Verification and limitations of the monostatic-bistatic radar cross section derived by Kell

Robert Kell developed a relationship between monostatic radar cross section (RCS) and bistatic RCS whereby bistatic RCS can be predicted from monostatic RCS measure under certain conditions. This study found Kell's relationship to be mathematically sound given certain assumptions. Kell's relationship was then tested by comparing computer generated bistatic and monostatic cross sections for simple shapes. Four parameters were varied during testing in order to discern possible limitations of Kell's method: bistatic angle, angle of incidence, electrical size of the target, and continuity. Results of the testing show Kell's method has some merit. The difference between the bistatic RCS and its related monostatic RCS for electrically large spheres is less than 1-dB up to bistatic angles of 80 deg. For electrically large flat and singly curved surfaces the monostatic and bistatic cross sections were within 3-dB for angles of incidence up to 30 deg from broadside and bistatic angles up to 15 deg. Finally, the accuracy of Kell's relationship proved to be polarization dependent when surface discontinuities in the form of 90 deg wedges were present. (RH)