CST – Computer Simulation Technology

Predicting SAR Behavior using Spherical Phantom Models

Due to the fact that measurements in true biological heads typically cannot be carried out, SAR norms for mobile phones or EMI problems are commonly defined in terms of standardized phantom models. In the easiest case, only spherical structures are considered. To predict the SAR behavior of a new product already during the design stage, it is desirable to include the phantom head in the EM simulations.

The following examples investigate two spherical phantom models, a basic one that only contains of tissue material inside a glass sphere and a more complex one that has two additional layers of bone and tissue.  A dipole antenna is used for the excitation and is displayed as a yellow line in the following picture: 



Figure 1: Basic spherical phantom head containing tissue meterial in glas. The yellow lines represent the exciting dipole antenna....


The SAR distribution is simulated at 835 MHz and visualized in the figure below. A comparison of the SAR values over a radial line shows good agreement with the measurement of the same structure.



Figure 2: SAR values in a 2D cutplane inside the phantom model.



Figure 3: Comparison of simulation and measuremant results along the orange arrow in the previous figure.

For the following simulation a more complex model including a simplified skull is used.



Figure 4: Inhomogeneous phantom model including a simplified skull.

A comparison of the SAR values at 1.95 GHz on an off-axis path shows a significant difference between the basic homogeneous model and the more complex one. Since the values are higher, the simplified model may not be sufficient in all cases.



Figure 5: Comparison of the SAR values at 1.95 GHz for the basic and the inhomogeneous model.

Rate this Article

0 of 5 Stars
5 Stars
0%
4 Stars
0%
3 Stars
0%
2 Stars
0%
1 Stars
0%
contact support

Your session has expired. Redirecting you to the login page...

We use cookie to operate this website, improve its usability, personalize your experience, and track visits. By continuing to use this site, you are consenting to use of cookies. You have the possibility to manage the parameters and choose whether to accept certain cookies while on the site. For more information, please read our updated privacy policy


Cookie Management

When you browse our website, cookies are enabled by default and data may be read or stored locally on your device. You can set your preferences below:


Functional cookies

These cookies enable additional functionality like saving preferences, allowing social interactions and analyzing usage for site optimization.


Advertising cookies

These cookies enable us and third parties to serve ads that are relevant to your interests.