Single, Depolarized, CW Supercontinuum-Based Wavelength-Division-Multiplexed Passive Optical Network Architecture With C-Band OLT, L-Band ONU, and U-Band Monitoring

We propose and experimentally demonstrate a novel bidirectional wavelength-division-multiplexed passive optical network architecture that fully utilizes the superior optical properties of an incoherent continuous-wave (CW) supercontinuum (SC) source. The proposed architecture, which incorporates low-cost Fabry-Perot laser diodes that have been wavelength locked by spectrum-sliced beams from a depolarized 130-nm-bandwidth CW SC source, is based on a unique wavelength band allocation scheme of the C-band for an optical line terminal (OLT), the L-band for optical network units (ONUs), and the U-band for channel monitoring. A cost-effective network that features a single broadband source at the OLT, and no additional wavelength- band-selective monitoring beam reflector at each ONU can be readily achieved. The experimental demonstration presented in this paper is carried out at a data rate of 622 Mb/s over a 25-km standard single-mode fiber.     

Detection of laryngeal function using speech andelectroglottographic data

The purpose of this research was to develop quantitative measures for the assessment of laryngeal function using speech and electroglottographic (EGG) data. We developed two procedures for the detection of laryngeal pathology: 1) a spectral distortion measure using pitch synchronous and asynchronous methods with linear predictive coding (LPC) vectors and vector quantization (VQ) and 2) analysis of the EGG signal using time interval and amplitude difference measures. The VQ procedure was conjectured to offer the possibility of circumventing the need to estimate the glottal volume velocity wave-form by inverse filtering techniques. The EGG procedure was to evaluate data that was "nearly" a direct measure of vocal fold vibratory motion and thus was conjectured to offer the potential for providing an excellent assessment of laryngeal function. A threshold based procedure gave 75.9 and 69.0% probability of pathological detection using procedures 1) and 2), respectively, for 29 patients with pathological voices and 52 normal subjects. The false alarm probability was 9.6% for the normal subjects.     

RuO2/GaN Schottky contact formation with superiorforward and reverse characteristics

This is a first time report of a ruthenium oxide (RuO₂) Schottky contact on GaN. RuO₂ and Pt Schottky diodes were fabricated and their characteristics compared. When the RuO₂ Schottky contact was annealed at 500°C for 30 min, the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of the RuO₂ were dramatically improved. The annealed RuO₂ /GaN Schottky contact exhibited a reverse leakage current that was at least two or three orders lower in magnitude than that of the Pt/GaN contact along with a very large barrier height of 1.46 eV, which is the highest value ever reported for a GaN Schottky system     

Inverted Staggered Poly-Si Thin-Film Transistor With Planarized SOG Gate Insulator

In this letter, we have studied the inverted staggered thin-film transistor (TFT) using a spin-on-glass (SOG) gate insulator and a low-temperature polycrystalline silicon (poly-Si) by Ni-mediated crystallization of amorphous silicon. The p-channel poly-Si TFT exhibited a field-effect mobility of 48.2 cm²/V ldr s, a threshold voltage of -4.2 V, a gate-voltage swing of 1.2 V/dec, and a minimum off-current of < 4 times 10^-13A/ mum at V_ds = -0.1 V. Therefore, the gate planarization technology by SOG can be applicable to low-cost large-area poly-Si active-matrix displays.     

A new approach to cell size scaling with a multi-dual cell and a buffer/background programming of unified RAM

New investigations are presented here on a high-density and DRAM-like high-speed non-volatile memory (NVM) application of unified RAM (URAM). For a high-density application of URAM, multiple data storage is demonstrated with a multi-dual cell (MDC). Because each NVM state can be split by programming with a one-transistor (1T) DRAM without a capacitor, the total number of memory states can be doubled. Furthermore, a high-speed DRAM-level NVM scheme is proposed for the joint operation of 1T DRAM buffer programming and NVM post-background programming. The MDC and the proposed scheme are unique URAM properties that can extend the application range of memory devices.     

