Study On Several Key Problems For Planar Near-field Scattering Measurements

NearfieId scattering measurement ranks among one of the moSt prondsingmethods for radarcross-secton (RCS) measurementS of comPlex mptS. Severalkey problems are discussed in mis papeL Fbet, the producing of quiet-zone ofWtic plane wavs (SPW) are calculatal, wth various window fhactions, which have strong influences on the shape and size of quiet-zone. Second, the near-filed to far-field transform formula is deduced to obtain the echo-width of a target from the near-field scattering fields. A right circular cylinder target demonstrates its validity, where the large- bistatic and small-bi static near-field scattering measurements are executed. Third, the near-field scattering measurement, where the transmitting and receiving probes scan on the same plane, is discussed with several targets under test (TUT), with the focus being placed on the reliable-angle-range (RAR). An effective region concept is introduced to present the reliable-angle-range. Fourth, the near-field scattering measurement can be regarded as a multi-port microwave network, therefor a scattering parameter matrix can represent it. The lack of strip problem is solved by the aid of interpolation methods. Finally, based on the high frequency scattering center concept, a model is set up to represent the self-transmitting-and-receiving scattering measurement (STSR or STAR), which is used to deduce the procedure of near-field scattering measurement. And the measuring time required is reduced greatly in the light of this method. The theoretical results and measured ones are in good agreement.