Journal articles: 'Fibre Channel (Standard)'

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Volavy, Jaroslav, Árpád Farkas, Frantisek Lizal, Jakub Elcner, and Miroslav Jicha. "Lagrangian tracking of fibres in a channel flow." EPJ Web of Conferences 213 (2019): 02098. http://dx.doi.org/10.1051/epjconf/201921302098.

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Tracking of fibres in a fluid flow is much more complicated than tracking of spherical particles. In fibre motion, the orientation of fibre against the flow direction plays a very important role. In addition to the standard equation of motion, additional equations for orientation and angular velocity must be solved during the tracking of fibres. A mathematical model describing fibre motion is introduced in this work. Capabilities of this model are demonstrated through simulations of fibre transportation by air in a channel flow. The importance of the terms in the equation of angular velocity are discussed.

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Morita, I., K. Tanaka, N. Edagawa, and M. Suzuki. "40 Gbit/s single-channel transmission over standard singlemode fibre using distributed Raman amplification." Electronics Letters 36, no. 25 (2000): 2084. http://dx.doi.org/10.1049/el:20001479.

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Alleston, S. B., P. Harper, I. S. Penketh, I. Bennion, and N. J. Doran. "40 Gbit/s single channel dispersion managed pulse propagation in standard fibre over 509 km." Electronics Letters 35, no. 1 (1999): 57. http://dx.doi.org/10.1049/el:19990006.

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Mezentsev, V. K., S. K. Turitsyn, and N. J. Doran. "System optimisation of 80 Gbit/s single channel transmission over 1000 km of standard fibre." Electronics Letters 36, no. 23 (2000): 1949. http://dx.doi.org/10.1049/el:20001364.

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Swamy, L. Radha, Chinnasamy Senthamaraikannan, and R. Ramesh. "Investigation of the Elastic Modulus Effect on Free Vibration Characteristics of Fiber Reinforced Polymer Composite Beams Made of Various Fundamental Shapes." Advanced Materials Research 1088 (February 2015): 401–6. http://dx.doi.org/10.4028/www.scientific.net/amr.1088.401.

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Woven fiber reinforced polymer composites plays major role in structural applications. Structures subjected to dynamic situations, this leads to increased attention in finding characteristic behaviour/performance of FRP composites beams under vibrating conditions. The objective of this work is to understand and investigate the influence of cross sectional shapes of beams on successive vibration resonance frequencies and its damping performance under cantilever end conditions. The beams were fabricated by hand lay-up method in two different modulus material and cross sections like I and channel; maintaining uniform cross sectional area and moment of inertia apart from length of the beams using woven carbon fibre. The investigation was performed by impulse frequency response method using standard test procedure on low modulus Glass/epoxy composite beams and compared with high modulus Carbon/epoxy beams. Frequency response curve of I and channel shaped beams were compared for their damping performance. The modal frequencies of all fabricated beams were obtained using MEScopeVES® software and modal resonant frequencies, loss factor were compared against shapes.

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Mary Joseph, Nisha, and C. Puttamadappa. "Estimation of channel distortion in orthogonal frequency division multiplexing system using pilot technique." Indonesian Journal of Electrical Engineering and Computer Science 28, no. 1 (October 1, 2022): 106. http://dx.doi.org/10.11591/ijeecs.v28.i1.pp106-114.

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Orthogonal frequency-division multiplexing (OFDM) is resistant to frequency selective fading due to the longer symbol duration. However, mobile applications channel timing fluctuations in one OFDM signal cause intercarrier-interference (ICI), which reduces performance. This research presented the support vector regression (SVR) model-based channel estimation technique for coherent optical communication systems. Due to the coherent optical orthogonal frequency-division-multiplexed (COOFDM) system, a channel model is developed that includes linear fibre dispersion effects, noise from optical amplifiers, and inter-carrier interference generated by laser phase noise. As a result, for such a system, an accurate channel estimate is essential. Based on this concept, derivation of channel estimation and phase estimation for the system of CO-OFDM. The proposed method is tested and evaluated using MATLAB software. Computer simulation results for several standard methods such as extreme learning machines (ELM) and artificial neural networks (ANN) validate the feasibility of the suggested methodology. The CO-OFDM system’s transmission experiments and computer simulations prove that the support vector machine-based model following pilot-assisted phase estimation gives the optimal performance. Therefore, results depicted that the channel estimation utilizing the SVR model gives good performance than the other methods, thus the proposed model gives an accurate CE process, respectively.

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Alleston, S. B., P. Harper, I. S. Penketh, I. Bennion, N. J. Doran, and A. D. Ellis. "1000 km transmission of 40 Gbit/s single channel RZ data over dispersion managed standard (non-dispersion shifted) fibre." Electronics Letters 35, no. 10 (1999): 823. http://dx.doi.org/10.1049/el:19990566.

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Bahaweres, Rizal, Tjetjep Rony Budiman, and Andi Adriansyah. "ANALISIS KINERJA ISCSI TARGET PADA WIRELESS LAN MEMAKAI STANDAR LIO." SINERGI 19, no. 1 (February 1, 2015): 25. http://dx.doi.org/10.22441/sinergi.2015.1.005.

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Semakin banyaknya kebutuhan data center maupun laboratorium komputer di Indonesia dipengaruhi oleh semakin banyaknya pengguna yang memanfaatkan komputer baik untuk bisnis maupun pendidikan. Salah satu kebutuhan utama yang tidak bisa dilepaskan dari pemakaian komputer adalah tempat penyimpanan baik berupa USB Flash Disk, HD Eksternal, HD Internal sampai HD untuk kebutuhan skala besar untuk komputer server yang berada di data center, laboratorium atau jaringan komputer. Ruang penyimpanan data atau data storage semakin berkembang dengan munculnya teknologi komputer jaringan yang memunculkan alternatif data storage berupa DAS, NAS, FC, FcoE dan iSCSI. iSCSI menggunakan standard TCP/IP protocol over Ethernet untuk menyediakan penyimpanan berbasis block. Saat ini ada 2 jenis multiprotocol SCSI Target utama di industri yaitu LIO dan COMSTAR yang menggantikan teknologi sebelumnya yaitu iET, SCST dan STGT. LIO (linux-iscsi.org) merupakan standard open source iSCSI Target untuk berbagi ruang penyimpanan di Linux. LIO mendukung storage fabrics, yaitu Fibre Channel (QLogic), FCoE, iEEE 1394, iSCSI, iSER (Mellanox InfiniBand), SRP (Mellanox InfiniBand), USB, vHost, dan lain-lain.

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Ludwig, R., W. Pieper, H. G. Weber, D. Breuer, K. Petermann, F. Küppers, and A. Mattheus. "Unrepeatered 40 Gbit/s RZ single channel transmission over 150 km of standard singlemode fibre at 1.55 [micro sign]m." Electronics Letters 33, no. 1 (1997): 76. http://dx.doi.org/10.1049/el:19970032.

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Bracknell, D. R. "The MIL-STD-1553B data bus: What does the future hold?" Aeronautical Journal 111, no. 1118 (April 2007): 231–46. http://dx.doi.org/10.1017/s0001924000004486.

