Figure - available from: Photonic Network Communications
This content is subject to copyright. Terms and conditions apply.
Source publication
Due to the fast development of telecommunications and the great demand of bandwidth, optical wireless communication (OWC) has become a promising trend. OWC offers flexible networks for both indoor and outdoor communications providing high security, high speed and a license free spectrum. Data transmission over indoor OWC systems with diffused chann...
Similar publications
Orthogonal Frequency Division Multiplexing (OFDM) is a well-known technique used in modern wide band wireless communication systems. Coherent OFDM systems achieve its advantages over a multipath fading channel, if channel impulse response is estimated precisely at the receiver. Pilot-aided channel estimation in wide band OFDM systems adopts the rec...
This work proposes a new angle of arrival method for tracking applications using compact Omni-directional spiral antenna arrays. The impact of mutual coupling is considered within the covariance matrix calculation and then a suitable decoupling method is used to remove such effect. An urban area consisting of many buildings with different heights a...
Citations
... ACO-OFDM and DCO-OFDM techniques are considered as strong options for MIMO-VLC systems. However, some studies have been carried out in the literature to resolve the DC bias addition disadvantage of DCO-OFDM and to obtain a higher band efficiency than ACO-OFDM [11][12][13][14][15]. NDC-O-OFDM has been proposed as a unique MIMO-VLC system that overcomes the disadvantages of ACO-OFDM and DCO-OFDM [9,10]. ...
... On the other hand, it is determined that the best performances are obtained with 060 and 070 channels given in Eqs. (13) and (14). The next comparisons will be made over the 060 channel. ...
In recent years, the lifting wavelet transform (LWT) has been used in image and signal processing applications to overcome many of the shortcomings of the classical discrete wavelet transform (DWT). The LWT is a simplified and most efficient version of the classical discrete wavelet transform. To address the issue of energy inefficiency in the direct current-biased optical OFDM (DCO-OFDM) waveform, the literature proposes the use of the non-direct current-biased optical OFDM (NDC-O-OFDM) waveform, which does not require the addition of DC bias. Firstly, this paper proposes improving the performance of the NDC-O-OFDM waveform by combining it with the LWT using the lazy wavelet (LLWT). However, the literature proposes the use of the generalized LED index modulation OFDM (GLIM-OFDM) waveform as a solution to the spectrum inefficiency problem of the NDC-O-OFDM waveform. As a second contribution, this paper presents the combination of the GLIM-OFDM waveform with the LLWT transform to enhance the performance of the GLIM-OFDM waveform. Numerical simulations were performed to evaluate the performance of the proposed LLWT-NDC-O-OFDM and LLWT-GLIM-OFDM waveforms in terms of bit error rate (BER) in 2 × 2 and 4 × 4 optical MIMO channel environments. The results show that the proposed waveforms provide a gain of approximately 6.5 dB over both the NDC-O-OFDM and GLIM-OFDM waveforms, and a gain of 13.5 dB over the DCO-OFDM waveform, while maintaining the same BER requirement of 1E-4 and modulation order of BPSK in both 2 × 2 and 4 × 4 optical MIMO channel scenarios. Thus, despite some increase in computational complexity due to LWT implementation, a spectrum and energy efficient high performance optical OFDM waveform is achieved with the proposed LLWT transform in this work.
... where y is the received time-domain signal, x OOFDM is the transmitted time-domain signal, and g is the total channel gain, which can be described as g = ηRh; η is the electrical-tooptical efficiency of the LED. R is the responsivity of the photodetector (PD), and h is the optical channel gain, which is expressed as follows [53]: ...
Visible Light Communication (VLC) systems are favoured for numerous applications due to their extensive bandwidth and resilience to electromagnetic interference. This study delineates various constructions of Optical Orthogonal Frequency Division Multiplexing (O-OFDM) approaches employed in VLC systems. Various factors are elaborated within this context to ascertain a more effective O-OFDM approach, including constellation size, data arrangement and spectral efficiency, power efficiency, computational complexity, bit error rate (BER), and peak-to-average power ratio (PAPR). This paper seeks to assess these approaches' BER and PAPR performance across varying modulation orders. Regrettably, in VLC systems based on OFDM methodology, the superposition of multiple subcarriers results in a high PAPR. Therefore, this study aims to diminish the PAPR in VLC systems, enhancing system performance. We propose a non-distorting PAPR reduction technique, namely the Vandermonde-Like Matrix (VLM) precoding technique. The suggested technique is implemented across various O-OFDM approaches, including DCO-OFDM, ADO-OFDM, ACO-OFDM, FLIP-OFDM, ASCO-OFDM, and LACO-OFDM. Notably, this method does not affect the system's data rate because it does not require the mandatory transmission of side information. Furthermore, this technique can decrease the PAPR without impacting the system's BER performance. This study compares the proposed PAPR reduction technique against established methods documented in the literature to evaluate their efficacy and validity rigorously.
