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.
Portable Host Devices
Meaning
End products such as laptops, tablets and handheld scanners provide the primary interface for wireless communication modules. These portable host devices determine the final position and orientation of the internal antennas relative to the human body. The physical characteristics of the enclosure directly influence the electromagnetic emission profile of the integrated radio.
Manufacturers must evaluate the combination of the radio and the host to ensure the final product is safe for the end user.
Physical Form
Design choices regarding materials and size dictate where the internal components can be placed. In many portable host devices the limited internal volume forces antennas to be located near the edges or behind plastic windows. The choice between a metal or plastic chassis significantly changes the way radio frequency energy is distributed.
Power Management
Battery life and thermal constraints often limit the maximum output of the integrated wireless transmitters. Some portable host devices use proximity sensors to reduce the radio frequency power when the user is nearby. This dynamic adjustment helps the product meet safety requirements without sacrificing performance at a distance.
Certification Requirement
Testing the complete assembly is necessary to confirm that the combination of the radio and the enclosure is safe. For portable host devices the manufacturer must provide detailed documentation on how the modules are integrated and what shielding is used. A change in the host design often requires a new round of compliance testing.