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Numerous military platforms (land, sea and air) feature serial data bus technology based on the US MIL-STD-1553B data bus standard for integration of their digital systems. Many of these platforms have 15-20 years of operational life remaining, but the installed 1553B data buses (data networks) having only a 1Mbit/sec transfer rate are unable to meet many of the future data networking requirements. Research into new, higher performance data networks has concentrated on modern alternatives with throughput increases of two to three orders of magnitude (100Mbit/sec to 1Gbit/sec). These are generally based on modern commercial-off-the-shelf (COTS) standards, good examples being Ethernet and Fibre Channel. Some are already being employed in military platforms having been ruggedised for the harsh physical and electro-magnetic environment. However these COTS systems while being a natural choice for new platforms may not be cost effective for upgrading older platforms. This paper plots the history of MIL-STD-1553, possibly the most successful military platform standard of all time, and discusses some of the options for increasing its performance and economically extending its life into the future.

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Pavlovs, D., V. Bobrovs, M. Parfjonovs, A. Alsevska, and G. Ivanovs. "Investigation of Power Efficiency Changes in DWDM Systems Replacing Erbium-Doped Amplifiers By Semiconductor Optical Amplifiers." Latvian Journal of Physics and Technical Sciences 59, no. 1 (February 1, 2022): 44–52. http://dx.doi.org/10.2478/lpts-2022-0005.

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Abstract To evaluate potential utilization of semiconductor optical amplifiers (SOAs) as a wideband amplification alternative to erbium doped fibre amplifiers (EDFAs) in dense wavelength division multiplexed (DWDM) coherent systems, the authors discuss changes in power consumption levels required for a single bit transmission. The research evaluates the power efficiency parameter for WDM transmission systems using both amplification schemes – EDFAs that utilise standard C-band and SOAs assuming 75 nm amplification spectral band. The power efficiency levels have been estimated for five transmission spans with maximal distance of 640 km. The standard 50 GHz channel spacing has been chosen for both system configurations to allocate 100 Gbps dual-polarization quadrature phase shift keying (DP-QPSK) optical signals. The simulation schemes are described along with the critical parameters, derived from the recent relevant studies that should be taken into account considering usage of SOAs as in-line amplifiers.

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Appathurai, S., V. Mikhailov, R. I. Killey, and P. Bayvel. "Effective suppression of intra-channel nonlinear distortion in 40 Gbit∕s transmission over standard singlemode fibre using alternate-phase RZ and alternate polarisation." Electronics Letters 40, no. 14 (2004): 897. http://dx.doi.org/10.1049/el:20045019.

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Feiste, U., R. Ludwig, S. Diez, C. Schmidt, H. J. Ehrke, H. G. Weber, and F. Küppers. "Unrepeatered 80 Gbit/s RZ single channel transmission over 160 km of standard fibre at 1.55 [micro sign]m with large wavelength tolerance." Electronics Letters 36, no. 6 (2000): 561. http://dx.doi.org/10.1049/el:20000467.

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Ludwig, R., U. Feiste, S. Diez, C. Schubert, C. Schmidt, H. J. Ehrke, and H. G. Weber. "Unrepeatered 160 Gbit/s RZ single-channel transmission over 160 km of standard fibre at 1.55 [micro sign]m with hybrid MZI optical demultiplexer." Electronics Letters 36, no. 16 (2000): 1405. http://dx.doi.org/10.1049/el:20001006.

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OLALEKAN, APENA WALIU, OLASUNKANMI OMOWUMI GRACE, and SALAKO ANUOLUWAPO. "PERFORMANCE EVALUATION OF ETHERNET TRANSMISSION USING M-ARY PULSE AMPLITUDE MODULATION TECHNIQUES." Journal of Engineering Studies and Research 26, no. 4 (January 8, 2021): 74–85. http://dx.doi.org/10.29081/jesr.v26i4.239.

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Low installation costs and high data rates reaching up to 10 Gbps, characterized Ethernet as the local area network (LAN) technology of choice to satisfy the increasing need for high-speed data transmission in packet-based networks. As demand for high speeds in data has increased, copper Ethernet has been integrated to handle these higher speeds. The IEEE 802.3ae* 2002 (10 Gigabit Ethernet) standard is based on data transmission over optical fibre only and in full-duplex mode. This study considered performance evaluation of Pulse Amplitude Modulation (PAM) and multilevel (PAM-16) technology in comparison with other PAM versions was carried out to investigate copper Ethernet with respect to higher speed characteristic and error performance. The evaluation was carried out in MATLAB R2017b simulation environment; this provides calculated bit error rates (BER) of the considered modulation schemes under different channel conditions. The results show that PAM-16 has a BER of .which is significantly lower than that of PAM-2 and PAM-4. Additionally, Hamming code were used to detect and correct errors that are inherent in the design and the efficiency of each level of PAM used was analyzed.

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Oesinghaus, Helge, Daniel Wanken, Kilian Lupp, Martina Gastl, Martin Elsner, and Karl Glas. "Incipient Biofouling Detection via Fiber Optical Sensing and Image Analysis in Reverse Osmosis Processes." Membranes 13, no. 6 (May 25, 2023): 553. http://dx.doi.org/10.3390/membranes13060553.

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Reverse osmosis (RO) is a widely used membrane technology for producing process water or tap water that is receiving increased attention due to water scarcity caused by climate change. A significant challenge in any membrane filtration is the presence of deposits on the membrane surfaces, which negatively affect filtration performance. Biofouling, the formation of biological deposits, poses a significant challenge in RO processes. Early detection and removal of biofouling are essential for effective sanitation and prevention of biological growth in RO-spiral wound modules. This study introduces two methods for the early detection of biofouling, capable of identifying initial stages of biological growth and biofouling in the spacer-filled feed channel. One method utilizes polymer optical fibre sensors that can be easily integrated into standard spiral wound modules. Additionally, image analysis was used to monitor and analyze biofouling in laboratory experiments, providing a complementary approach. To validate the effectiveness of the developed sensing approaches, accelerated biofouling experiments were conducted using a membrane flat module, and the results were compared with common online and offline detection methods. The reported approaches enable the detection of biofouling before known online parameters become indicative, effectively providing an online detection with sensitivities otherwise only achieved through offline characterization methods.

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Sachs, M. W., and A. Varma. "Fibre Channel and related standards." IEEE Communications Magazine 34, no. 8 (1996): 40–50. http://dx.doi.org/10.1109/35.533918.

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Tsai, Wen-Shing, Hong-Yu Dai, and Chung-Yi Li. "Based on FP LDs with split band technique in two-channel fiber optical CATV transport system." MATEC Web of Conferences 185 (2018): 00015. http://dx.doi.org/10.1051/matecconf/201818500015.

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This study proposes a two-channel fiber optic cable television (CATV) transport system based on Fabry–Perot laser diodes (FP-LDs) with a split band technique. To reduce the interference between channels, we apply the split band technique to two channels with different frequencies by using two converters at each moment. In this two-channel transmission scheme, composite second-order (CSO) and composite triple-beat (CTB) distortions induced by the systems are possibly confined in unused channels and result in good transmission performances. Through a 40 km standard single-mode fiber transmission, excellent performances of carrier-to-noise ratio (≥50 dB), CSO (≥70 dB), and CTB (≥72 dB) are obtained using the proposed fiber optic CATV transport systems. The proposed systems employing FP-LDs with a split band technique are also simpler and more cost effective than conventional externally modulated systems.

