Knott’s work details both exact and approximate methods for calculating RCS for various target types: Radar Cross Section - IET Digital Library
Mitigating the massive radar interference that large wind farms cause to nearby air traffic control and weather radar stations.
Understanding Radar Cross Section: A Guide to the Insights of Eugene F. Knott radar cross section eugene f. knott pdf
Eugene F. Knott's "Radar Cross Section" is more than just a book; it is a vital piece of radar engineering literature that has shaped the field for over two decades. Its value to practitioners and students in radar systems, stealth technology, and defense is immense. While a PDF of this essential work can be found online, obtaining a complete, legible, and legal copy is critical.
Angling surfaces to reflect radar energy away from the radar receiver (evident in the sharp facets of the F-117 Nighthawk or the continuous curves of the B-2 Spirit). Knott’s work details both exact and approximate methods
Perfectly smooth shapes are rare. Real-world targets feature edges, corners, and discontinuities. Knott emphasizes that these sharp features act as distinct sources of scattered energy, known as edge diffraction. GTD and PTD provide the mathematical corrections needed to account for energy scattering off the edges of wings, tail fins, and fuselage joints. The Method of Moments (MoM)
Using ray-tracing for large, smooth objects. Knott's "Radar Cross Section" is more than just
σ=limR→∞4πR2|Es|2|Ei|2sigma equals limit over cap R right arrow infinity of 4 pi cap R squared the fraction with numerator the absolute value of cap E sub s end-absolute-value squared and denominator the absolute value of cap E sub i end-absolute-value squared end-fraction : Distance from the radar to the target. Escap E sub s : Scattered electric field strength at the radar. Eicap E sub i : Incident electric field strength hitting the target.
To explore this topic further, look for engineering courses specializing in or reference modern software documentation (like Ansys HFSS or Altair Feko), which still utilize the exact high-frequency asymptotic methods popularized by Eugene F. Knott.
Waves that bind to the skin of the target, travel along its surface, and radiate energy outward when they encounter a discontinuity like a seam or tail joint.
While Knott's text was finalized in the late 20th century, the core physics have not changed. Modern engineers apply Knott's principles to contemporary defense and civilian challenges: