The energy absorbed from a handset by the hand is an important issue as it can alter the radiation pattern and cause considerable degradation of phone performance.
Many compromises have to be made in selecting an homogeneous material formulation for a tissue-simulating phantom hand, since real human hands are inhomogeneous exist in a wide range of sizes and can assume an almost limitless range of shapes. An average of IXB hands gives a loss difference of less than 0.7dB (IXB-060) & 0.2dB (IXB-090), from an average of real hands.
The IXB phantom hand shape has been carefully considered and has been configured into the most common setting a real hand may adopt when holding a handset. It has also been sized to allow most standard handsets to be ‘grasped’. For positional repeatability it has been made reasonably ‘stiff’, whilst allowing some flexibility to cater for most DUT’s.
The IXB-060 hands model has been constructed using mesh/polygon, spline NURBS surfaces. Left and right hands are taken from the same model and are mirror images. A solid CAD representation (IGES) is available for the comparison of computational results and measurements.
Positioning accuracy and repeatability are of key importance, and with the unique air spacer/ platform, repeatability +/- 0.1dB has been achieved in OTA tests.