Browsing by Author "Lai"

Now showing 1 - 8 of 8

Apparatus of multi-stage network for iterative decoding and method thereof
(2010-05-25)
Wong
;
Cheng-Chi
;
Lee
;
Yung-Yu
;
Lai
An apparatus and method of multi-stage network for iterative network are disclosed. The apparatus has M stages, and each stage uses N multiplexers to transmit N codeword partitions simultaneously. Every starting terminal, either the output port of memories, soft-in soft-out decoders, or multiplexers, has two paths to couple with two different multiplexers at next stage. One path connects the source to the first data port of one multiplexer; the other connects the source to the second data port of another multiplexer. The two multiplexers will be controlled with the same 1-bit signal, so each source has only one valid path to next stage. The invention can guarantee that the transmission of N data blocks is free from contention.
Evanescent-field optical amplifiers and lasers
(2007-02-27)
Chen
;
Nan-Kuang
;
Chi
;
Sien
;
Tseng
An optical amplifier and a laser generator based on the fiber side-polished technology having a high pumping efficiency, a low noise figure and a small footprint are provided in this application. The optical amplifier and the laser, which have a very long effective interaction length in conjunction with highly doped Erbium glass attached to its surface and an addition of a slanted fiber grating inscribed in the guiding core at the polished region can spatially separate the signal and pump power to simultaneously improve the pumping efficiency and optimize the penetrated depth of the signal evanescent-field. The spontaneous emission is kept from being amplified and therefore a high quality amplified signal is produced.
Evanescent-field optical amplifiers and lasers
(2007-01-30)
Chen
;
Nan-Kuang
;
Chi
;
Sien
;
Tseng
An optical amplifier and a laser generator based on the fiber side-polished technology, having a high pumping efficiency, a low noise figure and a small footprint are provided in this application. The optical amplifier and the laser, which have a very long effective interaction length in conjunction with highly doped Erbium glass attached to its surface and an addition of a slanted fiber grating inscribed in the guiding core at the polished region can spatially separate the signal and pump power to simultaneously improve the pumping efficiency and optimize the penetrated depth of the signal evanescent-field. The spontaneous emission is kept from being amplified and therefore a high quality amplified signal is produced.
Fabrication of true apodized fiber Bragg grating using a new two-beam interferometer with polarization control
(2005-11-08)
Chuang
;
Kai-Ping
;
Sheu
;
Lih-Gen
;
Tsai
The present invention provides a two-beam interference exposure system that can be simply adjusted by rotating only one mirror. By placing a half-wave plate in one of the interference arms and precisely scanning the relative fiber position, the present invention can expose true apodized fiber Bragg gratings in a single scan by simultaneously rotating the angle of the half-wave plate. By rotationally switching the fast and slow axes of the half-wave plate, the present invention can also expose n-phase-shifted fiber grating by the same system.
Light-emitting device and method for making the same
(2011-02-15)
Chiu
;
Ching-Hua
;
Huang
;
Hung-Wen
;
Kuo
A light-emitting device is capable of emitting a light having a wavelength ranging from 300 to 550 nm, and includes: a substrate; a p-type semiconductor layer disposed on the substrate; an active layer disposed on the p-type semiconductor layer; a n-type semiconductor layer disposed on the active layer and having a waveguide-disposing surface; and a waveguide structure formed on the waveguide-disposing surface of the n-type semiconductor layer and having a plurality of spaced apart nanorods extending from the waveguide-disposing surface.
Method for modulating refractive indices of optical fiber gratings
(2009-09-22)
Hsu
;
Kuei Chu
;
Lai
;
Yin Chieh
The present invention proposes a method for modulating refractive indices of optical fiber gratings, wherein the UV exposure on a least one assigned location of an optical fiber grating is divided into to two UV shots, and the intensities or phases of the two UV shots, which expose the location sequentially, are controlled to make the total exposure intensity of one assigned location maintained at a fixed value, whereby the interference fringes, which are created by a superposition of the two UV shots, have fixed phases and adjustable intensities, and whereby the dc index of the optical fiber grating maintains fixed and the ac index independently adjustable.
Method for sequentially writing fiber Bragg grating by using real-time side-diffraction optical fiber position monitoring
(2008-06-03)
Hsu
;
Kuei-Chu
;
Sheu
;
Lih-Gen
;
Chuang
The present invention provides a fiber Bragg Grating sequential writing method with real-time optical fiber position monitoring, characterized in that the relative phase between a fiber grating and a writing interference beam at each positioning point is determined by an interferometric side-diffraction method, and writing is sequentially performed. Accuracy in fabricating a long and complex fiber grating structure can be increased by decreasing or avoiding accumulative errors caused by long-term scan of monitoring optical fiber position, or by a means for fabricating a wanted reference fiber Bragg grating with similar settings.
Pipeline-based reconfigurable mixed-radix FFT processor
(2010-12-07)
Lai
;
Chi-Chen
;
Hwang
;
Wei
The present invention discloses a fast Fourier transform (FFT) processor based on multiple-path delay commutator architecture. A pipelined architecture is used and is divided into 4 stages with 8 parallel data path. Yet, only three physical computation stages are implemented. The process or uses the block floating point method to maintain the signal-to-noise ratio. Internal storage elements are required in the method to hold and switch intermediate data. With good circuit partition, the storage elements can adjust their capacity for different modes, from 16-point to 4096-point FFTs, by turning on or turning off the storage elements.