... QAM demodulation, a technique using the same modulation scheme for optical fiber, is often used and known as coherent detection. By using these fancy methods, we can send data quicker, use the spectrum more efficiently, and hold up better against noise and interference [25][26][27][28][29][30]. ...
This work aims to clarify an average data rates transmission through the lighted multi paths network with/ without converted wavelength. The user bit rate transmission distribution at downstream/upstream directions is studied against links number per fiber with 90% channel utilization for both EPON and GPON light networks. The possible data rates transmission in the downstream direction is clarified versus supported users number with 90% channel utilization for both EPON and GPON light networks. The user bit rate transmission distribution is demonstrated at downstream/ upstream direction against links number per fiber with 90% channel utilization for both GPON/EPON light networks. The estimated total traffic load is clarified with high data rates transmission through the lighted passive multi paths networks, Throughput through single path or multi paths for various network algorithms are demonstrated. Also the throughput through single path or multi paths for non wavelength conversion is studied based on various network operation algorithms such as fast forward (FF), random, lower/upper (LU), and medium/upper (MU). The proposed 1 3 algorithms are employed for the optimized case of estimated traffic load. The traffic load can be optimized through the employment of wavelength conversion especially through the single path network. The estimated traffic load is higher in multi path network in compared to single path network.
... Photonic crystal fiber (PCF) enhanced sensors are important because it's highly sensitive, micro structured, adaptive, and physically robust [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. From a PCF, properties for example relative sensitivity, effective area, numerical aperture, etc. can be determined to enhance geometrical form and arrangement of air holes, core and cladding airholes radius both are used and the space between two neighboring air holes that is called pitch which are hard to gain in typical optical fibers [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. ...
High stability with low polarization and confinement loss based new structure of photonic crystal fiber waveguide profile Abstract: Nowadays ethanol is broadly used chemical item in various industrial purpose. So, detection of this organic chemical has become very important task in industrial basis. In this paper, a hexagonal core PCF has constructed in which silica is used as base material. A finite element method is applied and mesh analysis has been done for investigating boundary conditions of proposed PCF sensor. After simulation , 59.48 % sensitivity and an ignorable loss of confinement which is 8·956020 × 10 −13 cm −1 at 2.5 THz frequency has been gained. Focusing on easy construction of fiber, conventional fabrication procedures are attainable. Having satisfactory waveguiding attributes, the proposed sensor can be applicable effectively for sensing ethanol and also polarization-based applications of terahertz waves.
... There are many types of actuation such as the electrostatic, thermal, and piezoelectric [1][2][3][4][5][6][7][8][9][10][11][12][13]. The electrostatic actuation is classified into the normal motion, torsional motion, and lateral motion [14][15][16][17][18][19][20][21][22][23][24][25][26]. ...
This study has clarified the performance evaluation simulation of the optical splitters integrated with unidirectional fiber elements. The simulative performance evaluation of electrostatic, thermal, and piezoelectric actu-ation based micro electro mechanical systems. The force against the displacement based electrostatic and elastic forces for parallel plate actuator is simulated by MEMSover simulation software. The voltage with angular displacement for a torsion bar actuator is clarified. Besides the lateral displacement against voltage for a comb drive actuator is reported. The dependence of the film thickness on the deflection of a bimetallic cantilever, the dependence of passive beam length on deflection of a bimorph actuator and the transient response of a bent beam actuator are demonstrated. Moreover the piezoelectric actuator force against applied voltage and the piezoelectric actuator displacement against applied voltage variations are reported.
... Multiplexing techniques is used to send high data rate of media from TX to RX. With low cost and no time [1][2][3][4][5][6][7][8][9][10][11][12][13]. A high-speed channel is created by multiplexing low-rate signals into one channel for transmission [14][15][16][17][18][19][20][21][22][23][24][25], followed by demultiplexing or reconstruction at the receiving end [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. ...
This work demonstrates the optical duobinary transmitter based optical quadature phase shift keying line coding phase offset for the prediction of optical fiber wireless channel systems performance efficiency. The max signal light power variations with the spectral wavelength variations for different degree phase offsets based optical quadrature phase shift keying (OQPSK) transmitter are clarified. The max signal light power variations with the time variations for various degrees phase offset based OQPSK transmitter are demonstrated. The total power lighted after OWC channel for various degree phase offset based OQPSK transmitter are indicated. The max electrical power signal amplitude variations with the time variations for various degree phase offset based OQPSK transmitter are observed. Total electrical power signal after optical receiver for various degree phase offset based OQPSK transmitter is clarified. Total optical power variations after OWC channel for various degrees phase offset based OQPSK transmitter is studied.
