T/R Switches, Baluns, and Detuning Elements in MRI RF coils

نویسندگان

  • Xiaoyu Yang
  • Tsinghua Zheng
  • Hiroyuki Fujita
چکیده

T/R switches, baluns and detuning elements are three major devices to reduce RF/EM couplings among receive RF coils, transmit RF coils and MRI system environment around RF coils in MRI system. Inadequate designs on these parts often lead to unnecessary high transmit power consumption, noisy NMR signal and the RF heating issues. In this paper we discuss the basic functions, theories and commonly used types of these three devices. Figure 1 shows a diagram of typical transmit/receive coil with these devices.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Assessment of the Characteristics of MRI Coils in Terms of RF Non-Homogeneity Using Routine Spin Echo Sequences

Introduction: One of the major causes of image non-uniformity in MRI is due to the existence of  non-homogeneity in RF receive and transmit. This can be the most effective source of error in  quantitative  studies  in  MRI  imaging.  Part  of  this  non-homogeneity  demonstrates  the  characteristics of RF coil and part of it is due to the interaction of RF field with the material being  imaged...

متن کامل

Micro-Electromechanical Systems (MEMS) based RF-switches in MRI – a performance study

Modern Magnetic Resonance Imaging (MRI) systems permit parallel, spatial-encoded MRI (pMRI) and as such it is now possible to have up to 128 adjacent coil elements in a coil array [1]. Together with reduced imaging times, pMRI can significantly help to enhance the signal to noise ratio (SNR) over extended fields of view (FOV) [2]. However, a large number of channels subsequently create new tech...

متن کامل

3-D RF Coil Design Considerations for MRI

High-frequency coils are widely used in medical applications, such as Magnetic Resonance Imaging (MRI) systems. A typical medical MRI includes a local radio frequency transmit/receive coil. This coil is designed for maximum energy transfer or wave transfer through magnetic resonance. Mutual inductance is a dynamic parameter that determines the energy quantity to be transferred wirelessly by ele...

متن کامل

Non-uniformity of Clinical Head, Head and Neck, and Body Coils in Magnetic Resonance Imaging (MRI)

Introduction Signal intensity uniformity in a magnetic resonance (MR) image indicates how well the MR imaging (MRI) system represents an object. One of the major sources of image non-uniformity in high-field MRI scanners is inhomogeneity of radio-frequency coil. The aim of this study was to investigate non-uniformity in head, head and neck, and body coils and compare the obtained results to det...

متن کامل

Reconfigurable Antenna Aperture with Optically Controlled GeTe-Based RF Switches

We have characterized the ON state DC electrical resistivity and OFF state capacitance of GeTeBased RF Switches under direct optical laser excitation. Our tightly-coupled dipole array exhibits performance in excess of 4 to 1 bandwidth over wide-scan angle up to 60 degrees with in-band rejection capability using reconfigurable baluns. Integration of optically-controlled GeTe-Based RF switches at...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2006