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A novel process using self-aligned microbonding technique to make Ge/Si heterojunction PIN waveguide photodetectors for operation over 10GHz
No full text[[fileno]]2030192030003[[department]]電機工程學
Doppler measurement on rough surfaces with dual-wavelength lidar based on optically injected semiconductor laser
No full text[[fileno]]2030181030035[[department]]電機工程學
Demonstration of arbitrary channel selection in microwave frequency comb
No full text[[abstract]]We demonstrate arbitrary channel selection in microwave frequency comb by an optically-injected double phase-locked semiconductor laser. Suppression ratios of 41.8 and 25.9 dB between the main and secondary channels to the others are achieved.[[fileno]]2030181030039[[department]]電機工程學
Saliency-based image retargeting in compressed domain
No full text[[abstract]]In this paper, we propose a novel image retargeting algorithm to resize images based on the extracted saliency information from the compressed domain. Firstly, we utilize DCT coefficients in JPEG bitstream to perform saliency detection with the consideration of the human visual sensitivity. The obtained saliency information is used to determine the relative visual importance of each 8 x 8 block for the image. Furthermore, we propose a new adaptive block-level seam removal operation for connected blocks to resize the image. Thanks to the directly derived saliency information from the compressed domain, the proposed image retargeting algorithm effectively preserves the objects of attention, efficiently removes the less crucial regions, and therefore significantly outperforms the relevant state-of-the-art algorithms, as demonstrated with the careful analysis and in the extensive experiments.[[fileno]]2030144030094[[department]]電機工程學
Remotely Up-converted 20 Gbit/s Error-Free Wireless On-off-keying Data Transmission at W-band using an Ultra-Wideband Photonic Transmitter-Mixer
Get PDF[[abstract]]We demonstrate a remotely up-converted and distributed 20-Gbit/s wireless on-off-keying (OOK) data transmission link at the W-band that uses a near-ballistic uni-traveling-carrier photodiode (NBUTC-PD)-based photonic transmitter-mixer. This device consists of an active NBUTC-PD integrated with a planar passive circuit for feeding the intermediate-frequency (IF) modulation input and extracting the up-converted optical-to-electrical (O-E) output signals. An equivalent-circuit model is developed, which allows for the O-E and IF responses to be independently optimized. Accordingly, we can achieve both an ultra-wide O-E bandwidth (67-118 GHz) and IF modulation bandwidth (>;15 GHz) with a very-low coupling loss (<; 2 dB) from the NBUTC-PD to the WR-10 waveguide. We adopted a remotely distributed 1-ps optical pulse train source with a repetition rate at 93 GHz to serve as a high-performance photonic carrier, which is generated by a spectral line-by-line shaper utilizing the repetition-rate multiplication (RRM) technique. In contrast to lossy amplitude filtering, our RRM is based on applying periodic loss-less spectral phase filtering onto the 31-GHz comb lines. In comparison with the conventional 93-GHz sinusoidal carrier, the photogenerated millimeter-wave (MMW) power of this kind of carrier is 4 dB higher than that of PD under the same output photocurrent. In contrast to the traditional mode-locked laser, the fiber dispersion can be totally precompensated without additional dispersion compensation components. By use of such device and optical MMW source, we successfully demonstrate remotely distributed and up-converted 20-Gbit/s error-free OOK wireless data transmission link over a 25-km standard single-mode fiber.[[fileno]]2010144010198[[department]]物理
An ultrabroad terahertz bandpass filter based on multiple-resonance excitation of a composite metamaterial
Get PDF[[abstract]]We experimentally present an ultrabroad terahertz (THz) bandpass filter based on a composite metamaterial (CMM) by exciting its multiple resonances. This metamaterial-based filter, consisting of a metal-dielectric-metal sandwiched structure, possesses a notable spectral-filtering capability with a 0.5-THz-broad bandwidth and excellent band-edge transitions of 140% THz and 182% THz in the THz-gap region. Furthermore, we manifest the mechanism for each of the resonances and the coupling within the composite metamaterial. This realization enables the capacity for engineering the electromagneticproperties to develop other complex optical functionalities. An example of a high-profile dualband THz bandpass filter is also proposed theoretically in this work.[[fileno]]2010144010207[[department]]物理
Adaptive Upstream Rate Adjustment by RSOA-ONU Depending on Different Injection Power of Seeding Light in Standard-Reach and Long-Reach PON Systems
No full text[[abstract]]The wavelength division multiplexing-time division multiplexing (WDM-TDM) passive optical network (PON) using reflective semiconductor optical amplifier (RSOA)-based colorless optical networking units (ONUs) is considered as a promising candidate for the realization of fiber-to-the-home (FTTH). And this architecture is actively considered by Industrial Technology Research Institute (ITRI) for the realization of FTTH in Taiwan. However, different fiber distances and optical components would introduce different power budgets to different ONUs in the PON. Besides, due to the aging of optical transmitter (Tx), the power decay of the distributed optical carrier from the central office (CO) could also reduce the injection power into each ONU. The situation will be more severe in the long-reach (LR) PON, which is considered as an option for the future access. In this work, we investigate a WDM-TDM PON using RSOA-based ONU for upstream data rate adjustment depending on different continuous wave (CW) injection powers. Both standard-reach (25 km) and LR (100 km) transmissions are evaluated. Moreover, a detail analysis of the upstream signal bit-error rate (BER) performances at different injection powers, upstream data rates, PON split-ratios under stand-reach and long-reach is presented.[[fileno]]2010144010218[[department]]物理
現階段「台灣研究」的文學問題
No full text[[abstract]]題目是設定「台灣研究」為主旨，在現階段，就文學領域內諸問題加以探討。[[fileno]]204_JA05_1993_n1_p2
