Pseudo-Isotropic Source for Anechoic Chamber Qualification
Perry F. Wilson, John M. Ladbury, Galen H. Koepke
A pseudo-isotropic source is presented. The source consists of an electrically-large cavity with internal excitation (horn antenna), a variable internal boundary condition (a rotating paddle as in a reverberation chamber), and randomly placed apertures for external radiation. On average, the radiation pattern approaches that of an isotropic source. Data are presented for a non-optimized box realization showing +/- 3 dB isotropy over typical planar cuts. Simulation suggest that better than +/- 2 dB should be possible.