Purpose: Vision-related disorders, such as refractive errors and binocular vision issues, can cause headaches. The current study evaluates the impact of Neurolens (NL) on individuals with headaches, assessed using the Headache Impact Test (HIT) questionnaire.
Methods: Subjects (18-60 years) with good stereoacuity and a HIT score of ≥56 points were enrolled.
Proc Inst Mech Eng H
February 2024
Exposure to excessive whole-body vibration is linked to health issues and may result in increased rates of mortality and morbidity in infants. Newborn infants requiring specialized treatment at neonatal intensive care units often require transportation by road ambulance to specialized care centers, exposing the infants to potentially harmful vibration and noise. A standardized Neonatal Patient Transport System (NPTS) has been deployed in Ontario, Canada, that provides life saving equipment to patients and safe operation for the clinical care staff.
View Article and Find Full Text PDFWe address the potential application of G.654.C optical fiber for O-band transmission in the wavelength range of 1270 nm to 1330 nm.
View Article and Find Full Text PDFA few-mode transmission system is proposed using 850 nm single-mode VCSEL based transceivers over graded-index single-mode fibers for high data rate data center applications. A graded-index single-mode fiber that supports two mode groups at 850 nm window with a high modal bandwidth of 48.3 GHz·km is realized for the first time.
View Article and Find Full Text PDFEvolution of next generation wireless networks brings challenges to efficiently transmit a large amount of data from a base station to a remote antenna unit. We investigate a space division multiplexing technique that employs few mode fibers (FMFs) to transmit 3 × 3 MIMO wireless signals, aiming to employ a common digital signal processing (DSP) unit to equalize both the fiber and wireless channel. We optimize system parameters and obtain above 28 dB and 23 dB signal-to-interference and noise ratio (SINR) for 3 meters wireless systems with 500 m and 2 km FMF, which correspond to the transmission capacity of 578 Mb/s and 468 Mb/s using a 20 MHz bandwidth, respectively.
View Article and Find Full Text PDFTransmission below the cable cut-off wavelength may be a concern in some systems, especially for an optical supervisory channel (OSC) operating below the signal transmission band in systems built with G.654 fiber. In this work, we constructed a cabled span of G.
View Article and Find Full Text PDFUniversal fiber has an LP mode field diameter approximately matched to that of standard single mode fiber, while being a multimode fiber. We analyzed the dependence of the mode field diameter on the core diameter for different core delta values. Guided by the analysis, a universal fiber having a delta of 1.
View Article and Find Full Text PDFWe study long-haul Quasi-Single-mode (QSM) systems in which signals are transmitted in the fundamental modes of a few-mode fiber (FMF) while keeping other system components such as amplifiers and receivers are kept single-moded. The large-effective-area nature of the FMF fundamental modes improves system nonlinear tolerance in the expense of mode coupling along FMF transmissions which induces multi-path interference (MPI) and needs to be compensated. We analytically investigate 6-spatial-polarization mode QSM transmission systems in presence of MPI and show that in the weak coupling regime, the QSM channel is a Gaussian random process in frequency.
View Article and Find Full Text PDFWe study unrepeatered transmission of 40x256 Gb/s systems with polarization-multiplexed 16-quadrature amplitude modulation (PM-16QAM) channels using simple coherent optical system configurations. Three systems are investigated with either a homogeneous fiber span, or simple two-segment hybrid fiber designs. Each system relies primarily on ultra-low loss, very large effective area fiber, while making use of only first-order backward pumped Raman amplification and no remote optically pumped amplifier (ROPA).
View Article and Find Full Text PDFA new high bandwidth bend-insensitive MMF optimized for 1310 nm is designed and characterized. 25 Gb/s transmission over a record 820 m length using a multimode launch from an integrated SiPh transceiver at 1310 nm through the new fiber is demonstrated with a power penalty of 3.4 dB at 10(-12) BER.
View Article and Find Full Text PDFWe demonstrate the transmission of 25Gb/s multimode optical signals over a record length of 300m multimode fiber designed for high modal bandwidth at 1310nm. The power penalty is 1.8 dB at 10(-12) bit error rate level.
