Browsing by Author "Shih, Fu-Yuan"

Now showing 1 - 11 of 11

A Fully Integrated Closed-Loop Neuromodulation SoC with Wireless Power and Bidirectional Data Telemetry for Real-Time Human Epileptic Seizure Control
(2017-01-01)
Cheng, Cheng-Hsiang
;
Tsai, Ping-Yuan
;
Yang, Tzu-Yi
;
Cheng, Wan-Hsueh
;
Yen, Ting-Yang
This paper presents a 16-channel closed-loop neuromodulation SoC for human seizure control. The SoC includes a 16-ch signal acquisition unit, a bio-signal processor, a 16-ch adaptive stimulator, and wireless telemetry. The signal acquisition unit achieves 3.78 NEF and shares electrodes with stimulator. The seizure detection latency is 0.76s and delivered 0.5-3mA biphasic current stimulation. The SoC is powered wirelessly and bidirectional data telemetry is realized through the same pair of coils in 13.56MHz.
A simple self-restored fiber Bragg grating (FBG)-based passive sensing ring network
(2009-04-01)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Wang, Chia-Husan
;
Shih, Fu-Yuan
;
Wu, Yu-Fu
In this investigation, we propose and experimentally investigate a simple self-restored fiber Bragg grating (FBG)-based sensor ring system. This proposed multi-ring passive sensing architecture does not require active components in the network. In this experiment, the network survivability and capacity for the multi-point sensor systems are also enhanced. Besides, the tunable laser source (TLS) is adopted in a central office (CO) for FBG sensing. The survivability of an eight-point FBG sensor is examined and analyzed. It is cost effective since the sensing system is entirely centralized in the CO. Experimental results show that the proposed system can enhance the reliability of the FBG sensing network for large-scale and multi-point architecture.
Compensation of power drops in reflective semiconductor optical amplifier-based passive optical network with upstream data rate adjustment
(2011-09-01)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Chiang, Ming-Feng
;
Shih, Fu-Yuan
;
Pan, Ci-Ling
In a wavelength division multiplexed-passive optical network (WDM-PON), different fiber lengths and optical components would introduce different power budgets to different optical networking units (ONUs). Besides, the power decay of the distributed optical carrier from the optical line terminal owing to aging of the optical transmitter could also reduce the injected power into the ONU. In this work, we propose and demonstrate a carrier distributed WDM-PON using a reflective semiconductor optical amplifier-based ONU that can adjust its upstream data rate to accommodate different injected optical powers. The WDM-PON is evaluated at standard-reach (25 km) and long-reach (100 km). Bit-error rate measurements at different injected optical powers and transmission lengths show that by adjusting the upstream data rate of the system (622 Mb/s, 1.25 and 2.5 Gb/s), error-free (<10(-9)) operation can still be achieved when the power budget drops. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3625425]
Experimental demonstration of CW light injection effect in upstream traffic TDM-PON
(2010-06-01)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Wu, Yu-Fu
;
Shih, Fu-Yuan
;
Chi, Sien
High capacity time-division-multiplexed passive optical network (TDM-PON) is an emerging fiber access network that deploys optical access lines between a carrier's central office (CO) and a customer sites. In this investigation, we demonstrate and analyze the continuous wave (CW) upstream effect in TDM-PONs. Besides, we also propose and design a protection apparatus in each optical network unit (ONU) to avoid a CW upstream traffic in TDM-PONs due to sudden external environment change or ONU failure. When an upstream CW injection occurs in TDM access network, the protection scheme can stop the CW effect within a few ms to maintain the entire data traffic. (C) 2010 Elsevier Inc. All rights reserved.
Fiber sensing system with self-detection mechanism
(2010-07-22)
Chow, Chi-Wai
;
Chi, Sien
;
Wang, Chia-Hsuan
;
Shih, Fu-Yuan
;
Yeh, Chein-Hung
The present invention discloses a fiber sensing system with self-detection mechanism which utilizes a central office to control secondary ring architecture formed by fiber sensor, remote node and optical coupler primarily. The secondary ring architecture is connected serially to form a primary ring architecture. The central office has a tunable laser light source that can deliver the light source to the fiber sensor. Since the fiber sensor has reflective ability, all light source signal sent by the tunable laser light source will be detected and measured by the fiber sensor. Thus central office can detect all signals reflected by the fiber sensor and produce a spectrum for analyzing fault point locations. The present invention can greatly enhance survivability and sensing capacity of all fiber sensors, so that when a fault point caused by environmental change within the fiber, it will not effect the overall operation of the sensing mechanism. The application of fiber sensor can also reduce cost and complexity of the overall fiber network topology.
