Definition of Far Field Measurement Distance for 5G mmW Antenna Arrays: Application on N × M Patch Arrays

The purpose of this paper is to define a mathematical formulation for patch arrays Far Field (FF) distance allowing to calculate the FF distance from the array size (N×M), the operation frequency and substrate permittivity. It illustrates how the theoretical FF distance based on the antenna dimension and wavelength overestimate the practical FF distance by 5 times.