Implementation and characterization of MIMO RF navigators towards robust TR-by-TR head motion sensing

Motivation: Motion is among the most common sources of artifacts in MRI. RF navigators address this challenge by providing a powerful and sensitive method for contact-free motion sensing. Goal(s): This work seeks to evaluate the motion sensitivity of RF navigators towards optimizing their use for head motion sensing. Approach: In this work we characterize a multi-input multi-output system for head motion sensing using pilot tone and beat pilot tone. Results: The frequency-sensitivity of beat pilot tone was evaluated and an optimal transmission frequency was identified for head motion sensing. The impact of artifacts due to vibration is investigate Impact: We present and characterize the first system for multiple-input multiple-output (MIMO) RF motion sensing with BPT and PT, aimed toward head motion sensing and correction at arbitrary frequencies, and simultaneous to the MRI exam.