Reliable tree-type passive optical networks with self-restorable apparatus
(2008-03-31)
Yeh, Chien Hung
;
Shih, Fu-Yuan
;
Chang, Gee-Kung
;
Chi, Sien
;
光電工程學系
We propose and investigate a simply self-restored tree-type time-division-multiplexed passive optical network (TDM-PON) with duplex fiber system against the fiber failure. The new proposed optical line terminal (OLT), optical network unit (ONU), and remote node (RN) can be used to prevent and protect the occurrence of fiber failure in the self-protected tree-type PON. The protection and restoration time of the access network can be archived within 7 ms in this experiment. In addition, the performances of data traffic for the fiber access network are also analyzed and discussed. (C) 2007 Optical Society of America.
Tunable Dual-Wavelength Fiber Laser Using Optical-Injection Fabry-Perot Laser
(2008-11-01)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Shih, Fu-Yuan
;
Wang, Chia-Hsuan
;
Wu, Yu-Fu
In this investigation, we propose and experimentally demonstrate a dual-wavelength fiber laser based on a self-injected Fabry-Perot laser diode and an erbium-doped fiber. The dual-wavelength tuning range is 39.49 nm, from 1526.27 to 1565.76 nm. And the mode spacing of the dual-wavelength can be tuned from 1.32 to 39.49 nm. In addition, the output power difference of the dual-wavelength can be controlled and smaller than 1 dB.
Tunable Dual-Wavelength Fiber Laser Using Optical-Injection Fabry-Perot Laser
(2009-01-01)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Shih, Fu-Yuan
;
Wang, Chia-Hsuan
;
Wu, Yu-Fu
In this investigation, we propose and experimentally demonstrate a dual-wavelength fiber laser based on a self-injected Fabry-Perot laser diode and an erbium-doped fiber. The dual-wavelength tuning range is 39.49 run, from 1526.27 to 1565.76 nm, and the mode spacing of the dual-wavelength can be tuned from 1.32 to 39.49 run. In addition, the output power difference of the dual-wavelength can be controlled and smaller than 1 dB.
Using four wavelength-multiplexed self-seeding Fabry-Perot lasers for 10 Gbps upstream traffic in TDM-PON
(2008-11-10)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Wang, Chia-Husan
;
Shih, Fu-Yuan
;
Wu, Yu-Fu
In this paper, we propose and experimentally investigate a simple self-injection Fabry-Perot laser scheme on each optical network unit (ONU) for 10 Gbps TDM passive optical networks (PONs). Based on the proposed four wavelength-multiplexed 2.5 Gbps lasers, the 10 Gbps uplink traffic can be achieved at a cost-effective way. The network architecture and performance have also been analyzed and discussed. (C) 2008 Optical Society of America
Using OOK Modulation for Symmetric 40-Gb/s Long-Reach Time-Sharing Passive Optical Networks
(2010-05-01)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Wang, Chia-Hsuan
;
Wu, Yu-Fu
;
Shih, Fu-Yuan
Due to the requirement of broad bandwidth for next-generation access networks, present passive optical networks (PONs) will be upgraded to 40 Gb/s or higher data rate PONs. Hence, we propose and experimentally demonstrate a simple and efficient scheme to achieve a symmetric 40-Gb/s long-reach (LR) time-division-multiplexed PON by using four wavelength-division-multiplexed 10-Gb/s external on-off keying format channels to serve as the optical transmitter for downstream and upstream traffic simultaneously. Moreover, the system performance of LR transmission and split ratio have also been analyzed and discussed without dispersion compensation.
WDM extended reach passive optical networks using OFDM-QAM
(2008-08-04)
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
Wang, Chia-Hsuan
;
Shih, Fu-Yuan
;
Pan, Ci-Ling
In order to reduce the cost for delivering future broadband services, network operators are inclined to simplify the network architectures by integrating the metro and access networks into a single system. Hence, extended reach passive optical networks (ER-PONs) have been proposed. ER-PON usually has four new features: high data rate in both upstream and downstream signals (> 1 Gb/s); reach extension to > 100 km; a high split ratio (> 100); and using wavelength division multiplexing (WDM). In this work, we propose and demonstrate a highly spectral efficient ER-PON using 4 Gb/s OFDM-QAM for both upstream and downstream signals, while achieving a high split-ratio of 256. The ER-PON employs optical components optimized for GPON (bandwidth of similar to 1GHz) and reaches 100 km without dispersion compensation. Numerical analysis using 16, 64 and 256-QAM OFDM are also performed to study the back-to-back receiver sensitivities and power penalties at different electrical driving ratios. (C) 2008 Optical Society of America.