title: Application of the planar-scanning technique to the near-field dosimetry of millimeter-wave radiators.
abstract: The planar-scanning technique was applied to the experimental measurement of the electric field and power flux density (PFD) in the exposure area close to the millimeter-wave (MMW) radiator. In the near-field region, the field and PFD were calculated from the plane-wave spectrum of the field sampled on a scan plane far from the radiator. The measurement resolution was improved by reducing the spatial interval between the field samples to a fraction of half the wavelength and implementing multiple iterations of the fast Fourier transform. With the reference to the results from the numerical calculation, an experimental evaluation of the planar-scanning measurement was made for a 50 GHz radiator. Placing the probe 1 to 3 wavelengths from the aperture of the radiator, the direct measurement gave the near-field data with significant differences from the numerical results. The planar-scanning measurement placed the probe 9 wavelengths away from the aperture and effectively reduced the maximum and averaged differences in the near-field data by 70.6% and 65.5%, respectively. Applied to the dosimetry of an open-ended waveguide and a choke ring antenna for 60 GHz exposure, the technique proved useful to the measurement of the PFD in the near-field exposure area of MMW radiators.
authors: School of Electronic Engineering, Xidian University, Xi'an, China.
authors: Jianxun
authors: J
authors: Zhao
authors: Hongmin
authors: H
authors: Lu
authors: Jun
authors: J
authors: Deng
mesh_terms: D060733:Electromagnetic Radiation; D004867:Equipment Design; D008962:Models, Theoretical; D011874:Radiometry / Q000295:instrumentation / Q000379:methods*
keywords: choke ring antenna; electric field exposure; open-ended waveguide; power density