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    Abstract:
    We demonstrate combined wavelength- and mode-multiplexed transmission with a spectral efficiency of 58 b/s/Hz over an 87-km single-span multi-mode fiber using 16-QAM modulation format. The hybrid fiber span comprises 10- and 15-mode fibers.
    Keywords:
    Modulation (music)
    Mode (computer interface)
    Spectral Efficiency
    Based on the explanation of Wavelength Division Multiplexing(WDM)concept,the concepts and technical characteristics of Dense Wavelength Division Multiplexing(DWDM)and Coarse Wavelength Division Multiplexing(CWDM)are introduced in this paper. The advantages of CWDM technology and its cost applied in BIP-MAN are analyzed and compared. The status and functions of CWDM in BIP-MAN are discussed finally.
    Citations (0)
    Spiro[fluorene-9,9′-xanthene] has received great attention due to its unique structure and possesses wide applications in the field of material chemistry.Herein, we highlighted low-cost, stable and high-performance spiro[fluorene-9,9′-xanthene] derivatives for organic electronics.
    Life span
    Attention span
    Citations (0)
    Abstract. Unmanned aerial vehicles (UAVs) provide a cost-effective way to fill in gaps between surface in situ observations and remotely sensed data from space. In this study, a novel portable CO2 measuring system suitable for operations on board small-sized UAVs has been developed and validated. It is based on a low-cost commercial nondispersive near-infrared (NDIR) CO2 sensor (Senseair AB, Sweden), with a total weight of 1058 g, including batteries. The system performs in situ measurements autonomously, allowing for its integration into various platforms. Accuracy and linearity tests in the lab showed that the precision remains within ± 1 ppm (1σ) at 1 Hz. Corrections due to temperature and pressure changes were applied following environmental chamber experiments. The accuracy of the system in the field was validated against a reference instrument (Picarro, USA) on board a piloted aircraft and it was found to be ± 2 ppm (1σ) at 1 Hz and ± 1 ppm (1σ) at 1 min. Due to its fast response, the system has the capacity to measure CO2 mole fraction changes at 1 Hz, thus allowing the monitoring of CO2 emission plumes and of the characteristics of their spatial and temporal distribution. Details of the measurement system and field implementations are described to support future UAV platform applications for atmospheric trace gas measurements.
    Linearity
    Citations (0)
    A new power efficient technique, that combines N-level multipulse pulse-position modulation with L-level quadrature-amplitude modulation, denoted by NMPPM-LQAM, is proposed. Its constrained power efficiency is derived and characterized. It is shown that the proposed combination provides a superior technique that is both power and spectral efficient simultaneously. The constrained power efficiencies of variations to this technique are considered and characterized as well. These include combining multilevel pulse-amplitude modulation with LQAM (NPAM-LQAM). The obtained constrained power efficiencies are compared numerically to that of traditional LQAM and MPPM-LQAM techniques. Our results disclose that proposed NMPPM-LQAM is the most power/spectral efficient technique. For example, at spectral efficiency constraints of 2.5 and 4.2 bs -1 /Hz/pol, the corresponding constrained power efficiencies of proposed NMPPM-LQAM technique are higher by about 4.87 and 3.62 dB, respectively, than that of traditional LQAM. In addition, the results reveal that NPAM-LQAM scheme has increased power and spectral efficiencies compared to that of traditional NPAM, but its power efficiency is less than that of traditional LQAM.
