A Low-Cost Planar Arrow-Shaped Monopole Antenna for 5G Near-Field Measurement

With a diverse range of high-frequency products and devices especially in mm-wave regime, radiation and emission analysis of electronic devices or device-under-test (DUT) are very important to solve electromagnetic compatibility (EMC) problems by using either far-field or near-field scanning measurements [1]–[3]. In a FF measurement system, because FF patterns have to be measured at a point where wave propagations are in the same phase, the FF range can be extended to several meters to tens of meters and that requires a long distance between the antenna under test (AUT) and a probing antenna [4]. In addition, FF measuring approach requires a high cost for isotropic or high gain antennas, big mechanical infrastructure, as well as large-scale measurement chamber areas. In contrast, the NF measurement method employs point-by-point scanning on the surface of the DUT to build a NF scanning data of the DUT [5]. NF analysis requires a small measurement setup environment due to the short distance between AUT and standard scanning probe. Although NF-to-FF transformation and calibration algorithms are required for NF analysis [6] [7], the increase of computational powerful computers effectively helps to solve these algorithms. Therefore, NF measurements in some cases are preferred to FF ones and widely used to estimate the radiation of devices through NF to far field (FF) transformation due to several advantages [4]. NF measurement offers rapid measurement and less engineering labour compared with FF analysis. Additionally, antenna NF measurement offers a reasonable reliability, accuracy and rapid measurements, and small form factor of the measuring mechanical and electrical system.