Nowadays, the enabling of 5G technologies has a significant interest. At the same time, fiber optical access networks, which are widely realized as passive optical networks (PONs, are considered to ...be the most appropriate candidates for enabling the 5GX-haul (x-front or back) 1, 2. Thus, the demands on the integration of radio-over-fiber (RoF) technology in PON are growing significantly. The essential part of the implementation of each new technology (including converged RoF-PON) is providing the technical requirements for this technology. That is crucial for standardization, network planning, and choice of equipment. The advantages of mathematical modeling that can ensure separate investigation of different performance affecting factors can be effectively used for this purpose. Addressing this, we focus on the improvement of the modeling of the converged RoF-PON transmission system. In the current research, we analyze the modeling of the receiver sensitivity, which is one of the significant performance-affecting factors in PONs. The main goal of the research is to investigate, does the symbol-error-rate (SER) depends on the way, how the same receiver sensitivity is ensured. Respectively, to evaluate the impact of utilizing different values of the noise and bandwidth. Such investigation is crucial for the development of the models aimed to simplify the definition of the requirements to transmission systems characteristics related to noise (e.g., sensitivity, signal-to-noise-ration (SNR)). The investigation is performed for a 3.5 GHz quadrature-amplitude-modulation orthogonal frequency division multiplexing (QAM-OFDM)RoF signal. The analysis for the different number of OFDM carriers is provided. The error vector magnitude (EVM) which is widely used for the quality assessment of QAM signals is also utilized for quality evaluation.
Many National regulatory authorities are making measurements of mobile internet access service Quality of Service parameters, but only some of them measure and evaluate signal parameters of the ...network in the Quality of Service (QoS) measurement location. Although measurement of signal parameters is not obligatory for NRAs, it should be considered that signal parameters are important for mobile network operators for finding faults in network installations.Especially important relation between the throughput and signal parameters is in 5G networks in regard to coverage examination, where throughput is directly related to the Signal interference noise ratio (SINR) parameter values reported by the user equipment. In 5G case uplink channel quality of the user equipment can be indicated by SINR, but to test it, relation between other indicators such as reference signal receive power and transmit power of user equipment should be calculated. Relation and dependency between signal parameter values and Quality of Service parameters values should be evaluated from the regulatory perspective, as for choosing the appropriate measurement geographical location, as for further information for the operators, indicating the possible problems in the networks in specific geographical location and suggesting appropriate solution. The research explores the relation between signal parameter values and Quality of Service parameters values under different circumstances and in different frequency bands, defining the dependency between the values of different parameters in LTE mobile networks. The statistical data used in the research has been gathered by making the practical measurements in the different geographical locations in different mobile electronic operators' networks, to ensure, that the results are applicable for different service providers networks, which have different policies and technical equipment. The approach for evaluating the dependency between different parameter values can be applied to practical on site measurements of the 5G networks for different mobile network operators.
In modern world, technology plays a significant role. Upcoming services, demanding a specific level of service quality that should be guaranteed no matter what, will impose obligations to network ...performance and capacity. European strategy for broadband development prescribes a set of quality indicators that networks should correspond. But imposed obligations themselves don't guarantee the persistent level of quality. European initiatives of geographical mapping of broadband access, which are developed in order to monitor the development of internet access services, propose guidance for gathering and representation of estimated QoS parameters at the so-called QoS-1 level, whereas monitoring of actual network performance on QoS-2 level and representation of real and objective internet quality indicators rests undefined. Besides ensuring that quality is described in meaningful and comparable manner the general measurement methodology that suits various purposes should be established. This research is aimed to develop principles of monitoring and objective representation of internet access service quality parameters in specific location on QoS-2 level, as well as to establish joint mechanism to obtain the quality of service data that would be appropriate for different needs. This research is directed to the mobile internet access service.
The 694–790 MHz band (700 MHz) known also as the second digital dividend was allocated to the mobile radiocommunication service on a primary basis in Region 1 and identified to International Mobile ...Telecommunications by the World Radiocommunication Conference 2012 (WRC-12). The designation of mobile service in Europe and other countries of Region 1 in 700 MHz band was obtained after the World Radiocommunication Conference 2015 (WRC-15). Administrations of Region 1 will be able to plan and use these frequencies for mobile networks, including IMT. The goal of this study is to estimate the electromagnetic compatibility of Digital Video Broadcasting – Terrestrial (DVB-T/DVB-T2) and LTE (Long Term Evolution) technology operating both in 700 MHz band. The study assumes frequency division duplex (FDD) channel arrangement of 703–733 MHz (for uplink) and of 758–788 MHz (for downlink).
