Multijurisdictional Co Location SAR Evaluation Limits for Portable Host Devices
Multijurisdictional co-location SAR evaluation requires host-level total exposure ratio analysis and spatial decoupling to ensure global market clearance.
Phantom Liquid Formulations
Meaning
Specialized chemical mixtures simulate the dielectric properties of human tissues for use in radio frequency exposure testing. Different phantom liquid formulations are used to represent specific parts of the anatomy such as the head or trunk. These fluids are essential for ensuring that specific absorption rate measurements are accurate and repeatable across different laboratories.
The electrical characteristics of these liquids are specified by international standards to ensure a uniform test environment for all wireless products.
Dielectric Property
Conductivity and permittivity are the two primary factors that determine how the fluid reacts to radio waves. Each of the phantom liquid formulations must be tuned to match the target frequency band of the device being tested. Regulators provide specific target values and allowed tolerances for these properties to ensure a conservative safety assessment.
Chemical Composition
Typical ingredients include deionized water, salt, sugar and various thickening agents to achieve the desired electrical characteristics. Some phantom liquid formulations use glycols or other solvents to stabilize the mixture over a wider temperature range. The specific recipe depends on the frequency being tested and the standards being followed.
Maintenance Requirement
Fluids must be checked regularly for evaporation or contamination which can alter their dielectric properties. Handling phantom liquid formulations requires care to prevent skin irritation or accidental spills in the laboratory. Periodic testing of the fluid ensures that it remains within the legal specifications for certification work.