Performance Evaluation Of Transmission Research Articles

Experimental performance evaluation of analog signal transmission in a silicon microring resonator.

We experimentally evaluate the performance of analog signal transmission in a silicon microring resonator. The spurious free dynamic range (SFDR) of the second-order harmonic distortion (SHD) and third-order harmonic distortion (THD) is used to assess the analog link. The performance dependence on the input signal wavelength and input signal power is comprehensively studied. The obtained results indicate that the analog signal transmission performance through microring resonator is mainly affected by the notch filtering effect for low-level input signal power. Moreover, with the increase of input signal power, the enhanced nonlinear resonance in the microring resonator could cause the shift of the resonance wavelength, which might also impact on the analog signal transmission performance.

Performance evaluation of analog signal transmission in an orbital angular momentum multiplexing system.

We propose and experimentally demonstrate analog signal transmission in an orbital angular momentum (OAM) multiplexing system. By employing two spatial light modulators (SLMs), each loaded with a complex phase pattern generating 4OAM beams, an 8OAM multiplexing system is established for analog signal transmissions. The crosstalk between each OAM channel is measured to assess the performance of the OAM multiplexing system. Using 3-GHz analog signals over 8OAM beams, we evaluate the performance of OAM multiplexing analog signal transmissions. The spurious free dynamic range (SFDR) of the second-order-harmonic distortion (SHD) and the third-order-harmonic distortion (THD) are measured and characterized for each OAM channel.

FBG光ファイバセンシングによる回転軸の光学的空間伝送性能評価

FBG光ファイバセンシングによる回転軸の光学的空間伝送性能評価

Performance evaluation of transmission of electricity in the sip–lines in electric distribution networks

A method of performance evaluation of electricity transmission through modern electricity transmission SIP-lines of electric distribution networks in conditions of abruptly variable, nonlinear and asymmetric operation mode of electricity consumers was proposed in the paper. The specified operation mode of consumers meet modern operation conditions of the electrical network and is almost not considered in existing calculation methods of the actual electricity losses in the network that does not allow to adequately assess real energy efficiency of electric networks. The proposed evaluation method of electricity losses is based on measuring the current THD and values of harmonic components of currents and voltages in the network that allows to use existing measuring instruments - electricity quality analyzers for evaluation. The relationship between the measured electricity quality parameters and the instantaneous voltage change rate allows to estimate the share of electricity losses, which is caused by abruptly variable, nonlinear and asymmetric operation mode of consumers. Application of the developed method allows to assess the level of additional electricity losses in order to analyze the causes of the deterioration of electricity transmission efficiency, reduce these losses and increase energy efficiency of electricity transmission through the network. It was shown that in the modern electric distribution networks, additional electricity losses are almost 10% due to the presence of higher harmonic components of currents and voltages in the electric network.

Evaluation of optical ZP-OFDM transmission performance in multimode fiber links

In this paper, the performance of Zero Padding Orthogonal Frequency Division Multiplexing (ZP-OFDM) on intensity modulation-direct detection (IM-DD) multimode fiber (MMF) links is assessed by means of numerical simulations. The performance of ZP-OFDM is compared to classical Cyclic Prefixed form of OFDM (CP-OFDM) which is known to offer a limited performance in terms of symbol recovery in subcarriers suffering severe fading. Simulations results show that ZP-OFDM is able to reach 29 Gbps in 99.5% of all installed MMF links up to 600 meters compared to 14 Gbps for CP-OFDM when a 64 points fast Fourier transform (FFT) size is used. The use of ZP-OFDM makes it possible to increase the link length up to 1200 and 2400 m with a 25 Gbps data rate if the FFT sizes are increased to 128 and 256 points, respectively; whereas the CP-OFDM scheme will offer a maximum data rate of 10 Gbps in both cases. ZP-OFDM can be an alternative to adaptive loading OFDM schemes without the need of a negotiation between transmitter and receiver, reducing the system deployment complexity and increasing the flexibility in scenarios with multiple receivers.

