Clear Eye Research Articles

A 40-Gbps fiber-FSO convergent transmission system employing OFCL-based WDM and external modulation technique

We have proposed and demonstrated a 40Gbps fiber-free space optics (FSO) convergent system based on external modulation and wavelength division multiplexing (WDM) technique. In this experiment, 4010×4 Gbps signal is successfully transmitted employing WDM scheme over 50 km single mode fiber plus 2.5 km FSO distance. Optical frequency comb lines (OFCL) are generated using a continuous wave laser diode, a radio frequency signal generator, a dual drive Mach Zehnder modulator, and an electrical attenuator. OFC lines, having a side mode suppression ratio (SMSR) value of ∼40 dB and flatness of ∼0.4 dB, are employed as broadband laser source in the presented convergent system. The performance of the fiber-FSO system is investigated theoretically for different weather conditions. Very low power penalty with low bit error rate (BER), clear eye diagrams, and standard Q-factor are achieved in the proposed system. The power penalty is restricted within 2.5 dB and 5.8 dB at a BER of 10−9 for 50 km SMF plus 2.5 km FSO distance in clear weather and 50-km SMF plus 0.4-km FSO distance in heavy fog condition respectively. Thus, the proposed WDM-convergent system is efficient enough for high data rate transmission along with low BER value of ∼10−9 and high Q-factor for different environmental scenarios.

An Inductorless 20-Gbaud Overshoot Suppression Modulator Driver Using Interleave Frequency Variant Feedback in 90-nm CMOS

An inductorless modulator driver with effective overshoot suppression and a large swing for high-speed optical communications is presented. A novel interleave frequency variant feedback (IFVF) technique is proposed, which employs active feedback loops with the RC degeneration. The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$RC$ </tex-math></inline-formula> degeneration allows place the pole in the overall transfer function to shape the waveform for overshoot and ringing suppression. Using a 90-nm complementary metal oxide semiconductor (CMOS) technology, the driver achieves a maximum 3.4 Vpp differential output voltage swing. Clear eye diagrams for non-return to zero (NRZ) and pulse amplitude modulation 4-level (PAM4) signal formats can be obtained up to 32 Gb/s and 20 Gbaud, respectively. The circuit consumes a total power of 560 mW and occupies a core area of only 0.092 mm2.

우리 민사재판의 미래에 관한 소고

Discovery, online litigation, and artificial intelligence are important challenges that can fundamentally change our civil litigation in the future. Discovery needs to be introduced in terms of providing the parties with a means of collecting evidence for the discovery of substantive truth, which must be supplemented in our civil proceedings. However, I suggested that it is reasonable to limit the scope of introduction to appropriate and reasonable measures in consideration of the fact that our legislation does not have a jury system unlike the United States or the expected cost explosion, and that it is necessary to return as a so-called new model to implement preparatory proceedings for pleadings. In addition to electronic lawsuits and video trials already being successfully implemented, ODR, a simple online dispute resolution procedure, should be applied to micro trials to implement online procedures consisting of three pillars of electronic litigation-ODR-video trials. In addition, the possibility of introducing asynchronous hearing in international arbitration or some foreign courts was examined. Artificial intelligence seems to be in the distant future in light of the current technology level, but in light of the rapid development of digital technology, the issue of the emergence of artificial intelligence judges at some point was reviewed in terms of technological and normative substitution. The reason for the existence of civil litigation lies in dispute resolution, so this should be the central value of all procedural laws and systems. Thus, faster, more efficient, and less hostile dispute resolution mechanisms will have to be devised over time. Every attempt has its gain and its loss. It is time for rational and flexible thinking to minimize risk and maximize benefits, so that traditional procedural theories and overwhelming methodological innovations can be exquisitely blended to bring about the best results for dispute resolution. In response to the penetration of new systems and technologies, it is time to draw with a clear and correct eye what civil lawsuits we hope for.

