Meaning
Biomedical exposure testing utilizes standardized physical models to replicate human interaction with electromagnetic radiation. The SAM phantom provides a consistent, anatomically shaped model of a human head for Specific Absorption Rate measurements of wireless hand-held devices. This hollow plastic shell is filled with a liquid that simulates the electrical properties of human brain tissue.
The application of this model is restricted to testing devices designed for use against the ear, where standardized dimensions ensure repeatable measurements across different laboratories, eliminating variability from varying human head shapes.
Shell Geometry
Anatomical standards define the shape of the physical head model to represent a high percentage of the population. Constructed from a low-loss plastic shell, the SAM phantom features specific positioning points to hold mobile phones in a realistic talk position. This standardized positioning minimizes human error during testing.
Tissue Simulant
Chemical mixtures replicate the dielectric constant and conductivity of human tissue at specific radio frequencies. When using the SAM phantom, the internal liquid must be mixed and verified before testing to ensure it matches regulatory specifications. This calibration is performed at regular intervals to compensate for evaporation.
RF Evaluation
Compliance testing measures the localized power deposition in the simulant during active transmission. Measurements taken with the SAM phantom determine whether the device complies with safety limits for human exposure. This evaluation must be completed before a mobile device can be sold in major markets.
