Efficient remote transmission line probe tuning.

An approach is described which allows remote tuning of a probe via a length of transmission line, while retaining nearly ideal efficiency relative to the equivalent locally tuned coil. This preservation of efficiency is accomplished through the principle of "partial local matching." In comparison to common methods of remote tuning which involve half-wavelength cables, or in which a length of transmission line is itself utilized as a tuning element, the partial matching method results in a substantial increase in the efficiency of power transfer to the coil, and therefore increased B1 field intensity and signal-to-noise ratio. Applications in which the use of local variable tuning capacitors is made difficult by either space, accessibility, or environmental considerations should benefit from this method.