Abstract: A mobile communication system and a usage scenario determination method for the same are provided. The usage scenario determination method comprises: determining a first antenna scenario based on a first impedance measurement on a first transmission antenna; determining a second antenna scenario based on either a second impedance measurement on a second transmission antenna or a sensor information or a receiving antenna tuner states sweeping result; and determining a usage scenario of the mobile communication system based on both the first antenna scenario and the second antenna scenario.

Abstract: A communication system for SAR (Specific Absorption Rate) reduction includes an RF (Radio Frequency), an antenna element, a coupler, and a controller. The RF module provides RF power. The antenna element is excited by the RF module. The coupler is coupled between the RF module and the antenna element. The controller receives antenna information from the coupler. The controller adjusts the level of RF power according to the antenna information.