There is provided an RF (radio frequency) coil assembly of a magnetic resonance imaging (MRI) system, which comprises a birdcage transmit-only coil using inhomogeneous modes. Further, a multi-channel receive-only phased array coil is provided. In one embodiment, the multi-channel receive-only phased array coil may include a plurality of ring-shaped receive-only coils, wherein the receive-only coils are connected to each other in a pseudo-chain-link configuration to form a ring shape. The multi-channel receive-only phased array coil may be located inside said transmit-only coil and spaced a predetermined distance apart therefrom. In accordance with the embodiments, emphasis images of the peripheral part of a human brain with high resolution and high signal to noise ratio may be obtained.