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Huang, Li Qun, and Guang Yang. "Fiber Grating Based 64-Channel Interleavers with 25GHz Channel Spacing and Flat-Top Passbands." Applied Mechanics and Materials 347-350 (August 2013): 1251–55. http://dx.doi.org/10.4028/www.scientific.net/amm.347-350.1251.

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An interleaver can separate odd and even channels into two signal streams. In this paper, a novel chirp fiber grating with 14cm length is designed by using the layer-peeling algorithm, which can implements the function of a broadband interleaver with 25GHz channel spacing. The interleaver has 64 channels and flat-top passbands, and its channel isolation is above 28.5dB. All passband central wavelengths are suited for ITU standards, moreover, this grating-based interleaver can be manufactured by existing technologies.

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Cho, Junghwan, Paul J. Gemperline, and Dwight Walker. "Wavelength Calibration Method for a CCD Detector and Multichannel Fiber-Optic Probes." Applied Spectroscopy 49, no. 12 (December 1995): 1841–45. http://dx.doi.org/10.1366/0003702953966055.

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A wavelength calibration method for a charge-coupled device (CCD) array detector and seven-channel fiber-optic spectrograph is described. The method was developed for the extraction of wavelength-calibrated spectra for in situ dissolution testing of tablets. The method includes automatic recognition of the positions of the seven fiber channels and recognition of mercury line positions in pixel numbers. A wavelength calibration model with two trigonometric terms was used for least-squares fitting of horizontal pixel numbers to the known wavelengths of five lines from a low-pressure mercury discharge lamp. Four other models were used for comparison. The standard error of estimate (SEE) was minimum for the model with two trigonometric terms. Each fiber channel was calibrated separately. After least-squares fitting, linear interpolation was used to obtain the wavelength-calibrated spectra in the range of 190–450 nm at 1-nm intervals. With this method, spectra from seven fiber-optic probes can be acquired simultaneously and rapidly for in situ dissolution testing. The wavelength calibration procedure is good enough to permit solution spectra acquired on one channel to be used for multivariate calibration of the other channels under appropriate circumstances.

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Mengesha, Befekadu, Pablo Torres-Ferrera, and Roberto Gaudino. "Analysis of 5G New Radio Uplink Signals on an Analogue-RoF System Based on DSP-Assisted Channel Aggregation." Applied Sciences 9, no. 1 (December 24, 2018): 47. http://dx.doi.org/10.3390/app9010047.

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The 3rd Generation Partnership Project (3GPP) is in the process of developing 5th generation (5G) radio access technology, the so-called new radio (NR). The aim is to achieve the performance requirements forIMT-2020 radio interface technology. In this paper, we focus on the analysis of the transmission of 5G NR uplink physical channels, such as physical uplink shared channel (PUSCH) and physical uplink control channel (PUCCH), dedicated for data and control channels, respectively, as specified in the 3GPP standard, using digital signal processing (DSP)-assisted frequency division multiple access (FDMA) and time division multiple access (TDMA) channel aggregation techniques on an analogue radio-over-fiber (A-RoF) architecture. We verified that there is ~34% spectral efficiency gain and lower error vector magnitude (EVM) achieved using the TDMA technique.

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Martynov, Gleb V., Elena A. Morina, Aleksey I. Makarov, Daria E. Monastyreva, Zaur S. Daurov, and Roman S. Tikhonov. "Bolt attachments of composite materials under conditions of climatic ageing." Vestnik MGSU, no. 7 (July 2019): 852–61. http://dx.doi.org/10.22227/1997-0935.2019.7.852-861.

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Introduction: the glass-fibre reinforced plastic (GFRP) is a composite material that found wide application in construction due to its unique properties. One of the techniques of joining composite units is a bolt attachment that is distinguished by its stability and manufacturability. Owing to relative novelty of the material, there is no comprehensive experimental database and it is impossible to define the corresponding reliability coefficients. The given problem can be solved by means of accelerated climatic tests, which will replace multi-year observation over the installations and will allow conducting precise calculations during design work right nowadays. Materials and methods: the climatic tests were conducted over samples fabricated from polymeric structural pultrusion profile GFRP for construction purposes produced by Research-and-Production Enterprise ApATeCh (Moscow). The samples were fabricated from a single batch of U-channel 388 × 120 × 10/12 (SPPS-340). The test method consists in sequential cyclic exposure of artificially created system of climatic factors (elevated air temperature and humidity, negative temperature, temperature gradients) to the tested samples and determination of material property variations under the described impacts in the main indicators or the indicator responsible for workability of the material. Results: the obtained data were processed and the strength-time variation dependences were presented in graphic form. Using approximating dependences, the strength reduction coefficients of the bolt attachment were calculated for 100-year thermomoist exposure. Conclusions: any significant influence of ultraviolet exposure to strength of the bolt attachments was not revealed. 100-year thermomoist exposure will reduce the bolt attachment strength by not more than one third. One can recommend to introduce revisions in normative documents including reduction of reliability coefficient K2, allowing for GFRP maintenance ageing, from 1.2 to 1.13 in company standard “Road and construction structures from composite materials”.

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Islam, Tadbirul, and Mohammad Nasir Uddin. "High Speed OTDM-DWDM Bit Compressed Network for Long-Haul Communication." AIUB Journal of Science and Engineering (AJSE) 18, no. 2 (August 31, 2019): 57–65. http://dx.doi.org/10.53799/ajse.v18i2.41.

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This paper represents an optical communication network design that incorporates both OTDM and DWDM techniques which provides up to 240 Gbit/s data transfer rate, long-haul communication distance of 2700 km with a maximum number of 384 channels in this designed architecture. Each channel has a bitrate of 625 Mbit/s that follows optical signal hierarchy OC-12, STS-12 (SONET ANSI), and STM-4 (SDH CCITT), and the design maintains standard parameters for commercially available channel grids at 100 GHz spacing. The communication is done by Single Mode Fiber (SMF) of 50 km and Dispersion Compensating Fiber (DCF) of 10 km followed by one optical amplifier gain in each span. Bit error rate (BER) remains significantly low while transmission distance for only OTDM is 18000 km at a BER < 10-12, and for the hybrid OTDM-DWDM it is 2700 km at a BER < 10-16. Both values are measured under 128 bits sequence length. Three compression stages are used for 8 channels each in order to minimize the gap between bits, and to utilize the space for more channels within a specific time window.

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Hwang, G. S., U. S. Pyun, Y. Chung, B. W. Kim, and J. S. Lee. "WDM channels over 2000 km of standard singlemode fibre." Electronics Letters 43, no. 16 (2007): 889. http://dx.doi.org/10.1049/el:20071163.