Transmission behavior improvement of electro‐optic modulators for integrated photonic systems in the present communication technology

SummaryThis paper has presented the transmission performance evaluation of different electro‐optic modulators (EOM) for ultra high switching speed operations and applications. As well as the optimization design parameters for different EOMs have been investigated, where the effective refractive index plays an essential role in the evaluation of the bandwidth structure. The effects of the operating parameters on the switching, modulating voltage, device performance index, and optical bandwidth are also investigated for different material‐based EOMs, where the transmission bit rate is evaluated by using non‐return‐to‐zero coding transmission technique. As well as lithium niobate, gallium arsenide, and poly methyl metha acrylate polymer EOMs have been developed for extensive use in high speed and high transmission performance optical fiber transmission systems. Copyright © 2013 John Wiley & Sons, Ltd.

Kinematics Performance Analysis of a Robot Hip Joint

Kinematics research of mechanism is very important, the dynamic analysis and the design are based on linematics analysis. In this paper, a novel robot hip joint based on 3-RRR orthogonal spherical parallel mechanism is proposed, and Jacobin matrix is established. Then the linematics transmission performance evaluation index is defined. Furthermore the linematics transmission performance index is analyzed. The hip joint has good linematics transmission performance at the initial position. With the increase of workspace, linematics transmission performance gradually decreased. 3-RRR parallel mechanism is the ideal prototype of bionic robot and rehabilitation robot hip joint.

Statistical performance evaluation of ECG transmission using wireless networks

This paper presents simulation of the transmission of biomedical signals (using ECG signal as an example) over wireless networks. Investigation of the effect of channel impairments including SNR, pathloss exponent, path delay and network impairments such as packet loss probability; on the diagnosability of the received ECG signal are presented. The ECG signal is transmitted through a wireless network system composed of two communication protocols; an 802.15.4- ZigBee protocol and an 802.11b protocol. The performance of the transmission is evaluated using higher order statistics parameters such as kurtosis and Negative Entropy in addition to the common techniques such as the PRD, RMS and Cross Correlation.

Performance signature and optical signal processing of high speed electro-optic modulators

This paper has presented the transmission performance evaluation of polymer and semiconductor elect-optic modulators for ultra high speed operations and applications. The modulated bandwidth, the transmitted signal bandwidth, and data transmission rates within modified Shannon technique are deeply and parametrically designed over wide ranges of the affecting set of parameters via specially designed software which processes the interaction of causes and effects. The design parameters of the lumped circuit have been processed over large operating requirements. As the bit rates of optical network systems become high, it becomes more difficult to drive a modulator with a high voltage. Therefore, reduction of the driving voltage of electro optic modulator (EOM) with a broadband characteristic is an extremely important issue for realizing future high speed optical transmission systems. Moreover polymer electro-optic devices have been extensively studied and explored due to its intrinsic advantages over conventional materials such as high speed operation, compatibility with other materials and substrates.

Performance Evaluation of Data Transmission in Maritime Delay-Tolerant-Networks

Performance Evaluation of Data Transmission in Maritime Delay-Tolerant-Networks

Modulation Schemes of SDR for RFID Signal Transmission Performance Evaluation

This paper presents a performance evaluation of a radio frequency identification (RFID) signal-transmission framework in software-defined radio (SDR) using phase shift keying and quadrature amplitude modulation schemes. The RFID signals were compared within the SDR framework with respect to SDR performance. The SDR system performance was evaluated by analyzing signal transmission, estimating bit-error rate and comparing signal-to-noise ratios (SNR), with satisfactory results. The eye diagrams were also computed and compared with the SNR to evaluate the SDR signal-transmission performance.

Evaluation of Transmission Performance of MIMO Multiplexing in 42-GHz Band by using Orthogonal Polarization in Line-of-Sight Environment

Evaluation of Transmission Performance of MIMO Multiplexing in 42-GHz Band by using Orthogonal Polarization in Line-of-Sight Environment