Konsep Dakwah Dalam Novel Bidadari Bermata Bening (Analisis Wacana Teun Van Dijck Novel Bidadari Bermata Bening Karya Habiburrahman El Shirazy)

The novel is one of the print media that is effectively used to convey da'wah messages. The message conveyed from a novel is the intellectual experience and background of the social life of the writer. By reading a novel one can find out the message to be conveyed, the concepts that are instilled and the direction in which the author's thoughts are. This study aims to determine the concept of preaching about faith and the concept of preaching about love in the novel entitled Bidadari Bermata Bening by Habiburrahman El Shirazy. The method used in this research is library research by collecting data and information related to the research object in the form of the da'wah concept contained in the novel Bidadari Bermata Bening by Habiburrahman El Shirazy. The concept in question is in the form of the concept of da'wah about faith and morals. The results of this study concluded that the concept of preaching about faith in the novel Bidadari with clear eyes, whose research focus is in the form of the concept of preaching about faith and the concept of preaching about love in the novel entitled Bidadari with Clear Eyes by Habiburrahman El Shirazy, has Islamic values ​​that are dominant towards the flow of Alhu Sunnah Wal Jama'ah.

A 224 Gb/s EML Sub-Assembly With Electro Optical Bandwidth of 60 GHz for 800GbE Applications

An EML sub-assembly with a terminating resistor optimized for maximum electro-optical bandwidth was successfully demonstrated for 800 GbE applications. To improve the 3-dB electro-optical bandwidth, we employed a newly developed EML with a shorter EA modulator less than 120 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> long, and adjusted the terminating resistance of the transmission line. The fabricated EML sub-assembly exhibited a wide 3-dB bandwidth of 60 GHz without resorting to special assembly techniques such as flip-chip bonding and very short wiring. Furthermore, clear eye openings were obtained for 98 Gbaud PAM4 operation and also 112 Gbaud PAM4 with no sign of excess jitter or overshoot due to pattern effects caused by the modified terminating resistor.

Strong Relationship between Eye Radius and Radius of Maximum Wind of Tropical Cyclones

Abstract Estimation of the radius of maximum wind (RMW) of tropical cyclone (TC) is helpful for the disaster prevention and mitigation. If RMWs are estimated from infrared (IR) imagery taken by geostationary meteorological satellites, their estimation is available densely in time, regardless of the ocean basin. Kossin et al. showed that when TCs have clear eyes, the eye radii estimated from IR images have a high correlation with the RMW estimated from aircraft reconnaissance. The regression of the former onto that latter was shown to have a mean absolute error (MAE) of 4.7 km. We revisit the IR-based RMW estimation by using C-band synthetic aperture radar (SAR) sea surface wind estimates. The criteria for selecting clear-eye cases are simplified. The MAE of the Kossin et al. method is found to be smaller than previously suggested: 3.1 km when the proposed relation is used and 2.7 km when the regression is revised with the SAR-measured RMWs. We further propose an improvement of the IR-based method to estimate the eye radii. The resultant MAE is shown to be 1.7 km, which indicates that the IR-based RMW estimation is more accurate than has been suggested. A strong correlation between eyewall slope and eye size is confirmed. We also investigated cloud features in the eye that may be closely related to RMW and wind structure around RMW. Potential applications of highly accurate RMW estimation are discussed. Significance Statement The radius of maximum wind (RMW) of tropical cyclone (TC) is an important factor for TC intensity estimation and disaster prevention. A previous study suggested that the RMWs of TCs with clear eyes can be estimated from geostationary satellite images at a mean absolute error (MAE) of 4.7 km. Here we improved the method, reducing the MAE by more than one-half. Since the method does not require aircraft or satellite in low Earth orbit, it helps TC monitoring at high frequency. The method can also improve initialization of models used to predict TC hazards and further our physical understanding and the climatology of the wind structures near the centers of TCs.