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Bauke, Stephan, Kai Golibrzuch, Frank Rotter, Hainer Wackerbarth, Olaf Thiele, and Thomas Berg. "Quantitative, time-resolved detection of CH<sub>4</sub> concentrations in flows for injection analysis in CNG engines using IR absorption." Journal of Sensors and Sensor Systems 6, no. 1 (May 8, 2017): 185–98. http://dx.doi.org/10.5194/jsss-6-185-2017.

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Abstract. The reduction of CO2 and other greenhouse gas emissions is an important driving force for the development of modern engines. Especially in the transport sector, the use of alternative fuels like methane, the main component of compressed natural gas (CNG), is an applied measure to achieve this goal. This work describes the development of an optical measurement system for accurate quantification of CH4 densities in gas flows based on broadband absorption of infrared light, i.e. non-dispersive IR absorption spectroscopy (NDIR). We demonstrate the capability of the system to achieve high time resolution as well as high measurement accuracy and precision. The optical set-up of the system is designed for usage at the inlet manifold of CNG-fuelled spark ignition engines. It allows for detailed analysis of the mixture formation during single engine cycles. CH4 densities can be determined by monitoring the infrared light attenuation around 3.3 µm caused by the ν3 anti-symmetric C–H-stretch vibration. We calculate the nonlinear relation between transmittance and CH4 density from absorption cross sections calculated from the HITRAN database. The theoretical transmittance signals are corrected for spectral influences of the bandpass filter, the detector sensitivity, the fibre transmittance and the emission spectrum of the light source in order to calculate CH4 densities directly from the measured transmittance. A calibration function corrects remaining differences between experimental and simulated values and improves the accuracy. We show that the sensor system is capable for determination of air–fuel ratios (λ-values) and demonstrate the dynamic quantification of a CH4 injection into a flow channel under various flow conditions. Furthermore, we present the first measurements with a prototype probe capable of measurements inside the inlet manifold of a four-stroke spark ignition engine. We validate the detection strategy in experiments with premixed gases using a modified inlet geometry and demonstrate its application under standard engine operation with port fuel injection while varying the injection parameters.

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Ali, Riyam Saadi, Ali Y. Fattah, and Mustafa D. Hassib. "The effects of optical fiber impairments on communication systems." Indonesian Journal of Electrical Engineering and Computer Science 28, no. 1 (October 1, 2022): 241. http://dx.doi.org/10.11591/ijeecs.v28.i1.pp241-253.

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In this paper, the influence of physical layer impairments on fiber optic channels was evaluated using analytical modeling, and the findings were verified through simulation results. Light propagation inside standard single mode fiber (SSMF) is affected by both linear and nonlinear effects, which must be taken into account in order to develop an appropriate fiber channel model. The use of nonlinear fiber optics in the implementation of highcapacity optical networks is crucial. The "Optisystem 17.0" software package was used to simulate the suggested systems. It can be observed that increased input power tends to increase the effect of cross-phase modulation (XPM) and four wave mixing (FWM) in the nonlinear dispersive fibers. The impact of pulse broadening due to chromatic dispersion (CD), self-phase modulation (SPM), and cross-phase modulation (XPM) was investigated using Gaussian pulses as input signals.

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Muflikhun, Muhammad Akhsin, Seno Darmanto, Alvin Dio Nugroho, Nur Kholis Fathurrohman, Imam Saputra, and Muhammad Kusni. "ANALYSIS OF COCONUT FIBER REINFORCED COMPOSITES WITH HOT PRESS TECHNIQUES." Jurnal Rekayasa Mesin 15, no. 1 (May 15, 2024): 157–66. http://dx.doi.org/10.21776/jrm.v15i1.1452.

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Natural fibre waste is a material with high material resistance, including fibres derived from coconut fruit. Coconut fruit waste is frequently underutilised and can contribute to environmental pollution if not handled correctly. This study's objective is to convert waste from coconuts into fibres, incorporate them into composite mixtures, and produce robust materials. Using coconut fibre presents a significant advantage in that it is easily biodegradable, reducing environmental pollution. The aim of this research is to produce a composite board material using HDPE plastic and coconut fibre, which is resistant to corrosion, through the hot felting method. This method of producing composite materials results in minimal voids and high material density, effectively reducing the chances of material failure. The composite specimens were subjected to testing following the ASTM D 638-01 standard. Technical abbreviations used throughout the text will be explained upon first use. The study achieved an excellent average tensile strength, strain, and elastic modulus of 22.45 MPa, 7.15%, and 5.13 MPa, respectively. The manufacture of composite materials using coconut coir fibre combined with HDPE plastic through the hot felting method resulted in high material strength, corrosion resistance, and reprocessability.

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Karpeev, Sergey V., Vladimir V. Podlipnov, Svetlana N. Khonina, Nikolay A. Ivliev, and Sofia V. Ganchevskay. "Free-Space Transmission and Detection of Variously Polarized Near-IR Beams Using Standard Communication Systems with Embedded Singular Phase Structures." Sensors 22, no. 3 (January 24, 2022): 890. http://dx.doi.org/10.3390/s22030890.

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We propose to achieve multichannel information transmission in free space by means of variously polarized beams. The interaction of vortex beams of various orders with the main polarization states is theoretically analyzed. The passage of beams with different polarization states through multi-order diffractive optical elements (DOEs) is simulated numerically. Using the simulation results, tables of code correspondence of diffraction order numbers to the presence of phase vortices in the analyzed beams are constructed, which allow one to determine diffraction orders that carry information about various polarization states. The performed experiment made it possible to study the recognition of the first order cylindrical polarization state formed by a Q-plate converter using a phase DOE. In the experiment, these elements were built into a commercial fiber-optic communication system operating at the near-IR frequencies. After detecting the beam polarization state, beams of the required diffraction orders are efficiently coupled into optical fiber using an additional phase element. The developed optical detection system also provides channel suppression of homogeneously polarized components, which are supposed to be used for transmission of other channels.

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Wu, Ben, and Yue-Kai Huang. "Optical-Amplifier-Compatible Long-Distance Secure Key Generation Based on Random Phase Fluctuations for WDM Systems." Sensors 20, no. 21 (November 5, 2020): 6296. http://dx.doi.org/10.3390/s20216296.

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We proposed and experimentally demonstrated a secure key generation and distribution system that is compatible with optical amplifiers and standard wavelength-division multiplexing (WDM) transmission systems. The key is generated from the phase fluctuations induced by environmental instabilities. The key generation system is tested in a 240 km bidirectional fiber-pair link with multiple optical amplifiers. To demonstrate the compatibility with WDM systems, 38 WDM channels are transmitted together with the key distribution channel. The secret key is protected against eavesdropping and coherence detection attack by the wide-band property of the signal carrier and the fast-changing rate of the phase fluctuations.

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Yaroslavskyy, Ya, S. Pavlov, S. Kostyuk, and S. Tymchyk. "Principles of Building Telemedicine Networks and Systems Based on Fiber-Optic Communication Channels in Vinnytsia Region." Optoelectronic Information-Power Technologies 42, no. 2 (October 26, 2022): 84–95. http://dx.doi.org/10.31649/1681-7893-2021-42-2-84-95.

