With the goal of producing larger working regions of uniform irradiance and phase in microwave anechoic chambers, we have built a disassemblable, tapered chamber in which to study the effects of (a) source size and (b) source position. Recognizing that the long walls of tapered anechoic chambers are partially reflecting mirrors, we have developed an elementary theory for optical design of chambers, and made computations that agree with microwave experiments. To design wider plateaus of irradiance in the working region, we have used computer programs for the interference patterns produced by the primary source and the multiple-image virtual sources.
ROBERT O. DELL, CLINTON R. CARPENTER, and C. L. ANDREWS, "Optical Design of Anechoic Chambers," J. Opt. Soc. Am. 62, 902-906 (1972)