    Spectral Efficiency
    Electrical efficiency
    Modulation (music)
    QAM
    Pulse-position modulation
    Citations (3)
    Abstract. Unmanned aerial vehicles (UAVs) provide a cost-effective way to fill in gaps between surface in situ observations and remotely sensed data from space. In this study, a novel portable CO2 measuring system suitable for operations on board small-sized UAVs has been developed and validated. It is based on a low-cost commercial nondispersive near-infrared (NDIR) CO2 sensor (Senseair AB, Sweden), with a total weight of 1058 g, including batteries. The system performs in situ measurements autonomously, allowing for its integration into various platforms. Accuracy and linearity tests in the lab showed that the precision remains within ± 1 ppm (1σ) at 1 Hz. Corrections due to temperature and pressure changes were applied following environmental chamber experiments. The accuracy of the system in the field was validated against a reference instrument (Picarro, USA) on board a piloted aircraft and it was found to be ± 2 ppm (1σ) at 1 Hz and ± 1 ppm (1σ) at 1 min. Due to its fast response, the system has the capacity to measure CO2 mole fraction changes at 1 Hz, thus allowing the monitoring of CO2 emission plumes and of the characteristics of their spatial and temporal distribution. Details of the measurement system and field implementations are described to support future UAV platform applications for atmospheric trace gas measurements.
    Linearity
    Citations (0)
    In order to upgrade conventional wavelength-division-multiplexing (WDM) networks, we propose to use ultradense (UD) WDM channel groups. One UD-WDM channel group replaces one WDM channel and traverses the WDM network following the same path as the original WDM channel. We show experimentally that each conventional 100-GHz-spaced WDM channel can be upgraded in this way to have the transmission capacity of 20-40 Gb/s.
    Channel spacing
    Citations (18)
    This paper addresses the singular 1-soliton solution of the K(m, n) equation that is being considered with generalized evolution.The ansatz method will be used to extract the singular 1-soliton solution of this equation.A couple of constraint conditions will fall out in order for the singular soliton solutions to exist.Subsequently, the special cases of this equation will be studied.They are the KdV and the mKdV equations where the extended (G /G)-expansion method will be employed to extract a few nonlinear wave solutions.
    Life span
    Citations (10)
    Abstract. Unmanned aerial vehicles (UAVs) provide a cost-effective way to fill in gaps between surface in situ observations and remotely sensed data from space. In this study, a novel portable CO2 measuring system suitable for operations on board small-sized UAVs has been developed and validated. It is based on a low-cost commercial nondispersive near-infrared (NDIR) CO2 sensor (Senseair AB, Sweden), with a total weight of 1058 g, including batteries. The system performs in situ measurements autonomously, allowing for its integration into various platforms. Accuracy and linearity tests in the lab showed that the precision remains within ± 1 ppm (1σ) at 1 Hz. Corrections due to temperature and pressure changes were applied following environmental chamber experiments. The accuracy of the system in the field was validated against a reference instrument (Picarro, USA) on board a piloted aircraft and it was found to be ± 2 ppm (1σ) at 1 Hz and ± 1 ppm (1σ) at 1 min. Due to its fast response, the system has the capacity to measure CO2 mole fraction changes at 1 Hz, thus allowing the monitoring of CO2 emission plumes and of the characteristics of their spatial and temporal distribution. Details of the measurement system and field implementations are described to support future UAV platform applications for atmospheric trace gas measurements.
    Linearity
    Citations (0)
    Abstract. Unmanned aerial vehicles (UAVs) provide a cost-effective way to fill in gaps between surface in situ observations and remotely sensed data from space. In this study, a novel portable CO2 measuring system suitable for operations on board small-sized UAVs has been developed and validated. It is based on a low-cost commercial nondispersive near-infrared (NDIR) CO2 sensor (Senseair AB, Sweden), with a total weight of 1058 g, including batteries. The system performs in situ measurements autonomously, allowing for its integration into various platforms. Accuracy and linearity tests in the lab showed that the precision remains within ± 1 ppm (1σ) at 1 Hz. Corrections due to temperature and pressure changes were applied following environmental chamber experiments. The accuracy of the system in the field was validated against a reference instrument (Picarro, USA) on board a piloted aircraft and it was found to be ± 2 ppm (1σ) at 1 Hz and ± 1 ppm (1σ) at 1 min. Due to its fast response, the system has the capacity to measure CO2 mole fraction changes at 1 Hz, thus allowing the monitoring of CO2 emission plumes and of the characteristics of their spatial and temporal distribution. Details of the measurement system and field implementations are described to support future UAV platform applications for atmospheric trace gas measurements.
    Linearity
    Citations (0)