Over-67-GHz-Bandwidth Membrane InGaAlAs Electro-Absorption Modulator Integrated With DFB Laser on Si Platform

We fabricate a membrane InGaAlAs electro-absorption modulator (EAM) integrated with a distributed feedback (DFB) laser combining direct wafer bonding and epitaxial regrowth of InP-based layers on a silicon-on-insulator wafer. Heterogeneous integration of an InP-based multiple-quantum-well (MQW) layer into the Si photonics simplifies the integration of the O-band EAMs and laser diodes (LDs). EAMs and LDs can be fabricated using the same MQW layer because of the wide operating range and the direct bandgap of the MQWs. A compact and high-speed lumped-electrode EAM can be made because the membrane lateral p-i-n diode structure has low capacitance and a large optical confinement factor. The effective-refractive-index matching between the membrane InP and Si layers enables the DFB laser to be fabricated with a low-loss supermode waveguide whose MQW core was optically coupled to the Si core. The fabricated 100-μm-long membrane EAM has a high modulation efficiency of about 3 dB/V at 1260 nm and E-O bandwidth of over 67 GHz even without a 50-ohm termination. The EAM-integrated DFB laser has a fiber coupled output power of about −2 dBm and clear eye openings with an extinction ratio of 3.8 and 3.2 dB for 100- and 112-Gbit/s non-return-to-zero signals, respectively.

Impact of Carrier Transport and Capture on VCSEL Dynamics

Using a vertical-cavity surface-emitting laser (VCSEL) equivalent circuit model based on two carrier rate equations to include effects of carrier dynamics, we study the impact of carrier transport and capture on the small- and large-signal modulation response of high-speed VCSELs. The model also accounts for parasitics, current-induced self-heating, and gain compression. A variation of the effective capture time from 1 to 15 ps is found to have a large impact on the small-signal modulation response, with the 3 dB bandwidth decreasing from 40 to 15 GHz and the response transitioning from under-damped to over-damped. This is primarily due to the increasing low frequency parasitic-like roll-off with increasing effective capture time. A significant effect on the optical waveforms produced by the VCSEL under 56 Gbit/s on-off keying (OOK) non-return-to-zero (NRZ) and pulse-amplitude modulation 4 (PAM4) modulation is observed, with a short effective capture time leading to horizontal eye closure caused by timing jitter (TJ) and intersymbol interference (ISI) and a long effective capture time leading to vertical eye closure caused by long rise- and fall-times. However, for high modulation speed, a short effective capture time is needed and the photon lifetime should be set for clear eye opening. We also show the impact of the effective capture time on the output power vs current characteristics and map the dependence of internal temperature, carrier densities, carrier escape and leakage rates, and spontaneous recombination rates on current for different effective capture times.

16-channel photonic–electric co-designed silicon transmitter with ultra-low power consumption

A hybrid integrated 16-channel silicon transmitter based on co-designed photonic integrated circuits (PICs) and electrical chiplets is demonstrated. The driver in the 65 nm CMOS process employs the combination of a distributed architecture, two-tap feedforward equalization (FFE), and a push–pull output stage, exhibiting an estimated differential output swing of 4.0Vpp. The rms jitter of 2.0 ps is achieved at 50 Gb/s under nonreturn-to-zero on–off keying (NRZ-OOK) modulation. The PICs are fabricated on a standard silicon-on-insulator platform and consist of 16 parallel silicon dual-drive Mach–Zehnder modulators on a single chip. The chip-on-board co-packaged Si transmitter is constituted by the multichannel chiplets without any off-chip bias control, which significantly simplifies the system complexity. Experimentally, the open and clear optical eye diagrams of selected channels up to 50 Gb/s OOK with extinction ratios exceeding 3 dB are obtained without any digital signal processing. The power consumption of the Si transmitter with a high integration density featuring a throughput up to 800 Gb/s is only 5.35 pJ/bit, indicating a great potential for massively parallel terabit-scale optical interconnects for future hyperscale data centers and high-performance computing systems.

