Asymmetric radio frequency coil for magnetic resonance imaging

A radio frequency NMR coil comprising:

• a plurality of conductive elements arranged substantially parallel to one another to define a cylindrical space with some of said plurality of conductive elements having different lengths than other ones of said plurality of conductive elements, and each conductive element has a first end and a second end;
• a conductive first end loop connecting the first end of each of said conductive elements together and having a plurality of first segments each of which extending between two of said conductive elements, wherein each one of a plurality of the first segments includes a capacitor;
• and
• a conductive second end loop connecting the second ends of said conductive elements together and having a plurality of second segments each of which extending between two of said conductive elements, wherein at least one of the second segments being formed by a coaxial cable having a central conductor connected between a pair of conductive elements and other ones of the second segments, which do not have a coaxial cable, including a capacitor with a capacitance which is determined by where a given capacitor is located in the second end loop.

A radio frequency NMR coil comprising a plurality of periodic elements connected in series to form an endless loop, each of said periodic elements including:

• a conductive element having two ends and a given inductance, wherein the inductance for at least some said periodic elements differs substantially from the inductance of other periodic elements;
• a first pair of capacitance elements each having a first terminal connected to one end of the conductive element and a second terminal connected to a capacitance element in another periodic element, and
• a second pair of capacitance elements each having a first terminal connected to another end of the conductive element and a second terminal connected to a capacitance element in another periodic element;
• wherein the first and second pairs of capacitance elements have capacitances determined by the inductance of the conductive element.