Byunghun Lee

A triple-loop wireless power transmission (WPT) system equipped with closed-loop global power control, adaptive transmitter (Tx) resonance compensation (TRC), and automatic receiver (Rx) resonance tuning (ART) is presented. This system not only opposes coupling and load variations but also compensates for changes in the environment surrounding the inductive link to enhance power transfer efficiency (PTE) in applications such as implantable medical devices (IMDs). The Tx was built around a commer

Abstract A new study with rat sciatic nerve model for peripheral nerve interfacing is presented using a fully-implanted inductively-powered recording and stimulation system in a wirelessly-powered standard homecage that allows animal subjects move freely within the homecage. The Wireless Implantable Neural Recording and Stimulation (WINeRS) system offers 32-channel peripheral nerve recording and 4-channel current-controlled stimulation capabilities in a 3 × 1.5 × 0.5 cm 3 package. A bi-direction

An inductively-powered wireless integrated neural recording and stimulation (WINeRS-8) system-on-a-chip (SoC) that is compatible with the EnerCage-HC2 for wireless/battery-less operation has been presented for neuroscience experiments on freely behaving animals. WINeRS-8 includes a 32-ch recording analog front end, a 4-ch current-controlled stimulator, and a 434 MHz on - off keying data link to an external software- defined radio wideband receiver (Rx). The headstage also has a bluetooth low ene

A platform has been presented for wireless powering of receivers (Rx's) that are arbitrarily distributed over a large area. A potential application could be powering of small Rx implants, distributed over large areas of the brain. The transmitter (Tx) consists of three overlapping layers of hexagonal planar spiral coils (hex-PSC) that are horizontally shifted to provide the strongest and most homogeneous electromagnetic flux coverage. The three-layer hex-PSC array is driven by a three-phase time

In modern implantable medical devices (IMDs), wireless data transmission between inside and outside of the body is essential to control IMD parameters and report the acquired data to the external part of the system. Unlike conventional far-field data communication, which is more suitable for free space, near-field data transfer techniques have been widely adopted for transcutaneous data links in IMDs. These data links should be designed for robustness against misalignments and interference, whil

A wirelessly powered homecage system, called the EnerCage-HC, that is equipped with multicoil wireless power transfer, closed-loop power control, optical behavioral tracking, and a graphic user interface is presented for longitudinal electrophysiology and behavioral neuroscience experiments. The EnerCage-HC system can wirelessly power a mobile unit attached to a small animal subject and also track its behavior in real-time as it is housed inside a standard homecage. The EnerCage-HC system is equ

This paper presents a new method, called multicycle Q-modulation,to modulate the quality factor (Q) of the receiver (Rx) coil and dynamically optimize the load impedance to maximize the power transfer efficiency (PTE) in two-coil links. A key advantage of the proposed method is that it can be easily implemented using off-the-shelf components without requiring fast switching at or above the carrier frequency, which is more suitable for integrated circuit design. Moreover, the proposed technique d

In this paper, a new LED fluorescent driver compatible with a rapid-start ballast is proposed. Using a compensation circuit composed of passive elements, a new LED fluorescent driver having highly reliable and robust characteristics was developed. This driver can prevent the fire problem that arose in conventional LED fluorescent switching power supplies. The design principle and architecture of the proposed LED driver was explained, and its feasibility was confirmed by simulations and experimen

An adaptive averaging low noise analog frontend (AFE) is presented for central and peripheral nerve recording applications. The proposed topology allows users to trade off, on the fly, between input referred noise and the number of channels via averaging. The new low noise amplifier (LNA) utilizes a complementary doubled input transconductance (g <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> ) topology to effectively increase the noise eff

A robust wireless power transfer system, containing primary and secondary coils, for a humanoid robot is proposed in this paper. Multiple primary coils constitute a `Power mattress' structure on the ground, and a few secondary coils constitute a `Power shoe' of a humanoid robot. When the foot wearing the power shoe is on the power mattress, a strong magnetic linkage is built up between the shoe and mattress; so wireless power is transferred through resonated circuits. When the foot is away from

This paper presents a small, low-cost self-regulated rectifier for parallel-resonant receivers (Rxs) in the wireless power transmission (WPT) system to maintain the individual rectifier voltages of each Rx to be constant. The problem of the conventional rectifier-low-dropout regulator (LDO) for parallel-resonant Rx coil is analyzed. Specifically, although the LDO attempts to reduce the excessive voltage by increasing its dropout resistance, this increases the power delivered to the Rx coil and r

When it is necessary to detect various physiological signals of the human body, clothing embroidered with near-field effect patterns can be used as a long-term power supply medium to supply power to long-distance transmitters and receivers to form a wireless power supply system. The proposed system uses an optimized parallel circuit to achieve a power transfer efficiency of more than five times higher than that of the existing series circuit. The power transfer efficiency of simultaneously suppl

In modern implantable medical devices (IMDs), wireless power transmission (WPT) between inside and outside of the animal body is essential to power the IMD. Unlike conventional WPT, which transmits the wireless power only between fixed Tx and Rx coils, the wirelessly-powered cage system can wirelessly power the IMD implanted in a small animal subject while the animal freely moves inside the cage during the experiment. A few wirelessly-powered cage systems have been developed to either directly p

REITs(Real Estate Investment Trusts) which have introduced since July, 2001 have triggered investment in real estates. Initially, office buildings were in the spotlight. However, after introducing Indirected Real Estate Fund in 2004, the attention of investment target has varied greatly from shopping malls and hotels to residential facilities. However, office buildings are still the favorite investment sector in terms of stability and profits, and it consists approximately 46% of REITs. In this