A computer-controlled broadband system for measuring scattered fields and for locating scattering centers

A number of systematic measuring errors occur when scattered fields are measured with time-harmonic signals. The most important error sources are partly related to antenna cross-talk and multiple reflections between antennas and scatterer. Most procedures for eliminating certain errors are only suited for measurements involving relatively narrow bands. Many procedures are not suited for automatization, and others require a conduction of the measurements in a nonreflecting environment. The present investigation is concerned with a system for measuring scattered fields and for locating scattering centers which is free of the considered disadvantages. The operation of the system is based on the employment of a microwave network analyzer. A description is provided of the design features of the system which make it possible to determine the complex transfer function between transmitting and receiving antennas. Attention is given to the analysis and the elimination of the measuring errors, and the results obtained in the study of three different problems are discussed.