A high-order SAR model for multiple transmitters in portable devices

In order to estimate the electromagnetic exposure under multi-antenna transmitters installed in portable devices, a low-order specific absorption rate (SAR) model is generalized to higher orders based on the Fourier series expansion for fast and accurate evaluation and prediction of SAR values as a function of phase differences among multiple transmitters. Numerical and experimental examples are given to demonstrate the effectiveness of the proposed high-order SAR model in LTE communication bands.