B1 Mapping and Parallel Excitation using Vector Decoupling
نویسندگان
چکیده
Introduction: Parallel RF excitation is a novel technology that can significantly accelerate multidimensional selective excitation, improve RF homogeneity and reduce SAR. High-fidelity excitation requires accurate knowledge of the transmit array B1 sensitivity profiles and a linear RF transmit system. We present an approach using vector decoupling [1] to facilitate measurement of the B1 sensitivity profiles. The vector-decoupling approach also allows for a simple iterative predistortion of RF system input waveforms to achieve the desired RF currents.
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