75 GHz germanium waveguide photodetector with 64 Gbps data rates utilizing an inductive-gain-peaking technique

High-performance germanium (Ge) waveguide photodetectors are designed and fabricated utilizing the inductive-gain-peaking technique. With the appropriate integrated inductors, the 3-dB bandwidth of photodetectors is significantly improved owing to the inductive-gain-peaking effect without any compromises to the dark current and optical responsivity. Measured 3-dB bandwidth up to 75 GHz is realized and clear open eye diagrams at 64 Gbps are observed. In this work, the relationship between the frequency response and large signal transmission characteristics on the integrated inductors of Ge waveguide photodetectors is investigated, which indicates the high-speed performance of photodetectors using the inductive-gain-peaking technique.

Laser-Based Optical Wireless Communications for Internet of Things (IoT) Application

Internet of Things (IoT) is enabled by the integration of communication and sensor systems that are used to collect important information from objects around the world. In this article, we proposed the integration of laser-based optical wireless communication (OWC) with a fiber sensor system for IoT applications. OWC can be utilized in a harsh environment to send and receive communication and sensor signals in a wireless means. Moreover, fiber sensors are important to achieve real-time, accurate, and smart monitoring in IoT applications. As compared to mechanical and electrical sensors, optical fiber sensors have numerous benefits, including the tolerance to electromagnetic interference (EMI), small size, lightweight, high bandwidth, low cost, provide distributed sensing, high sensitivity, and electronic devices are not required at the sensor point. Moreover, we proposed a deep variational autoencoder (DVAE) model to estimate the strain changes and peak wavelength of multiple fiber Bragg grating (FBG) sensors using only the spectrum of FBGs obtained from the real experiment. The result showed that our proposed DVAE model can estimate the strain changes and peak wavelength of FBGs with low root mean squared error (RMSE) and high estimation accuracy. Furthermore, the performance of the proposed integration of OWC with the fiber sensor system achieves a clear eye diagram and excellent bit error rate (BER) curve.

TINDAK TUTUR EKSPRESIF DALAM NOVEL BIDADARI BERMATA BENING KARYA HABIBURRAHMAN EL SHIRAZY

The novel Bidadari with Clear Eyes by Habiburrahman El Shirazy. This novel presents an interesting story about the lives of young people in a pesantren as a medium for researching expressive speech acts. The purpose of this study was to describe the types of expressive speech acts and expressive speech acts in the novel Bidadari Bermata Bening. This research uses descriptive qualitative research method. Data collection in this study is in the form of quotes between dialogues of the characters. In the types of speech acts in the novel Bidadari Bermata Bening by Habiburrahman El Shirazy, 18 utterances of expressive gratitude were found with meaning as a form of help and expressive speech acts of praise as many as 13 utterances with meaning as a form of praise.Keywoards: Speech Acts, Expressive Speech Acts, Novels.

The numerical investigations of SiGe/Si heterojunction electro-optic modulator in mid-infrared

We present the detailed numerical analysis and characterization of SiGe/Si heterojunction electro-optic modulator at 2 μm, 4.3 μm, and 5 μm wavelengths. We investigate the band, the refractive index, and the carrier injection efficiency of SiGe/Si heterojunction PIN electrical structure. Numerical investigations are carried out on the key geometrical parameters, doping concentration, Ge content. The results show that the modulated voltage of SiGe/Si PIN heterojunction modulator is lower 50% than that of Si modulator under the same modulation effect. In order to eliminate the absorption losses of SiO2 in mid-infrared, the punch Mach–Zehnder optical structure is established and researched. The research present that the modulator has the short 500 µm phase shifters and the low VπLπ of 0.042 Vcm under forward bias voltage, and the extinction ratio is greater than 12.81 dB. The high-speed transmission characteristics are shown to have clean eye diagrams up to 40 Gbps in mid-infrared.

