Alternative Approach of Evaluating 5G Millimeter Waves Phased Arrays Based on Spherical Near Field

5G incorporates millimeter wave (mmWave) range to increase the capability of mobile networks. Accurate and fast measurement methods are required to shorten the cycles in development, testing and production to which today's antenna engineers are devoting. Near field to far field transform (NFTF) is a 3GPP permitted test method for EIRP/TRP of 5G mmWave devices. However, the evaluation of EIRP/TRP for 5G phased arrays transmitting modulated signals is still time-consuming. In this paper, based on spherical near field, the authors present an alternative approach applied to 5G mmWave applications, which can significantly reduce the test time for EIRP/TRP in modulated signals case. The proposed method reuses the EIRP/TRP results in continuous wave (CW) case to facilitate the evaluation of EIRP/TRP in modulated case. The experimental data for a 28 GHz phased array is presented and compared with far-field measurements in detail to illustrate the validation of the proposed method.