View Article and Find Full Text PDFWe compare the transmission performance of three different optical fibers in separate 256 Gb/s PM-16QAM systems amplified with erbium doped fiber amplifiers (EDFAs) and distributed Raman amplification. The span length in each system is 100 km. The fibers studied include standard single-mode fiber, single-mode fiber with ultra-low loss, and ultra-low loss fiber with large effective area.
View Article and Find Full Text PDFUltra-long-haul transmission at distances greater than 10,000 km is investigated for 112 Gb/s PM-QPSK signals using span lengths of 75 km and 100 km and all-Raman amplification. Two different ultra-low loss and large effective area optical fibers are studied. We demonstrate a reach length of 10,200 km for a 40 channel system using a fiber with effective area 112 μm(2) with 100 km spans, and a reach length of 13,288 km for a system with 75 km spans using a fiber with effective area of 134 μm(2).
View Article and Find Full Text PDFWe demonstrate transmission of 112 Gb/s PM-QPSK signals over a system with 200 km span lengths. Amplification is provided by hybrid backward-pumped Raman/EDFA amplifiers and reach lengths up to 6000 km for an 8 channel system and 5400 km for a 32 channel system are shown. As a means of maximizing OSNR, a simple hybrid fiber span configuration is used that combines two ultra-low loss fibers, one having very large effective area.
View Article and Find Full Text PDFThe implications of increasing the symbol rate for a given digital-to-analog converter (DAC) sampling rate are investigated by considering the generation of 112 Gbit/s PM 16-QAM signals (14 Gsym/s) using a 21 GSa/s DAC with 6-bit resolution.
View Article and Find Full Text PDFWe investigate transmission of 112 Gb/s PM-QPSK signals over 50 μm core diameter OM3 multimode fiber using the center launch approach. We demonstrate successful transmission of 16 DWDM channels over a distance of 635 km for a capacity-distance product of 1016 Tb/s-km. The limiting impairment appears due to mode coupling and multipath interference effects.
View Article and Find Full Text PDFWe propose and demonstrate a novel bandwidth measurement method for multimode fibers through measuring the bit error rate and power penalty associated with the testing system. The relationship between system performance and bandwidth limitation is established through the use of well characterized electric filters. With the calibration information, bandwidths of actual fibers were measured.
View Article and Find Full Text PDFWe investigate the performance of a maximum likelihood sequence estimation (MLSE) receiver at 10.7 Gb/s in the presence of two optical nonlinear impairments, cross-phase modulation (XPM) and stimulated Brillouin scattering (SBS). We find that the tolerance to both nonlinearities decreases with larger levels of uncompensated dispersion.
View Article and Find Full Text PDFWe demonstrate time division multiplexing (TDM) and wavelength division multiplexing/TDM (WDM/TDM) long reach 10 Gb/s passive optical network (PON) architectures of 100 km reach with no infield amplification or dispersion compensation. The purely passive nature of the 100 km systems is enabled by the use of ultra-low-loss optical fiber with average attenuation of 0.17 dB/km and downstream transmission with a 10 Gb/s signal modulated with the duobinary format.
View Article and Find Full Text PDFWe experimentally demonstrate uncompensated 8-channel wavelength division multiplexing (WDM) and single channel transmission at 10.7 Gb/s over a 470 km hybrid fiber link with in-line semiconductor optical amplifiers (SOAs). Two different forms of the duobinary modulation format are investigated and compared.
View Article and Find Full Text PDFWe experimentally study the effects of cross-phase modulation and stimulated Brillouin scattering limitations in long unrepeatered transmission systems at 10.7 Gb/s. We find significant SBS suppression in wavelength-division multiplexed systems and investigate system performance for different numbers of channels and channel spacing.
View Article and Find Full Text PDFComprehensive experimental measurement data are presented comparing the performance of an optical receiver with MLSE-EDC technology against a standard receiver for signals with uncompensated chromatic dispersion. Signals with the NRZ and duobinary modulation formats are investigated. We find that the MLSE-EDC technology provides greater uncompensated reach advantage for both formats as the allowable measured BER is increased, demonstrating the EDC technology has greatest effect and application in conjunction with strong forward error correction.
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