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The article draws a conclusion using the biblio-semantic approach regarding the perspective of creating optoelectronic networks for the exchange of telemedical data, formulated a range of unsolved problems and identified the main directions of their development. The development based on the model of the telemedical data transmission information channel of the fiber-optic communication channel for the exchange of telemedical information with the additional introduction to its structure of optical amplifiers with automatic gain control (AMP) and the unit of automatic control and diagnostics of the optical cable provided remote control with state determination cable fibers; automatic diagnosis of the condition of the cable with an accurate determination of the location and nature of the damage, linking of reflectors to the geographical map of the area and analysis of changes in the parameters of the VOKZ over time, which ultimately increased the reliability and improved the quality of the transmission of biomedical information. automatic . The development of a fiber-optic telemedicine network for the exchange of operational results of telemedical diagnostics and health monitoring of patients in remote areas of the Vinnytsia region through fiber-optic communication channels will in the future ensure its adaptation to the DICOM standard, information support for decision-making, and a flexible work management system network in compliance with the requirements for the protection of personal data of patients.

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Russell, Greg, Silvia N. W. Hertzberg, Natalia Anisimova, Natalia Gavrilova, Beáta É. Petrovski, and Goran Petrovski. "Digital Image Analysis of the Angle and Optic Nerve: A Simple, Fast, and Low-Cost Method for Glaucoma Assessment." Journal of Ophthalmology 2020 (October 28, 2020): 1–8. http://dx.doi.org/10.1155/2020/3595610.

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Purpose. To devise a simple, fast, and low-cost method for glaucoma assessment using digital image analysis of the angle and optic nerve in human subjects. Methods. Images from glaucoma and fundus assessment were used in this study, including color fundus photographs, standard optic nerve optical coherence tomography (OCT), and digital slit-lamp images of the angle/gonioscopy. Digital image conversion and analysis of the angle using ImageJ (NIH, USA) and adaptive histogram equalization contrast-limited AHE (CLAHE) to prevent noise amplification were implemented. Angle and optic nerve images were analyzed separately in the red, green, and blue (RGB) channels followed by 3D volumetric analysis of the degrees of angle depth and cup volume of the optic nerve. Horizontal tomogram reconstitution and nerve fiber detection methods were developed and compared to standard OCT images. Results. Digital slit-lamp angle images showed similar accuracy as standard anterior OCT measurements. Comparative analysis of RGB channels produced volumetric cup and horizontal tomogram, which closely resembled the 3D OCT appearance and B-scan of the cup, respectively. RGB channel splitting and image subtraction produced a map closely resembling that of the retinal nerve fiber layer (RNFL) thickness map on OCT. Conclusions. While OCT imaging is rapidly progressing in the area of optic disc and chamber angle assessment, rising healthcare costs and lack of availability of the technology open a demand for alternative and cost-minimizing forms of image analysis in glaucoma. Volumetric, geometric, and segmentational data obtained through digital image analysis correspond well to those obtained by OCT imaging.

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Liu, Yifan, Zhisen Zhang, Panpan Yu, Yijing Wu, Ziqiang Wang, Yinmei Li, Wen Liu, and Lei Gong. "Learning-enabled recovering scattered data from twisted light transmitted through a long standard multimode fiber." Applied Physics Letters 120, no. 13 (March 28, 2022): 131101. http://dx.doi.org/10.1063/5.0087783.

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Multiplexing multiple orbital angular momentum (OAM) modes of light has proven to be an effective way to increase data capacity in fiber-optic communications. However, existing techniques for distributing the OAM modes rely on specially designed fibers or couplers. Direct transmission of multiplexed OAM modes through a long standard multimode fiber remains challenging because the strong mode coupling in fibers disables OAM demultiplexing. Here, we propose a deep-learning-based approach to recover the scattered data from multiplexed OAM channels without measuring any phase information. Over a 1-km-long standard multimode fiber, our method is able to identify different OAM modes with an accuracy of more than 99.9% in the parallel demultiplexing of 24 scattered OAM channels. To demonstrate the transmission quality, color images are encoded in multiplexed twisted light and our method achieves decoding the transmitted data with an error rate of 0.13%. Our work shows that the artificial intelligence algorithm could benefit the use of OAM multiplexing in commercial fiber networks and high-performance optical communication in turbulent environments.

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Yaroslavskyy, Ya, S. Pavlov, S. Kostyuk, and S. Tymchyk. "Fiber-optical technologies for information (internet, intranet etc.) and energy networks." Optoelectronic Information-Power Technologies 42, no. 2 (October 26, 2022): 84–95. http://dx.doi.org/10.31649/1681-7893-2021-41-1-84-95.

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The article draws a conclusion using the biblio-semantic approach regarding theperspective of creating optoelectronic networks for the exchange of telemedical data, formulateda range of unsolved problems and identified the main directions of their development. Thedevelopment based on the model of the telemedical data transmission information channel of thefiber-optic communication channel for the exchange of telemedical information with theadditional introduction to its structure of optical amplifiers with automatic gain control(AMP) and the unit of automatic control and diagnostics of the optical cable provided remotecontrol with state determination cable fibers; automatic diagnosis of the condition of the cablewith an accurate determination of the location and nature of the damage, linking of reflectors tothe geographical map of the area and analysis of changes in the parameters of the VOKZ overtime, which ultimately increased the reliability and improved the quality of the transmission ofbiomedical information. automatic . The development of a fiber-optic telemedicine network forthe exchange of operational results of telemedical diagnostics and health monitoring of patientsin remote areas of the Vinnytsia region through fiber-optic communication channels will in thefuture ensure its adaptation to the DICOM standard, information support for decision-making,and a flexible work management system network in compliance with the requirements for theprotection of personal data of patients.

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Mariam lazem, Ali Mahdi Hammadi, and Ali Al-Askery. "Improve Quality Factor by Using DWDM Technology for Long Distances and Different Power Levels." Journal of Techniques 4, no. 4 (December 31, 2022): 12–23. http://dx.doi.org/10.51173/jt.v4i4.588.

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In optical fiber communications, data travels from the transmitter to the receiver, where it is collected and converted from optical pulses into electrical signals. The need for bandwidth has grown significantly in recent years. Dense Wavelength Division Multiplexing (DWDM), an advanced multiplexing technology that allows multiple signals to be delivered simultaneously at different wavelengths in the same channel, has been developed to meet the demand for higher capacity and faster data rates. There is a decrease in signal quality as a result of the pulse expansion caused by the scattering. During long-distance transportation, scattering should be minimized. In this research, The DWDM link model uses OptiSystem 18. The DWDM design uses 48 channels, 200 GHz channel spacing, and a bit rate of 40 Gbps for each channel The link length used is 240 and 300 km, using SMF (Single Fiber Mode) and DCF (Dispersion Compensation Amplifier). The research was performed with differences in laser power of 0, 3, and 5 dBm. From the results of the analysis carried out, changes in power changes affect the performance of the system using the MRZ (Mach Zander rate) produced by a CW-10 dB laser. The laser power values correspond to the standard Q-factor and BER (Bit Error Rate) values. The highest Q-factor is 23.266 and BER is 4.66232e-0120, while the lowest Q-factor is 14.9477 and BER is 7.89923e-051. Research has shown The more laser power is used, the better the system's performance.

