𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Multiple tuning of birdcage resonators

✍ Scribed by Smain Amari; Aziz Müfit Uluǧ; Jens Bornemann; Peter C. M. Van Zijl; Peter B. Barker


Publisher
John Wiley and Sons
Year
1997
Tongue
English
Weight
764 KB
Volume
37
Category
Article
ISSN
0740-3194

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

A theoretical framework is presented for designing birdcage resonators for MRI and MR spectroscopy. The analogy between the birdcage problem and the phonon problem in solid‐state physics is used to achieve multiple tuning. Allowing that the capacitances in the columns of the cage assume unequal values, it is possible to achieve multiple tuning and simultaneously preserve the sinusoidal current distribution necessary to set a homogeneous magnetic field. Given the physical dimensions of the columns and branches of the cage as well as the desired resonant frequencies, the corresponding values of the capacitances can be calculated exactly. Closed‐form expressions for the capacitances are given in terms of the mutual inductances and the desired resonant frequencies. A detailed analysis for a symmetrical low‐pass birdcage is presented. The expressions for the resonant frequencies reduce to those given by other authors when only nearestneighbor mutual inductances are included.


📜 SIMILAR VOLUMES


Resonant Modes of the Birdcage Coil
✍ Mark C. Leifer 📂 Article 📅 1997 🏛 Elsevier Science 🌐 English ⚖ 191 KB

This paper presents a small and complete set of analytic equalength show that the model calculations can usefully predict tions which can be used to design a birdcage coil and predict its birdcage performance, can aid in choosing dimensions and resonant modes a priori before construction begins. The

Radiative losses of a birdcage resonator
✍ Michael D. Harpen 📂 Article 📅 1993 🏛 John Wiley and Sons 🌐 English ⚖ 290 KB

## Abstract We present a derivation of the losses in a birdcage resonator due to radiation. We also present an expression for the radiation limited Q. It is shown that in head coil imaging at 63 MHz radiative losses may account for 20% of the total loss with a radiation limited Q on the order of 15

Experimental design and fabrication of b
✍ Thomas Vullo; Raymond T. Zipagan; Romeo Pascone; Joseph P. Whalen; Patrick T. Ca 📂 Article 📅 1992 🏛 John Wiley and Sons 🌐 English ⚖ 503 KB

## Abstract Although the birdcage resonator has been theoretically described for single‐ and multinuclear operation, this study provides the basic experimental guidelines needed for the fabrication and testing of such coils for various geometries and resonant frequencies from 10 to 95 MHz. The corr

Tuning effect analysis of cylindrical di
✍ Yinchao Chen; Qunsheng Cao; Kunquan Sun; Benjamin Beker; Raj Mittra 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 289 KB

## In this article we analyze the resonant characteristics of cylindrical dielectric-loaded resonators based on a two-dimensional cylin-( ) drical finite-difference᎐time-domain method 2D-CFDTD . First, we ¨alidate our approach by comparing the computed data for a specified structure with that a¨ai

Experimentally verified, theoretical des
✍ Gary X. Shen; J.F. Wu; Fernando E. Boada; Keith R. Thulborn 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 260 KB 👁 2 views

A new theoretical method is presented for designing frequency responses of double-tuned, low-pass birdcage coils. This method is based on Kirchhoff's equations through a nonsymmetric matrix algorithm and extended through a modification of the corresponding eigenvalue system from a single-tuned mode.