David Otto Brunner1, Jan Paska2, Juerg Froehlich2, Klaas Paul Pruessmann1
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland; 2Laboratory for Electromagnetic Fields and Microwave Electronics, ETH Zurich, Zurich, Switzerland
The SAR assessment from electromagnetic field simulation is a crucial step in safety validation of RF transmission systems. In the case of parallel excitation using transmit arrays this task is more intriguing since the distribution of the SAR deposition can vary significantly with changing field superposition of the elements in the array. In this work we present a method leading to a rigorous closed form calculation of worst case SAR deposition and optimum array performance with respect to local SAR deposition in the entire body. These evaluations can be used to set system power limitations and transmit array benchmarking respectively.