... In order to address the expanding need for Band width development, ultra high multiplexing networks with a variety of lighted base band sources are being deployed, leads to the increase in dense and pricey deployment. Furthermore, a traditional single-mode FO is physically unable to support more data than 100 Tbit/s [1][2][3][4][5][6][7][8][9][10][11][12][13]. To improve broadcast BW even more, fresh ideas must be developed [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. ...
This study has demonstrated the efficient employment of optical DPSK transmitter with linear multimode fibers and FSO channel under various duty cycle coding effects. The light signal power form variations after linear multimode fiber versus spectral wavelength based various RZ-percentage duty cycle coding is clarified. The light signal power form variations after linear multimode fiber versus spectral wavelength based various NRZ duty cycle coding is also clarified. The light power signal form variations after FSO channel versus spectral wavelength based different RZ percentage duty cycle coding is analyzed. Moreover the light power signal form variations after FSO channel versus spectral wavelength based NRZ percentage duty cycle coding is investigated. The light signal power form variations after linear multimode fiber versus spectral wavelength based various RZ percentage duty cycle coding and NRZ modulation code are indicated.
... The preamble may also include a distinct waveform to aid in synchronization because each base band slot should be selfsynchronizing (each receiver must be able to establish symbol synchronization) [1][2][3][4][5][6][7][8][9][10][11][12]. In certain systems, error control information is also included in the preamble (e.g., parity bits) [13][14][15][16][17][18][19][20][21][22][23][24][25][26]. ...
This work has been clarified the optical differential phase shift keying transceiver systems performance efficiency at high data rate optical systems in the presence of pr doped amplifiers. The Max optical signal power variations after fiber link versus wavelength variations at various system data rates are demonstrated. The total optical power within optical fiber at data rates from 10 to 100 Gbps are indicated. The Max electrical signal power variations against frequency after receiver variations at various system data rates are clarified. The total electrical power after receiver at various system data rates are demonstrated. The light/elec-trical power received, OSNR and SNR variations in relation to data rate variations are also studied.
... Sub carrier code multiplexing is a technique used to increase the BW of optical networks. The SCM method combines a variety of electrical signals with various frequencies to communicate via a single optical light [1][2][3][4][5][6][7][8][9][10][11][12]. The polarizations angle of each data channel is unique [13][14][15][16][17][18][19][20][21][22][23][24][25]. ...
This study has clarified various RZ Percentage Duty Cycle Coding with NRZ modulation Technique Signature on The Fiber System Performance. The total form lighted/electrical power after linear measured multimode fiber/FSO channel measured based different RZ percentage duty cycle coding with the assistance of NRZ modulation techniques is performed. The electrical/lighted form measured power after APD receiver with linear multimode fiber/FSO channel measured based different RZ percentage base band form duty cycle coding with the assistance of NRZ modulation techniques is demonstrated. The lighted based band form can be used for the modulation of the based band electrical signal form based on the RZ percentage duty cycle coding with the assistance of NRZ for both linear measured multimode fiber and FSO measured channel.
... As the silicon mechanical structures with the basic beams and the basic diaphragms are the most basic important parts for micro electrical mechanical system (MEMS) devices, the beam mechanics and diaphragm structures will be reviewed in many researches according to the elasticity theory for the homogeneous material [1][2][3][4][5][6][7][8][9][10][11][12]. There are many types of diaphragms [13][14][15][16][17][18][19][20][21][22][23][24][25][26]. ...
Performance evaluation of various distributors and exchange elements configurations in the optical fiber communication system under optimum operating conditions Abstract: This study reported the performance evaluation of various distributors and exchange elements configurations in the optical fiber communication system. The study of different diaphragm structures mechanics under different pressure levels effects. The stress along the x axis of a square diaphragm and the deflection of a square diaphragm under pressure are reported. The radial and tangential stress of a round diaphragm and the deflection of a round diaphragm under pressure are outlined. 3D for the bossed diaphragm deflection against diaphragm position is clarified. The stress distribution across the shorter side of a rectangular diaphragm and 3D for the rectangular diaphragm deflection against diaphragm position under pressure are demonstrated. The radial stress is larger than the tangential stress through the diaphragm radial position from 50 μm to 250 μm for a square diaphragm under pressure. The radial stress is larger than the tangential stress for the bossed diaphragm position varies from 125 μm to 250 μm. All the obtained results are demonstrated through the use of the MEMSolver simulation program software version 3.3.