Si Photonic-Integrated Chip Assembly With Waveguide Ge Avalanche Photodiode for 10 Gbps L-Band Optical Access Networks

The receiving characteristics of the silicon photonic-integrated chip assembly consisting of transimpedance amplifiers and butt-joint waveguide germanium avalanche photodiodes with lateral separated absorption and multiplication (SAM) structures were demonstrated based on conventional complementary metal-oxide-semiconductor processes. We experimentally verified a clear open eye diagram at 10 Gbps with a reverse bias of 17 V. Receiving sensitivities of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$-$</tex-math></inline-formula> 22.8 dBm and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$-$</tex-math></inline-formula> 22.0 dBm were obtained for the best and worst polarizations, respectively, with optical signals that had wavelengths longer than those of the absorption edges of Ge at a bit rate of 10 Gbps and a wavelength of 1600 nm. The proposed waveguide butt-joint germanium avalanche photodiodes with lateral SAM structures can be used to receive long wavelengths of downstream signals with low polarization dependence in next-generation optical access network systems.

A Monolithic Optoelectronic Integrated Circuit of InP p-i-n/Double HBTs Through Transfer-Printing Fabrication

In this letter, we present a photoreceiver front-end circuit that consists of an InP p-i-n photodetector (PIN PD) on an InP transimpedance amplifier (TIA) with double HBTs (DHBTs), in which the key integrated fabrication route of a transfer-printing (TP) process is introduced. Prior to integration, PDs and TIAs are individually fabricated on their respective wafers. Then, a discrete PD with only active layers is transferred onto the destination on a TIA wafer, thereafter, an on-chip coplanar waveguide connection is integrated. The PIN PD and DHBT TIA exhibit excellent performance, characterized by a responsivity of 0.51 A/W at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.55~\mu \text{m}$ </tex-math></inline-formula> with a bandwidth of 20 GHz and a transimpedance gain of 36 dB <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> with a bandwidth of 27 GHz, respectively. Finally, the monolithically integrated circuit demonstrates a better frequency response by maximally reducing the parasitic effect, with an open clear eye diagram under a 20 Gb/s nonreturn-to-zero pattern, which evidently manifests its ability for ultrahigh-rate data operation. The present work, by employing a TP process, overcomes the issues in integrating discrete optoelectronic devices and proposes a unique approach for monolithic optoelectronic integrated circuit fabrication.

Operating performance of silicon photonic optical switches integrated with WDM filters for low-latency edge-computing platforms

We investigated the performance of a silicon photonic device integrating pn-junction-type Mach-Zehnder interferometer optical switches with wavelength-division-demultiplexing and multiplexing (WDM-DEMUX and MUX) filters that perform switching operations to transmit packet data between edge computing. After separating the 1535 and 1565 nm signals with the Mach-Zehnder delay interferometer-type WDM-DEMUX/MUX filters, cascaded dynamic switching operation with a few nanoseconds turn-on/off for On-Off keying (OOK) signals at 10 Gbps were achieved. The power penalty difference between the input and output was within 0.5 dB for 1565-nm signals. We also verified the switching operation at a bit rate of 25 Gbps and observed clear eye openings.

Dear Casey Kasem. I am no longer a magpie

Dear Casey Kasem. I am no longer a magpie Alexa Doran (bio) I am giving up. all reason for air to ankle me. I am no longer looking. for the girl I used. to be: sixteen and Swisher stoned at the creek. You won't find her. in the wing tall hush buying. blue-razz icees or skipping. French to spy on the private. school's soccer team. Those are stains only. one in flight could breed. But DJ Kasem I am at rest. Now I wait patiently. Radio just keeps getting stronger you tell your interviewer. the millionth who believes you. will phantom. will succumb. will admit to wanting. to run. Unlike me these women. still search for the shiny. still come for the coin. still waddle bedraggled in jewelry. None of us seek victory. So why do they glove you in vodka. clear eyes and pity. while I pond the corner. algae who never tendrils. only throats and receives [End Page 319] Alexa Doran Alexa Doran recently completed her PhD in Poetry at Florida State University. Her full-length collection DM Me, Mother Darling won the 2020 May Sarton New Hampshire Poetry Prize and was published in April 2021 (Bauhan). She is also the author of the chapbook Nightsink, Faucet Me a Lullaby (Bottlecap Press 2019). You can look for work from Doran in recent or upcoming issues of Passages North, Literary Mama, Tinderbox Poetry Journal, Salt Hill Journal, and Anti-Heroin Chic, among others. For a full list of her publications, awards, and interviews please visit her website at alexadoran.com. Copyright © 2022-2023 Pleiades and Pleiades Press

