Coil decoupling for an RF coil array

An RF coil array for use in a magnetic resonance system for detecting MR signals from subject comprising:

• a plurality of separate RF coil elements arranged in an array for receiving RF signals from the subject, each of the coil elements having a conductive loop with a plurality of capacitors and with a pair of ends across one of the capacitors at which the signal is extracted;
• at least one of the separate coil elements having a pre-amplifier circuit for receiving the signal from the pair of ends of the coil element for amplification of the signal to submit to a signal analysis system;
• the pre-amplifier circuit including a transistor and a conditioning circuit in advance of the transistor arranged to determine a required impedance for the pre-amplifier circuit;
• the conditioning circuit element including an inductance;
• said at least one of the coils having a parallel resonant circuit across the pair of ends at said one of the capacitors for generating a high impedance across the pair of ends so as to inhibit coupling in the coil from signals in adjacent, non-adjacent coils and coil elements of the array,
• wherein the parallel resonant circuit is defined by a capacitance including said at least one capacitor and the inductance of the conditioning circuit element of the pre-amplifier circuit;
• and wherein an output impedance of the coil element is arranged to substantially match the required impedance of the pre-amplifier circuit.

An RF coil array for use in a magnetic resonance image system for detecting MR signals from a subject comprising:

• a plurality of separate RF coil elements arranged in an array for receiving RF signals from the subject, each of the coil elements having a conductive loop with a pair of ends across which the signal is applied;
• at least one of the separate coil elements having a pre-amplifier circuit for receiving the signal from the pair of ends of the coil element for amplification of the signal to submit to a signal analysis system;
• the pre-amplifier circuit including a transistor and a conditioning circuit element in advance of the transistor arranged to determine a required impedance for the pre-amplifier circuit, the conditioning circuit element including an inductor;
• said at least one of the coil elements having in the coil elements a first capacitor across which the pair of ends is connected and a second capacitor connected between one of the ends and the input of the pre-amplifier circuit, the first and second capacitors and the inductor from the preamplifier forming components of a parallel resonant circuit for generating a high impedance across the pair of ends so as to inhibit coupling in the coil from signals in adjacent and non-adjacent coil elements of the array coil;
• and wherein an output impedance of the coil element is arranged to substantially match the required impedance of the pre-amplifier circuit.