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Xiang, Changqing, Xi Yang, Xuan Zhou, Xiaojun Zhu, Jincan Xu, and Qiong He. "Improved Training Sequence Channel Estimation Scheme in 16QAM MB-OFDM UWBoF System." Advances in Condensed Matter Physics 2020 (October 13, 2020): 1–7. http://dx.doi.org/10.1155/2020/6273892.

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In this paper, an improved channel estimation scheme based on time-domain orthogonal gray complementary training sequence (Golay TS) is proposed to resist subcarrier mutual beat interference in 16-quadrature amplitude modulation multiband orthogonal-frequency-division-multiplexing ultrawide band over fiber (16QAM MB-OFDM UWBoF) systems. The simulation results showed that the performance of system with the improved Golay TS channel estimation scheme was improved by about 1 dB compared with the traditional Golay TS channel estimation scheme, at a bit error rate (BER) of 3.8 × 10−3 after 70 km standard single mode fiber (SSMF) transmission. At the same time, the synchronization and channel estimation performance of Golay TS and the selected frequency-domain orthogonal training sequences (TSs) were compared. The simulation results showed that the performance of system with the TSs channel estimation was improved by about 2.7 dB compared with the improved Golay TS channel estimation.

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Ho, Angela W. H., and W. Y. Ip. "Biocompatibility and Efficacy of Five-Channel and Eight-Channel Crosslinked Urethane-Doped Polyester Elastomers (CUPEs) as Nerve Guidance Conduit for Reconstruction of Segmental Peripheral Nerve Defect Using Rat Model." Journal of Biomimetics, Biomaterials and Biomedical Engineering 21 (August 2014): 57–70. http://dx.doi.org/10.4028/www.scientific.net/jbbbe.21.57.

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Introduction: Peripheral nerve injury is common in clinical practice. Nerve defect is a challenging scenario. The current gold standard of managing a nerve defect is autologous nerve graft. However, due to the selection of nerve graft and donor site morbidity, artificial nerve conduits are gaining popularity. However, there are drawbacks of single hollow conduit such as lack of internal support to prevent conduit collapse and inability so as to recreate the proper native spatial arrangement of cells and extracellular matrix within the conduit. In this study, the biocompatibility and efficacy of five-channel and eight-channel Crosslinked Urethane-doped Polyester Elastomers (CUPEs) as nerve guidance conduit will be evaluated through a rat model with reconstruction of segmental peripheral nerve defect. Material and Method: Eighteen adult Sprague-Dawley rats were used. They were randomly allocated to three groups: autograft group, five-channel conduit group and eight-channel conduit group with each consisted of six rats. A 10mm nerve defects were created at the right sciatic nerve. They were bridged with reverse autograft, 5-channel conduit and 8-channel conduit. After eight weeks the rats were euthanized and the reconstructed nerves were harvested for histomorphometric analysis. Result: All conduits showed regenerated nerve tissue inside. There was no collapse of the conduits. There were no severe tissue reaction or scarring near the reconstructed nerve. No neuroma was formed. Histomorphometric analysis showed nerve regeneration was enhanced with increasing number of channels inside conduit. There was overall drop in fiber density between proximal and distal segment among all groups. Conclusion: CUPE nerve guidance conduit is biocompatible and shows good nerve regeneration in reconstructing nerve defect.

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Liu, Xinyu, Chao Li, Ziyun Jiang, and Lu Han. "Low-Complexity Pruned Convolutional Neural Network Based Nonlinear Equalizer in Coherent Optical Communication Systems." Electronics 12, no. 14 (July 18, 2023): 3120. http://dx.doi.org/10.3390/electronics12143120.

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Nonlinear impairments caused by devices and fiber transmission links in a coherent optical communication system can severely limit its transmission distance and achievable capacity. In this paper, we propose a low-complexity pruned-convolutional-neural-network-(CNN)-based nonlinear equalizer, to compensate nonlinear signal impairments for coherent optical communication systems. By increasing the size of the effective receptive field with an 11 × 11 large convolutional kernel, the performance of feature extraction for CNNs is enhanced and the structure of the CNN is simplified. And by performing the channel-level pruning algorithm, to prune the insignificant channels, the complexity of the CNN model is dramatically reduced. These operations could save the important component of the CNN model and reduce the model width and computation amount. The performance of the proposed CNN-based nonlinear equalizer was experimentally evaluated in a 120 Gbit/s 64-quadrature-amplitude-modulation (64-QAM) coherent optical communication system over 375 km of standard single-mode fiber (SSMF). The experimental results showed that, compared to a CNN-based nonlinear equalizer with a 6 × 6 normal convolutional kernel, the proposed CNN-based nonlinear equalizer with an 11 × 11 large convolutional kernel, after channel-level pruning, saved approximately 15.5% space complexity and 43.1% time complexity, without degrading the equalization performance. The proposed low-complexity pruned-CNN-based nonlinear equalizer has great potential for application in realistic devices and holds promising prospects for coherent optical communication systems.

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Pieper, W., R. Ludwig, C. M. Weinert, B. Kuhlow, G. Przyrembel, M. Ferstl, E. Pawlowski, and H. G. Weber. "4-channel x 40-Gb/s unrepeatered OTDM transmission over 100-km standard fiber." IEEE Photonics Technology Letters 10, no. 3 (March 1998): 451–53. http://dx.doi.org/10.1109/68.661440.

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Lebedev, V. V., K. M. Anufriev, N. V. Toguzov, I. V. Il’ichev, and A. V. Shamray. "An additional channel for FM signal transmission in standard fiber-optic AM communication lines." Technical Physics Letters 41, no. 11 (November 2015): 1083–86. http://dx.doi.org/10.1134/s1063785015110218.

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Shchelkin, Kirill E., and Gleb V. Popkov. "DETECTION OF INFORMATION LEAKAGE THREATS IN FIBER OPTICAL COMMUNICATION CHANNEL." Interexpo GEO-Siberia 6, no. 2 (July 8, 2020): 182–88. http://dx.doi.org/10.33764/2618-981x-2020-6-2-182-188.

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The paper discusses the possibility of detecting an information leakage channel in standard fiber-optic communications by monitoring optical radiation. Any abnormal light emission can create a potential threat of speech information leakage, as well as regular light streams modulated at acoustic frequencies.

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Gupta, Amit. "Comparative Analysis of Various Wavelength Division Multiplexed PON Standards." Journal of Optical Communications 40, no. 1 (January 28, 2019): 51–54. http://dx.doi.org/10.1515/joc-2017-0054.

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Abstract In this investigation comparison of various Passive optical networks (PON) standards has been done. Bidirectional fiber to home architecture is projected which simultaneously transmits the video and audio signals. The system uses travelling wave semiconductor optical amplifier with injection current of 0.45 A for both upstream and downstream channels. This architecture is investigated for a distance of 40 km and it accommodates 96 users. Further the effect of varied distance and power on Q-factor of system is investigated.