Performance Evaluation of Secure Video Transmission over WIMAX

WiMAX is a wireless digital communication system based on the IEEE 802.16 standard which provides broadband wireless Internet access at very high rates that is up to 70 Mbps or a data rate of about 3 Mbps within a radius of 30-mile (data rate increases as the distance decreases). With the rapid increase in the wireless broadband use, the need for wireless fixed and mobile metropolitan area networks has ever been increasing. Multimedia communications, including audio and video are highly bandwidth demanding and error sensitive. When the coverage area of the wireless network technology is as high as with WiMAX, security becomes one of the most important issues.WiMAX, both mobile and fixed, has many attractive features such as connection-oriented MAC layer, provision of the Quality-of-Service (QoS) for different applications, efficient mobility and power save mode features. Needless to say, all these attractive features must be protected against malicious activities by security mechanisms.Providing secure multimedia communications by using a broadband wireless technology like WiMAXis likely to be challenging due to time or space overhead that occur. Security mechanisms might increase packet sizes thus delay, jitter and throughput are increased. In this paper, we evaluate the performance of secure video transmission over WiMAX networks under different cryptographic algorithms by using the OPNET simulator. The outcome of the results show negligible overhead introduced by the security extensions giving credence to their application in security sensitive scenarios.

Successful Transmission Rate of Mobile Terminals with Agents in Segmented Ad Hoc Network

Mobile Wireless Ad-Hoc Network (MANET) is a special kind of network, where all of the nodes move in time. Random movement is the commonly used to model the mobility in this network. Beside as a host, each node is intended to help relaying packets of neighboring nodes using multi-hop routing mechanism in order to solve problem of dead communication. In recent years, a variety of routing protocols have been proposed specially to accommodate this environment followed with its performance evaluations, likes DSDV, DSR, AODV, and extension OSPF. Researches in this network are mostly simulation based. Research efforts haven't focused much in evaluating network performance when applied to variable number of nodes that involving agents and distributed over several network areas. The paper performed simulations using MANET simulator, which carried out based on the extension OSPF routing protocol. The modification of OSPF protocol had intended to suit the OSPF standard mechanisms for operating with high performance over wireless networks characterized by a broadcast-based transmission medium, in which the physical layer connectivity is not fully meshed. Extensive simulation scenarios have been conducted in the simulator with various numbers of nodes, random and uniform movement direction, and different agent’s quantity with different size of network areas. In the performance evaluation of successful transmission (data) packets, the OSPF protocol with throughput weighted metric will be tested under different combination conditions of scenarios.

Performance evaluation of UWB signal transmission over optical fiber

UWB over fiber (UWBoF) technique has been proposed to increase the area of coverage for UWB communication systems. In this paper, the transmission performance of impulse UWB signals over optical fiber is analyzed. Three types of UWB signals generated based on three different techniques are considered. Since optical signals with different optical spectra would have different tolerances to fiber dispersion, the transmission performance of the three types of UWB signals is studied. First, the impact of fiber chromatic dispersion on UWB waveforms and their spectra is evaluated. Then, the transmission performance of data-modulated UWB signals in an optical fiber is investigated, with a general model to analyze the signal power spectral density (PSD) being developed. The PSD of an UWB signal with on-off keying (OOK), bi-phase modulation (BPM) and pulse position modulation (PPM) schemes is calculated. Evolution of the PSD as a function of transmission distance is then performed. The suitability of the three types of UWB signals for UWBoF applications is also evaluated. The study provides a guideline for the design and development of a practical UWBoF system.

Performance evaluation of split transmission in multihop wireless networks

Multimedia applications in multihop wireless networks have great market potential. Multiple channels and multiple radios are commonly used for exploring multimedia transmissions in multihop wireless networks. Split transmission allows multiple channels attached to different radios simultaneously to be used, and so to achieve a fundamentally improved transmission capacity. The goal of this paper is to present a theoretical background to justify the improved performance of the split transmission. We theoretically study and prove that, by using the split transmission, the worst-case delay is decreased to $\frac{\sigma\rho_{k-1}}{LC_{m-1}C_{k-1}}$ of that without using the split transmission, the average throughput is increased to $\frac{1}{1-\prod_{j=0}^{k-1}\alpha_j}$ of that without using the split transmission, and the average delay jitter is decreased to $\frac{C_{k-1}C_{\rho}}{C_{m-1}[C_{\rho}+L(\rho+C)]}$ of that without using the split transmission. We believe that this is the first attempt to consider split transmission in theory. We also evaluate the performance of the split transmission in ns-2 simulations. The observed results show that the split transmission achieves shorter worst packet delays, higher average throughput, and smaller average delay jitter as compared to the performance achieved without the split transmission.