The model contains two parts: a DVB-T/DVB-T2 system and LTE mobile broadband network. Co-channel scenario is considered in this paper, and possible impact of DVB-T/DVB-T2 on LTE base stations (receivers) is also investigated. The Monte Carlo simulations within SEAMCAT software and the Minimum Coupling Loss (MCL) method are used for interference investigation. The coordination trigger field strength value predetermined by GE06 Agreement is also used in this study. The Monte Carlo method presents more relaxed electromagnetic compatibility scenario in comparison with the MCL method. For SEAMCAT simulations, ITU-R P.1546-5 radio propagation model is used.
The obtained results present the required minimum separation distance between DVB-T/DVB-T2 and LTE networks in the 694–790 MHz in order to provide the necessary performance of LTE mobile network.
The paper demonstrates a spectrum slicing technique applied to PAM-4 modulated signal spectrum at 40 Gbaud baudrate for optical access networks. The spectrum slicing is shown in VPIphotonics ...simulation environment, where characteristics of key components are measured in the laboratory and loaded into the corresponding elements of the simulation setup. The spectrum of electrical baseband signal is sliced in four slices introducing an additional degree of freedom – higher data rate signals can be transmitted by re-using already-existing lower bandwidth transceiver components in an optical access network. This tackles the electronic bottleneck enabling the on-demand variable bandwidth allocation and extends the life span of opto-electrical components during network upgrades. Furthermore, the use of the proposed spectrum slicing technique has a positive side-effect when it comes to security concerns, as the signal spectrum is divided into slices. All slices are necessary to obtain the reconstructed signal and even if an eavesdropper gets most of the slices it is still not enough. The simulation results show that the proposed spectrum slicing and stitching approach is a viable solution to overcome the problem of limited frequency bandwidth of electrical components.
An optical fiber with a high Kerr nonlinearity coefficient has been proposed and manufactured from bismuth-modified tellurite glass for creation of non-classical multiphoton states of light. ...Specifically, we have proposed to use these fibers to squeeze the quantum fluctuations of one of the quadratures of light in the 20 W signal significantly below –10 dB compared to the standard quantum noise limit, which is important for various practical applications. Using numerical simulation based on the stochastic nonlinear Schrödinger equation, we have demonstrated noise squeezing stronger than –16 dB at tellurite fiber lengths of 6–14 m, while in squeezing of –14 dB is expected in silica glass fibers having lengths of 120–300 m. Analytical formulas were used to analyze the physical factors that limit the achievable squeezing.
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.
As the demand for fiber optical data transmission systems and other type of applications, which require optical media, like optical sensing increases, the unauthorized parties are becoming ...increasingly interested in such systems. Also, with such demand, more complex optical systems are required; thus, the network infrastructure is becoming more crowded. It is vital to economize on the available resources and infrastructure to ensure the needs of all interested business, governmental or end-user sides. Therefore, the present research focuses on the development of a unified hybrid optical system. The developed hybrid optical transmission system adds additional protection to the channels, allows for the unification of standard optical data transmission channels, optical sensors and spectrally hidden data transmission channel systems, and increases the efficiency of the optical components used.
Four-wave mixing optical frequency comb fibre-based setups (FWM-OFCs) have the potential to improve the combined dense wavelength division multiplexed passive optical network (DWDM-PON) and fibre ...Bragg grating (FBG) temperature sensors network providing easier application, broader technological opportunities for network development, and energy efficiency by substituting a power-demanding laser array.
In this research, OFCs are generated for the purpose of combined network application of DWDM-PON and FBG optical sensors. The paper also investigates compatibility scenarios with OFCs in such systems. The mathematical simulation model has been developed and the performance of FWM-OFC based 8-channel 50 GHz spaced non-return-to-zero on-off keying (NRZ-OOK) modulated DWDM-PON transmission system, operating at 50 km single-mode fibre (SMF) with a bit rate of at least 10 Gbps embedded with 7 FBG optical temperature sensors, has been studied. As it is shown, FWM application results in OFC source that has fluctuations of the individual comb tones of less than 3 dB in power, and with an extinction ratio of about 33 dB for operation range of 192.9–193.25 THz, acting as a unified light source for all the data transmission channels. Embedded FBG optical sensors network causes negligible 0.3 dB power penalty.
The paper presents the improved method of noise immune Fibonacci counting in the minimal form of representation. The method was tested and investigated in the developed noise immune pulse counter ...based on a minimal form of Fibonacci code with a fractal decoding device. The proposed device, which is simulated in the NI Multisim software, possesses a homogenous structure, increased noise immunity, performance and detection of bit errors in the process of its operation.
PDF