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Anbarasu, M., M. Kasiviswanathan, M. Kathiresan, and G. Mohan Ganesh. "Numerical Parametric Study and Design of Pultruded GFRP Composite Channel Columns." Sustainability 15, no. 1 (January 3, 2023): 837. http://dx.doi.org/10.3390/su15010837.

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This article reports the finite element (FE) investigation of the axial capacities of pultruded fiber-reinforced polymer (PFRP) composite channel columns. The nonlinear finite element model (FEM) was developed by using the ABAQUS package for glass fiber-reinforced polymer (GFRP) composite channel columns, which included geometric and initial geometric imperfections. The developed FEMs were verified against an experimental result available in the literature for GFRP channel columns. The validated FEMs were used to carry out the parametric study comprising 61 FE models to investigate the effect of different geometries, plate slenderness and the length of members on the axial capacities of GFRP pultruded channel columns. The results obtained from the parametric study were used to examine the accuracy of the current Italian guidelines, American pre-standard and the Direct Strength Method (DSM) proposed in the literature for GFRP channel profiles. Based on the obtained results, the suitability of the current design guidelines is assessed and, also, a new set of design equations is proposed to estimate the axial capacity of the pultruded GFRP channel columns. The new proposed set of reliable design equations witnessed a less scattered and a high degree of accuracy in determining the axial load capacity of the pultruded GFRP composite channel columns.

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Xiao, Yue Yu, and Hong Wei Wang. "Refractive Index Sensors Based Resonant Coupling in Solid-Core Photonic Band-Gap Fibers." Advanced Materials Research 753-755 (August 2013): 2103–6. http://dx.doi.org/10.4028/www.scientific.net/amr.753-755.2103.

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A novel refractive index sensor based on the resonant coupling mechanism is proposed. The sensor consists of a standard index-guiding solid fiber core and several periodically distributed micro fluidic channels. When the channels are infiltrated with high-index fluid, the resonant coupling between the core mode and cladding modes makes the sensing fiber to be a stop-band filter. Since the filtering effect introduced by the photonic band-gap of the cladding is sensitive to the refractive index of the measurand, numerical results reveal that the sensitivity of the sensor could reach 17250nm/RIU, which is much higher than traditional refractive index fiber sensors.

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Yu, Ronghua, Qichao Wang, Guangyao Dai, Xiangcheng Chen, Chao Ren, Jintao Liu, Dongrui Li, et al. "The Design and Performance Evaluation of a 1550 nm All-Fiber Dual-Polarization Coherent Doppler Lidar for Atmospheric Aerosol Measurements." Remote Sensing 15, no. 22 (November 13, 2023): 5336. http://dx.doi.org/10.3390/rs15225336.

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A 1550 nm all-fiber dual-polarization coherent Doppler lidar (DPCDL) was constructed to measure the depolarization ratio of atmospheric aerosols. In lidar systems, the polarization state of the laser source is typically required to be that of linearly parallel polarization. However, due to the influence of the fiber-optical transmission and the large-mode field output of the telescope, the laser polarization state changes. Hence, a polarizer was mounted to the emitting channel of the telescope to eliminate the depolarization effect. A fiber-optical polarization beam splitter divided the backscattered light into components with parallel and perpendicular polarization. The DPCDL used two coherent channels to receive each of these two polarization components. A calibration procedure was designed for the depolarization ratio to determine the differences in gain and non-responsiveness in the two polarization channels. The calibration factor was found to be 1.13. Additionally, the systematic error and the measured random error of the DPCDL were estimated to evaluate the performance of the system. The DPCDL’s systematic error was found to be about 0.0024, and the standard deviation was lower than 0.0048. The Allan deviations of a 1-min averaging window with a low SNR of 19 dB and a high SNR of 27 dB were 0.0104 and 0.0031, respectively. The random errors at different measured heights were mainly distributed below 0.015. To confirm the authenticity of the atmospheric depolarization ratio measured with the DPCDL, two field observations were conducted with the use of a co-located DPCDL and micro-pulse polarization lidar to perform a comparison. The results showed that the correlation coefficients of the aerosol depolarization ratios were 0.73 and 0.77, respectively. Moreover, the two continuous observations demonstrated the robustness and stability of the DPCDL. The depolarization ratios were detected in different weather conditions.

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Piana Agostinetti, Nicola, Alberto Villa, and Gilberto Saccorotti. "Distributed acoustic sensing as a tool for subsurface mapping and seismic event monitoring: a proof of concept." Solid Earth 13, no. 2 (March 3, 2022): 449–68. http://dx.doi.org/10.5194/se-13-449-2022.

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Abstract. We use PoroTomo experimental data to compare the performance of distributed acoustic sensing (DAS) and geophone observations in retrieving data to execute standard subsurface mapping and seismic monitoring activities. The PoroTomo experiment consists of two “seismic systems”: (a) a 8.6 km long optical fibre cable deployed across the Brady geothermal field and covering an area of 1.5 × 0.5 km with 100 m long segments and (b) a co-located array of 238 geophones with an average spacing of 60 m. The PoroTomo experiment recorded continuous seismic data between 10 and 25 March 2016. During this period, a Ml 4.3 regional event occurred in the southeast, about 150 km away from the geothermal field, together with several microseismic local events related to the geothermal activity. The seismic waves generated from such seismic events have been used as input data in this study to tackle similarities and differences between DAS and geophone recordings of such wavefronts. To assess the quality of data for subsurface mapping tasks, we measure the propagation of the P wave generated by the regional event across the geothermal field in both seismic systems in term of relative time delays, for a number of configurations and segments. Additionally, we analyse and compare the amplitude and the signal-to-noise ratio (SNR) of the P wave in the two systems at high resolution. For testing the potential of DAS data in seismic event locations, we first perform an analysis of the geophone data to retrieve a reference location of a microseismic event, based on expert opinion. Then, we a adopt different workflow for the automatic location of the same microseismic event using DAS data. To assess the quality of the data for tasks related to monitoring distant events, we retrieve both the propagation direction and apparent velocity of the wave field generated by the Ml 4.3 regional event, using a standard plane-wave-fitting approach applied to DAS data. Our results indicate that (1) at a local scale, the seismic P-wave propagation (i.e. time delays) and their characteristics (i.e. SNR and amplitude) along a single cable segment are robustly consistent with recordings from co-located geophones (delay times δt∼0.3 over 400 m for both seismic systems); (2) the DAS and nodal arrays are in mutual agreement when it comes to site amplifications, but it is not immediately clear which geological features are responsible for these amplifications. DAS could therefore hold potential for detailed mapping of shallow subsurface heterogeneities, but with the currently available information of the Brady Hot Springs subsurface geology, this potential cannot be quantitatively verified; (3) the interpretation of seismic wave propagation across multiple separated segments is less clear due to the heavy contamination of scattering sources and local velocity heterogeneities; nonetheless, results from the plane-wave-fitting approach still indicate the possibility for a consistent detection and location of the distant event; (4) automatic monitoring of microseismicity can be performed with DAS recordings with results comparable to manual analysis of geophone recordings in the case of events within or close to the DAS system (i.e. maximum horizontal error on event location around 70 m for both geophone and DAS data); and (5) DAS data preconditioning (e.g. temporal subsampling and channel stacking) and dedicated processing techniques are strictly necessary for making seismic monitoring procedures feasible and trustable.