Performance evaluation of multiband orthogonal frequency division multiplexing ultra-wideband signal transmission over multimode fibre

The performance of multiband orthogonal frequency division multiplexing ultra-wideband (UWB) signal over a multimode fibre-based radio-over-fibre link is discussed. The co-transmissions of UWB signals with other wireless signal standards, including wireless code division multiple access (W-CDMA) (2.15 GHz), wireless local area network 802.11a/g and global system for mobile communication (1.8 GHz) are considered. Based on the measurement results, it has been shown that UWB signals can be transmitted without error over 400 m for the highest data rate of 480 Mbps using the system proposed. The co-transmission can also be successfully done with minimal mutual interference.

An analytical approach for performance evaluation of BICM transmission over Nakagami-m fading channels

Bit-interleaved coded modulation (BICM) has established itself as a quasi-standard for bandwidth- and power-efficient wireless communication. In this paper, we present an analytical approach to evaluate the performance of BICM transmission over frequency-flat fading additive white Gaussian noise channels. The statistic of the fading envelope is modeled as Nakagami-m distributed, which spans a wide range of practical multipath fading scenarios through adjustment of the m-parameter. For this setup, we derive approximations for the bit-error rate (BER) and cutoff rate of BICM. Different from previously proposed methods, our analysis is valid for general quadrature amplitude modulation and phase shift keying signal constellations and arbitrary bit-to-symbol mapping rules, and it results in simple closed-form expressions. The key idea is to use well-chosen subsets of signal points to approximate the probability density function of reliability metrics used for decoding. This approximation is accurate for signal-to-noise ratio regions of interest for BICM systems with moderate coding complexity such as, e.g., convolutional coded BICM systems. Based on this approximation we also derive an asymptotic BER expression, which reveals the diversity order and coding gain of BICM. The usefulness of the proposed analytical approach is validated through numerical and simulation results for a number of BICM transmission examples.

Study on Transmission Mechanism and Transmission Performance Evaluation of Steel Worm Gear Pair with New Coatings

In order to solve the problems of poor wear resistance and low fatigue strength of bronze worm wheel,new functional coating on the steel worm wheel is investigated.After the elastic contact analysis,tooth wear and bulk temperature on the worm gearing,the relational model between the material properties and stress,wear ratio and temperature on the tooth is established.A method is presented to evaluate the meshing performance,wear resistance,and anti-scuffing of worm gearing.Superfine manganese phosphate conversion coating and ferrous sulfide solid lubricant coating are formed on the surface of 20Cr steel by means of new processes.The tribological properties of the coatings are investigated on a friction and wear test machine.The steel worm gearings with the two coatings are tested on the transmission test-bed.The experimental results show that the steel worm gear with the coatings can reduce the running-in time,and improve the transmission efficiency and anti-scuffing capacity.The approach is very useful to the substituion of steel worm gearing for bronze worm gearing.

Research on the Performance of Protocols and the Evaluation Metric for VIDEO Transmissions in an Ad Hoc Network

Video transmission effectiveness in the Ad Hoc network is becoming important recently, if different routing protocols are applied. Some researchers conclude that the reactive protocols are better for file transfer protocol (FTP) and constant bit rate (CBR) or hypertext transfer protocol (HTTP) transmission in an Ad Hoc wireless network but the performance report of video transmission is not much. This study adopts Qualnet (Network Simulator) as a simulation tool for environmental designing and performance testing, and employs an experimental design with eight groups. Our experiment shows that: (1) The performance of AODV (reactive) protocol is better than DSDV, ZRP and DSR when the transmission load has only one video stream; (2) Proactive (DSDV) and Hybrid protocols (ZRP) are better for a smaller Ad Hoc network when it transmits a video stream with some applications (VoIP, FTP and CBR). We conclude that packet loss rate is sensitive to the quality of video transmission and it has negative relationship with Peak Signal‐to‐Noise Ratio (PSNR) value. In addition, our experiment also shows that PSNR is a simple Metric for the performance evaluation of video transmission.