A comparison of measured radar cross section of solid and mesh ogives

An experimental program was conducted in which the radar cross section (RCS) of solid and mesh ogive models was measured and compared. The data covered an ogive length to wavelength ratio varying by a factor of 100. The various ogive models, the measurement ranges employed, and typical data are discussed in detail. Some of the conclusions drawn from the study are as follows. 1) For smooth ogives there is a substantial increase in RCS when part or all of its illuminated surface is replaced by mesh. At higher frequencies, the contribution to the RCS from the illuminated mesh area dominates; that from the shadow side is negligible even in the case of off-axis incidence. 2) The measured on-axis RCS of a mesh ogive exhibits oscillatory behavior about a mean value as the frequency is varied. Furthermore, it is found that this value agrees with that calculated for a rough ogive if the scale of roughness is properly chosen. 3) There is a frequency limit below which the mesh ogive RCS is identical to that of a solid ogive. At this frequency, the mesh opening along the axial geodesic direction is no larger than
0.03\lambda
.