Vector Iterative Pre-Distortion: An Auto-calibration Method for Transmit Arrays
نویسندگان
چکیده
INTRODUCTION: Transmit arrays hold growing promise for MRI by enabling improved safety, RF homogeneity, selectivity, and pulse acceleration. Yet achieving good performance with complex Transmit-SENSE pulses [1] requires Tx array channels to be characterized, closely calibrated, and decoupled. To address these needs, we propose Vector Iterative Pre-distortion (VIP), a multichannel iterative correction method which pre-distorts RF amplifier input to achieve desired output at the coil. VIP uses current-sensor feedback from the coil array to detect and correct errors in transmit behavior.
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