Eight-channel phased array RF coils design for 3T parallel MRI system

Magnetic Resonance Imaging (MRI) is one of well-known imaging modalities because it is noninvasive, does not produce ionization and offers various contrast mechanisms for all kinds of tissues, especially soft tissues. Faster image acquisition is indispensable in current imaging technology, especially for dynamic object. Parallel MRI (pMRI) offers such possibility to faster acquire the reconstructed image by using several receiver coils with varying spatial sensitivity instead of a single coil with homogeneous sensitivity. This paper proposes a rotary phased array head coil owing to the phased array coil advantages for rapid imaging with parallel processing and reducing image artifact due to its larger field of view. The proposed array coils consist of eight independently single-coil, where each single-coil is made from some pieces of conductors onto which directly connected each other with twelve capacitors so thus the resonant frequency can be tuned precisely at 128 MHz for 3T MRI system. Each coil is circularly-arrayed and sequentially-activated to form a volume RF coil in order to achieve relatively homogeneous H-fields. The numerical results show good reflection coefficient at 128 MHz and relatively uniform H-field strength distribution. Moreover, the specific absorption rate (SAR) is relatively low inside the head phantom model up to 50W of input power.