_ xml_ns="http://www.w3.org/1998/Math/MathML">σ 0 = ⟨ R C S i A i ⟩ {\displaystyle \sigma ^{0}=\left\langle {{RCS_{i}} \over {A_{i}}}\right\rangle }

where:

• RCS_i is the radar cross-section of a particular object, and
• A_i is the area on the ground associated with that object.^[1]

_ xml_ns="http://www.w3.org/1998/Math/MathML">P r = P t G t 4 π r 2 σ 1 4 π r 2 A e f f {\displaystyle P_{r}={{P_{t}G_{t}} \over {4\pi r^{2}}}\sigma {{1} \over {4\pi r^{2}}}A_{\mathrm {eff} }}

where

• _ xml_ns="http://www.w3.org/1998/Math/MathML">P t {\displaystyle P_{t}} = power transmitted by the radar (watts)
• _ xml_ns="http://www.w3.org/1998/Math/MathML">G t {\displaystyle G_{t}} = gain of the radar transmit antenna (dimensionless)
• _ xml_ns="http://www.w3.org/1998/Math/MathML">r {\displaystyle r} = distance from the radar to the target (meters)
• _ xml_ns="http://www.w3.org/1998/Math/MathML">σ {\displaystyle \sigma } = radar cross-section of the target (meters squared)
• _ xml_ns="http://www.w3.org/1998/Math/MathML">A e f f {\displaystyle A_{\mathrm {eff} }} = effective area of the radar receiving antenna (meters squared)
• _ xml_ns="http://www.w3.org/1998/Math/MathML">P r {\displaystyle P_{r}} = power received back from the target by the radar (watts)