Spectrum Signature Modeling and Data Reduction Techniques Applicable to Airborne Antennas

Information is presented on a modeling technique and on data reduction techniques applicable to obtaining the spectrum signatures of low-gain, low-frequency airborne antennas. The modeling technique demonstrates the degree of simplicity permissible in the fabrication of aircraft scale models on which test antennas are mounted. It is shown that simple geometric shapes employed to represent an aerodynamically shaped aircraft will yield sufficiently accurate information for antenna signature evaluation, thus allowing far-field antenna characteristics to be obtained at a relatively low cost. A brief discussion of an analog-digital converter unit is also included. This unit is employed in the placing of antenna pattern data in a format that is applicable to the Electromagnetic Compatibility Analysis Center (ECAC) computer facilities.