HEMP Threats - A Know How

Nuclear explosions in or above the earth’s atmosphere generate an intense electromagnetic pulse (EMP) by the physical phenomenon known as “Compton effect or Compton scattering”. This transient electromagnetic disturbance is called nuclear EMP or NEMP, while a detonation caused at an altitude above 40 km creates a pulse known as high altitude EMP (abbreviated as HEMP). The typical HEMP is defined as a combination of three consecutive pulses called earlytime, intermediate-time, late-time. The effects of the HEMP could lead to an upset or permanent damage of a sensitive electronic system. To take precaution against the effects of the electromagnetic pulse it is important to understand the coupling mechanism of the harmful electromagnetic fields onto RF systems.