Measurement Guideline of Fresnel-Field Antenna Measurement Method

In this letter, a parametric analysis of the Fresnel-field antenna measurement method is performed for a square aperture. As a result, the optimum number of Fresnel fields for one far-field point is guided as Mopt=Nopt=D 2 /λR+5, where D is the antenna diameter, λ is the wavelength, and R is the distance between the source antenna and the antenna under test. For the aperture size 5 ≤ Lx/λ ≤ 20, the tolerable distances for gain errors of 0.5 dB and 0.2 dB can be guided as R0.5 dB ≈ 1.2Lx/λ and R0.2 dB ≈ 2.0Lx/λ, where Lx is the lateral length of the square aperture. The tolerable distances for 20 ≤ Lx/λ ≤ 200 are also proposed. This measurement guideline can be fully utilized when performing the Fresnel-field antenna measurement method.