This example shows the Specific Absorption Rate (SAR) calculation of the EN 50361 SAM Phantom head (SAM = "Specific Anthropomorphic Mannequin"). The head is modeled by a shell filled with a liquid which represents the average material properties of the head. The advantage of this model is that it approximates real-life laboratory measurements. For more complex human biological models, CST MICROWAVE STUDIO® (CMS) also offers a Voxel Import Interface for user-defined biological tissues and the HUGO Dataset for the standard human model.
The phantom head model is imported via CST MWS's SAT Interface. The working plane is set to the left hand side of the head in order to define a simple cell phone model. The phone consists of two primitives, a brick and a cylinder. The excitation is defined using a discrete port between the two components....
For the SAR calulcations, power loss monitors should be defined at the frequencies of interest. In this example, a monitor was set at 900 MHz. Farfield monitors may also be defined in order to investigate the effect of the presence of the head on the farfield characteristic of the antenna.
Figure 2 shows one of many possible field plots that may be chosen to display the SAR results. Field contours can be displayed on slices or so-called cutplanes through the model. Further post-processing of the results is possible as well as the facility to export field values at points, on planes or within volumes.
The SAR calculation dialog and results window are shown in Figure 3. The SAR calues may be either globally averaged or local values defined over a volume specified by the user.
CST MWS is ideal for applications such as the simulation of biological tissues with mobile phones or medical equipment. More complex mobile phone or devices may be imported via the wide-range of import formats such as SAT, STEP, IGES, DXF and many others.