter-countermeasures, ECCM). All types of electronic transmissions, not just radar, are involved. An international professional society, called the Association of Old Crows (AOC), thrives.

Because the fate of nations may depend on the effectiveness of ECM and ECCM, details related to specific hardware are highly classified. Yet, there is a great deal of literature available on ECM and ECCM...