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The signal amplification by reversible exchange (SABRE) technique is a very promising method for increasing magnetic resonance (MR) signals. SABRE can play a particularly large role in studies with a low or ultralow magnetic field because they suffer from a low signal-to-noise ratio. In this work, we conducted real-time superconducting quantum interference device (SQUID)-based nuclear magnetic resonance (NMR)/magnetic resonance imaging (MRI) studies in a microtesla-range magnetic field using the SABRE technique after designing a bubble-separated phantom. A maximum enhancement of 2658 for 1 H was obtained for pyridine in the SABRE-NMR experiment. A clear SABRE-enhanced MR image of the bubble-separated phantom, in which the para-hydrogen gas was bubbling at only the margin, was successfully obtained at 34.3 μT. The results show that SABRE can be successfully incorporated into an ultralow-field MRI system, which enables new SQUID-based MRI applications. SABRE can shorten the MRI operation time by more than 6 orders of magnitude and establish a firm basis for future low-field MRI applications.

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Radio reception relies on the medium which determines the propagation characteristics of the electromagnetic fields carrying the information. The permittivity varies greatly depending on the medium, but it remains nearly constant, except when magnetic materials are used. For this reason, magnetic fields, typically affected by permeability, can be utilized in microwave challenging environments. In this paper, a new approach based on the giant magnetoimpedance (GMI) effect is presented. The proposed GMI-based receiver has an effective double-superheterodyne topology, where "effective" means that the receiver actually has a single mixer but appears to have added a virtual mixer due to the GMI effect. The magnetic field-tovoltage conversion ratio (MVCR), the spurious free dynamic range (SFDR) and the receiver sensitivity are characterized, and from these results the optimal operating conditions of the fabricated receiver are obtained. Additionally, wireless digital communication using on-off keying (OOK) is demonstrated and transmitted and received waveforms are compared, with the final demodulation result of the receiver showing that the transmitted digital data are precisely extracted.

In this paper, we present motivation, system concept, and implementation details of stereoscopic 3D visual services on T-DMB. We have developed two types of 3D visual service : one is '3D video service', which provides 3D depth feeling for a video program by sending left and right view video streams, and the other is '3D data service', which provides presentation of 3D objects overlaid on top of 2D video program. We have developed several highly efficient and sophisticated transmission schemes for the delivery of 3D visual data in order to meet the system requirements such as(1) minimization of bitrate overhead to comply with the strict constraint of T-DMB channel bandwidth; (2) backward and forward compatibility with existing T-DMB; (3) maximize the eye-catching effect of 3D visual representation while reducing eye fatigue. We found that, in contrast to conventional way of providing a stereo version of a program as a whole, the proposed scheme can lead to variety of efficient and effective 3D visual services which can be adapted to many business models.

This paper presents a new application field of a giant magneto-impedance (GMI) sensor. It shows valuable findings for the GMI sensor on the possibility of a new receiving element in magnetic field communication. The proposed GMI sensors serve as antennas and mixers in receiver systems. They have the advantage of being easily implemented and in terms of mass production and manufacturing processes due to the manufacture base on a printed circuit board (PCB). Their smaller size, lower cost, and higher sensitivity have more advantages than conventional magnetic sensors, such as the magneto-inductive, anisotropic magneto-resistive, and giant magneto-resistive sensors. Two types of PCB-based GMI sensors are proposed. The first type of GMI sensor is directly wound around the solenoid-shaped pickup coil onto an alumina insulation tube inserted with an amorphous microwire. The second type of GMI sensor has a patterned pickup coil that does not require the winding of the coil, similar to the patterned pickup coil of a micro electro-mechanical system-based GMI sensor. This GMI sensor provides a new geometry that can be easily manufactured with two PCB substrates. The proposed GMI sensors achieve the equivalent magnetic noise spectral density to the high-sensitivity characteristics of the pT/√Hz level. The equivalent magnetic noise spectral density of 1.5 pT/√Hz at 20.03 MHz is obtained for the first type of GMI sensor, and 3 pT/√Hz at 3.03 MHz is achieved the second type. The analyzed results of the bandwidth and the channel capacity for the two types of GMI sensors are acceptable. This first analysis confirms the possibility of the implementation of GMI sensors in magnetic field communication. The results of this experiment confirm the high performance of the proposed GMI sensors and their applicability in magnetic field communication. The detailed experimental results of the proposed GMI sensors are presented and discussed. INDEX TERMS Amorphous microwire, giant magneto-impedance (GMI), high sensitivity, magnetic field communication, magnetic sensor.

In this article, we propose a time-sequential switching light-field (LF) camera for an alternative image capture of the high-resolution two-dimensional (2-D) images and three-dimensional (3-D) LF elemental images as additional functionalities. For image data acquisitions of both the 2-D and 3-D LF imaging of moving objects at a video frame rate (or even higher frame rate up to approximately 1000 f/s), a polarization-dependent-switching microlens array (MLA) is implemented in the LF camera system instead of a conventional passive-type MLA. By controlling the incident polarization conditions using an electrically fast-switching liquid crystal layer, the imaging mode can be time-sequentially switched quite rapidly (switching times of approximately 220 and 290 µs for the mode conversions from the 3-D LF to the 2-D mode, and the reversal mode change, respectively). Using the elemental image sets sampled from the alternating time-sequential imaging results, either the directional-view images or depthrefocused images can be reconstructed and provided at a moving picture frame rate. The depth-refocused images

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