Hybrid of Free Space Optics Communication and Sensor System Using IWDM Technique

In this work, we designed a novel hybrid of free-space optics (FSO) communication and intensity and wavelength division multiplexing (IWDM)-fiber Bragg grating (FBG) sensor system over a single shared FSO transmission channel for both optical and sensor signal transmission. In the proposed system, we use one broadband light source and one FSO link for both optical and FBG sensor signal transmission, which significantly reduces the cost of system installation and complexity. Besides, the FSO transmission channel is used to solve the problem of geographical constraints when the environment is difficult to install the fiber. In addition, IWDM is one of the best multiplexing technique to increase the sensor number by more than two times the conventional wavelength division multiplexing (WDM) method. Besides, to solve the overlap spectra problem of IWDM based FBG sensor system, we proposed the stacked gated recurrent unit (SGRU) algorithm with the neural network (NN) profile method. The results prove that the proposed SGRU with the NN profile method improves the accuracy of wavelength detection techniques with the Gaussian profile method. Moreover, the FSO transmission channel achieves a clear eye diagram even the system is a hybrid of optical communication and FBG sensors system.

67 GHz light-trapping-structure germanium photodetector supporting 240 Gb/s PAM-4 transmission

A light-trapping-structure vertical Ge photodetector (PD) is demonstrated. In the scheme, a 3 μm radius Ge mesa is fabricated to constrain the optical signal in the circular absorption area. Benefiting from the light-trapping structure, the trade-off between bandwidth and responsivity can be relaxed, and high opto-electrical bandwidth and high responsivity are achieved simultaneously. The measured 3 dB bandwidth of the proposed PD is around 67 GHz, and the responsivity is around 1.05 A/W at wavelengths between 1520 and 1560 nm. At 1580 nm, the responsivity is still over 0.78 A/W. A low dark current of 6.4 nA is also achieved at − 2 V bias voltage. Based on this PD, a clear eye diagram of 100 GBaud four-level pulse amplitude modulation (PAM-4) is obtained. With the aid of digital signal processing, 240 Gb/s PAM-4 signal back-to-back transmission is achieved with a bit error ratio of 1.6 × 10 − 2 . After 1 km and 2 km fiber transmission, the highest bit rates are 230 and 220 Gb/s, respectively.

1600 Gbps PAM-4 FSO link enabled using OFCL-based WDM and OAM-multiplexing techniques

The twisted light beams carry orbital angular momentum (OAM), which acts as additional degrees of freedom. In this work, we have proposed a free space optics (FSO) communication system employing wavelength division multiplexing (WDM), OAM multiplexing, and four-level pulse amplitude modulation (PAM-4) techniques. A 1600 Gbps data has been successfully transmitted over free space in different environmental scenarios such as clear weather, weak turbulence, moderate turbulence, and strong turbulence. The effects of atmospheric turbulence on the PAM-4 signals carrying OAM modes are examined theoretically and simulated for the first time. Optical frequency comb lines are generated by employing a single laser source and used as a broadband laser source. A sufficient low power penalty of 1.489 dB at a BER value ∼ 10-9 along with clear eye diagrams has been achieved for the proposed system. Thus, the proposed 1600 Gbps PAM-4, OAM, and WDM-based system can be a promising solution for the next generation of long-reach and high-data-rate free-space communication.