Modeling and Simulation of New Encoding Schemes for High‐Speed UHF RFID Communication

In this paper, we present novel high‐speed transmission schemes for high‐speed ultra‐high frequency (UHF) radio‐frequency identification communication. For high‐speed communication, tags communicate with a reader using a high‐speed Miller (HS‐Miller) encoding and multiple antennas, and a reader communicates with tags using extended pulse‐interval encoding (E‐PIE). E‐PIE can provide up to a two‐fold faster data rate than conventional pulse‐interval encoding. Using HS‐Miller encoding and orthogonal multiplexing techniques, tags can achieve a two‐ to three‐fold faster data rate than Miller encoding without degrading the demodulation performance at a reader. To verify the proposed transmission scheme, the MATLAB/Simulink model for high‐speed backscatter based on an HS‐Miller modulated subcarrier has been designed and simulated. The simulation results show that the proposed transmission scheme can achieve more than a 3 dB higher BER performance in comparison to a Miller modulated subcarrier.     

A tele-monitoring system for gait rehabilitation with an inertial measurement unit and a shoe-type ground reaction force sensor

In this paper, a tele-monitoring system is proposed, using an inertial measurement unit (IMU) and a shoe-type ground reaction force (GRF) sensor called a Smart Shoe to measure a patient’s walking data, and transmitting the measured data via the Internet. In our previous work, a mobile gait-monitoring system was developed, which provided visual feedback based on GRFs measured by a Smart Shoe (used as a mobile platform). However, the limited information provided by the Smart Shoe alone may not be adequate for a tele-monitoring system using the Internet. In the present tele-monitoring system for gait rehabilitation, a Smart Shoe is combined with an IMU for detailed monitoring of walking motions. By analyzing the signals from the IMU and the Smart Shoe, foot trajectories, walking distance, length of stride, etc., can be estimated. A user-friendly graphic interface displays the measured or estimated data on separate computers at the patient’s location and the physical therapist’s office. Thus, using the proposed system, it is possible to monitor a patient’s walking motion via the Internet, without restrictions on time or place.     

Analysis of a Parasitic‐Diode‐Triggered Electrostatic Discharge Protection Circuit for 12 V Applications

In this paper, an electrostatic discharge (ESD) protection circuit is designed for use as a 12 V power clamp by using a parasitic‐diode‐triggered silicon controlled rectifier. The breakdown voltage and trigger voltage (V_t) of the proposed ESD protection circuit are improved by varying the length between the n‐well and the p‐well, and by adding n+/p+ floating regions. Moreover, the holding voltage (V_h) is improved by using segmented technology. The proposed circuit was fabricated using a 0.18‐μm bipolar‐CMOS‐DMOS process with a width of 100 μm. The electrical characteristics and robustness of the proposed ESD circuit were analyzed using transmission line pulse measurements and an ESD pulse generator. The electrical characteristics of the proposed circuit were also analyzed at high temperature (300 K to 500 K) to verify thermal performance. After optimization, the V_t of the proposed circuit increased from 14 V to 27.8 V, and V_h increased from 5.3 V to 13.6 V. The proposed circuit exhibited good robustness characteristics, enduring human‐body‐model surges at 7.4 kV and machine‐model surges at 450 V.     

A Liquid Metal Based Multimodal Sensor and Haptic Feedback Device for Thermal and Tactile Sensation Generation in Virtual Reality

Virtual reality (VR) has been widely used for training, gaming, and entertainment, and the value of VR is continually increasing as a contact-free technology. For an immersive VR experience, measuring finger movements and providing appropriate feedback to the hand are as important as visual information, given the necessity of the hands for activities in daily life. Thus, a hand-worn VR device with motion sensors and haptic feedback is desirable. In this paper, a multimodal sensing and feedback glove is developed with soft, stretchable, lightweight, and compact sensor and heater sheets manufactured by direct ink writing (DIW) of liquid metal, eutectic gallium-indium (eGaIn). In the sensor sheet, ten sensors and three vibrators are embedded to measure finger movements and provide vibro-haptic feedback. The other heater sheet provides thermo-haptic sensation in accurate and rapid manner via model-based feedback control even under stretched conditions. The multimodal sensing and feedback glove allows users to feel the contact status and discriminate materials with different temperature. Performance of the proposed multimodal glove is verified under VR environments including touching and pushing two blocks of different materials and grabbing a heated metal ball submerged in hot water.