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Koretsky, E., S. Shevkun, M. Golovnya, O. Mesheryak, V. Bojko, A. Gavrilov, M. Svitenko, and M. Trotsko. "Problems and Ways to take Objectives with the Control and Management by the Transmission of Ethnic Time and Frequency Signals in the Armed Forces of Ukraine." Metrology and instruments, no. 2 (May 3, 2019): 57–61. http://dx.doi.org/10.33955/2307-2180(2)2019.57-61.

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Within the limits of the functioning of the military segment of the single time service and reference frequencies, the problems and ways of solving the tasks of controlling and controlling the transmission of reference signals used by the Armed Forces of Ukraine are outlined. The experimental research on the determination of the accuracy characteristics of the time synchronization system (using the PTP protocol IEEE 1588v2) was implemented for its use in telecommunication networks. As a communication channel, an optical fiber network is specially built to create a synchronization system. Experimental studies confirmed the possibility of transmitting reference signals of time and frequency synchronization with the use of modern digital and fiber-optic technologies from the National Standard of Time and Frequency units to the source standard of the Armed Forces of Ukraine units of time and frequency (VEZSU) with an error that is not exceeds 1 цs And also from VESZU to consumers with an error of less than 10 microseconds at a distance of 600 km via fiber-optic communication channel L2. The creation of a corresponding complex of equipment for monitoring and control of the transmission of reference signals used by the Armed Forces of Ukraine remains relevant.

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Ghanbarisabagh, Mohammad, Nasreddine Maloulki, and Bechir Nsiri. "Efficiency Improvement for Optical OFDM Systems." International Journal of Information and Communication Sciences 1, no. 2 (September 30, 2016): 35–38. http://dx.doi.org/10.11648/j.ijics.20160102.14.

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The evaluation of Optical Orthogonal Frequency Division Multiplexing (OOFDM) using Least Mean Square Time-domain Equalizer (LMSTE), Recursive Least Squares-Time-domain Equalizer (RLSTE) and Decision Feedback Time-domain Equalizer (DFTE) to reduce Cyclic Prefix (CP) length over 1200 Km of Standard Single Mode Fiber (SSMF) is presented. All of these TEQs are used immediately after the fiber channel. They can cancel the residual Inter Symbol Interference (ISI) and Inter Carrier Interference (ICI) caused by both the Group Velocity Dispersion (GVD) and the CP length being shorter than the Channel Impulse Response (CIR). Using these TEQs allow the reduction in size of CP, and consequently leading to system performance improvement. DFTE can decrease the noise whereas RLSTE can achieve a higher convergence and better performance compared to LMSTE.

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Kesawan, Sivakumar, and Mahen Mahendran. "Fire performance of LSF walls made of hollow flange channel studs." Journal of Structural Fire Engineering 8, no. 2 (June 12, 2017): 149–80. http://dx.doi.org/10.1108/jsfe-03-2017-0027.

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Purpose This paper aims to present an investigation conducted to evaluate the effects of important parameters affecting the structural fire performance of light gauge steel frame (LSF) walls. It also evaluates the applicability of commonly used critical hot flange temperature method to determine the fire resistance ratings (FRR) of different LSF walls. Design/methodology/approach The effects of important parameters such as stud section profiles and their dimensions, elevated temperature mechanical property reduction factors of the steel used, types of wall configurations and fire curves on the FRR of LSF walls were investigated. An extensive finite element analysis-based parametric study was conducted to evaluate their effects (finite element analysis – FEA). For this purpose, finite element models which were validated using the full-scale fire test results were used. Using the structural capacities obtained from FEAs, the load ratio versus FRR curves were produced for all the different LSF walls considered. Findings Stud depth and thickness significantly affected the fire performance of LSF walls because of the differences in temperature development pattern, thermal bowing deflections and the failure modes of stud. The FRR of LSF walls increased significantly when steel studs with higher elevated temperature mechanical property reduction factors were used. FRR significantly changed when realistic design fire curves were used instead of the standard fire curve. Furthermore, both the critical hot and average flange temperature methods were found to be unsuitable to predict the FRR of LSF walls. Originality/value The developed comprehensive fire performance data would facilitate the development of LSF walls with enhanced fire performance, and, importantly, it would facilitate and advance the successful applications of hollow flange channel section studs in LSF walls.

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Navarrini, Alessandro, Alessandro Scalambra, Simone Rusticelli, Andrea Maccaferri, Alessandro Cattani, Federico Perini, Pierluigi Ortu, et al. "The Room Temperature Multi-Channel Heterodyne Receiver Section of the PHAROS2 Phased Array Feed." Electronics 8, no. 6 (June 12, 2019): 666. http://dx.doi.org/10.3390/electronics8060666.

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This paper describes the design, fabrication, and test results of a room temperature multi-channel heterodyne receiver operating across the 2.3–8.2 GHz radio frequency (RF) band. Such a “Warm Section” (WS) receiver is part of phased arrays for reflector observing systems 2 (PHAROS2), a C-band phased array feed (PAF) demonstrator with digital beamformer for radio astronomy application. The WS receiver is cascaded to the PHAROS2 cryostat, which includes an array of Vivaldi antennas with low noise pre-amplification stages. The WS can handle up to 32 RF signals and, for each of them, realizes the operations of filtering, RF amplification and down-conversion from the RF to the 375–650 MHz intermediate frequency (IF). Also, the WS incorporates an IF-to-optical signal conversion through analogue wavelength division multiplexing IF over fiber (IFoF) and fiber-optic transmitters (OTXs). The 32-channel WS receiver consists of four eight-channel WS RF/IF modules, one local oscillator (LO) splitter module and one monitoring and control module, all hosted in a standard 6U × 19-inch rack.

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Cuevas-Terrones, Rodrigo, Josefina Castañeda-Camacho, Germán Ardul Muñoz-Hernández, and Ignacio Enrique Zaldívar-Huerta. "Evaluation of the Digital Data Performance Transmission on a Fiber-Radio System." Electronics 12, no. 2 (January 11, 2023): 378. http://dx.doi.org/10.3390/electronics12020378.

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This work shows a set of numerical simulations to evaluate the digital data performance transmission for a fiber-radio system. For this goal, VPI Photonics software is used to simulate the transmission of a digital signal at a bit rate of 2.4 GHz through an optical link of 25 km of single-mode standard fiber (SM-SF). Whereas MATLAB software is utilized to emulate a wireless channel considering four main phenomena inherent to this channel, such as multipath and slow fading, co-channel interference, and additive white Gaussian noise (AWGN). The modeling carried out in MATLAB considers a user in movement within its coverage area cell. The constellation diagram, bit error rate (BER), and signal-to-interference-plus-noise ratio (SINR) statistical tests are used to evaluate the performance of this approach. This proposal finds potential applications in the field of cellular telephony, the Internet of Things (IoT), or any other communication system to evaluate the quality of the delivered signal to a user in motion within a particular coverage cell.

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Journal articles on the topic 'Fibre Channel (Standard)'

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