Parametric analysis of NSA data by the methods of piecewise multiple linear regression

NSA data parametric analysis enables us to draw more valuable information concerning quality of a radiated emissions test site. The single breakpoint regression model can best fit either theoretical or measured NSA data because of the nature of ED curves of all NSA geometries. Radiation pattern and phase center should be considered for frequency ranging from 200 to 1000 MHz. In this frequency band a pair of LPDA are used. When distance between the two antennas is 3 meters, the use of hybrid broadband antennas (commonly known as bilog antennas) should be avoided due to their large size. A typical biconical antenna as depicted in MIL-STD-461A has the radiation pattern of a thick dipole. Therefore the CFNSA method is not applicable to the biconical antennas.