Formula:

R_Max = ( ( P_t *G* S * A_e ) / ( ( 4 * PI)² * P_Min))

Where,
R_Max = Radar Range
P_t = Transmitted Pulse Peak Power
G = Maximum Power Gain of Antenna
A_e = Antenna Aperture
S = Radar Cross Section Area
P_Min = Minimum Detectable Signal of Receiver

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