Spherical mm-Wave Anechoic Chamber for Accurate Far-Field Radiation Pattern Measurements

In order to measure different types of millimeter-wave antennas for 5G and 6G antenna applications, such as planar, 3D, on-chip or in-package, the anechoic chamber must have certain features. In this article, we describe a newly designed and realized spherical anechoic chamber. With a mechanically complex design for the integrated probe-station, RF -extender holder and reference antenna, an attempt has been made to create an anechoic chamber that is as functional and ideal as possible, whereby the aforementioned variety of antennas can be characterized with minimal influence of the setup. This chamber design strategy has been validated by measuring a radiation pattern from a standard gain horn and an end-fire antenna array in the frequency band from 26.5 GHz to 40 GHz. The measurement results are compared with the simulation results, where the deviation is below 0.5 dB for the half-power beamwidth for the horn antenna and below 1 dB for the half-power beamwidth and first side-lobe level of the end-fire antenna array.