Distribution Errors in 88 & 1616 Butler-Matrices Multi-Coil Excitation for 7T MRI

Pedram Yazdanbakhsh¹, Klaus Solbach¹

In this abstract, a new method for the measured scattering transmission coefficients of the 88 and 1616 Butler Matrices, used to drive the 8 and 16 coil array in a 7-Tesla MRI system, has been introduced. This method allows for interpretation of amplitude and phase errors in terms of CP-modes, which would be excited in the MRI coil system. Using this method any given distribution of signals at the output ports can be represented as the superposition of an infinite number of CP-modes in the same way as a periodic signal can be represented as a combination of harmonic signals.