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An experimental demonstration of direct-detection single-sideband Nyquist-pulse-shaped 16-QAM subcarrier modulated (Nyquist-SCM) transmission implementing a receiver-based signal-signal beat interference (SSBI) cancellation technique is described. The performance improvement with SSBI mitigation, which compensates for the nonlinear distortion caused by square-law detection, was quantified by simulations and experiments for a 7 × 25 Gb/s WDM Nyquist-SCM signal with a net optical information spectral density (ISD) of 2.0 (b/s)/Hz. A reduction of 3.6 dB in the back-to-back required OSNR at the HD-FEC threshold was achieved. The resulting reductions in BER in single channel and WDM transmission over distances of up to 800 km of uncompensated standard single-mode fiber (SSMF) achieved are presented.

A novel M-algorithm-based detection method called M-algorithm to maximum likelihood (M-ML) is proposed for spatial modulation. The proposed algorithm has fixed complexity and reduces complexity by using a parallel structure to limit the search space of an optimum decoder. The simulation results show that by carefully choosing proper values of M, the new algorithm can reduce the computational complexity significantly while maintaining a near-optimum bit error rate performance.Introduction: To meet the development of future mobile communication demands, the researches on wireless systems continue to strive for higher data rates. The multi-antenna technique is an important way to improve the channel capacity, but blindly pursuing excessively high rates will make multiple-input-multiple-output (MIMO) systems lose their edge in energy consumption and complexity reduction. To solve this problem, a single-radio-frequency large-scale MIMO technique called spatial modulation (SM) has emerged [1,2]. Compared with the conventional MIMO systems, SM has obvious advantages in transmission/reception complexity and energy efficiency, which make it a hot candidate technique for future wireless systems, especially the massive MIMO.In SM systems, the optimum detection method is the maximumlikelihood (ML) detection [3]. The complexity of the optimum receiver increases linearly with the number of transmit and receive antennas, and exponentially with the order of constellation. Therefore, the complexity of SM with large-scale antennas or high-order signalling constellation is still great, which motivates researchers to further reduce the complexity of the SM receiver. In [4-6], a novel detection algorithm for SM based on the modified sphere decoder (SM-SD) has been proposed. This algorithm applies the existing SD algorithm in MIMO systems to reduce complexity. However, like the conventional SD, the SM-SD has the same drawbacks, such as variable complexity and a serial detection structure, which make it difficult for practical applications [7]. However, there are many ways to reduce the complexity of ML detection in MIMO systems. A series of algorithms applying the M-algorithm to ML (M-ML) with fixed complexity and a breadth-first parallel structure are conducive to practical implementation [8].The M-ML algorithm combined with the limited tree search structure avoids exhaustive search by selecting only M candidates with the smallest accumulated metrics at each level of the tree. For achieving the near ML performance, M should be large enough for the selected points to include the correct one. The conventional M-algorithm in MIMO systems can be applied to SM by adding zero point to constellation without considering the characteristics of SM; however, the Euclidean distances between constellation points decrease so that the performance of the system degrades correspondingly.In this Letter, a modified M-ML method that considers the attributes of SM is proposed. Like the conventional M-ML, this algorithm with fixed complexity and a breadth...

Public landscape efficiency is one of the research hotspots in contemporary landscape performance. The renewal of micro landscape space has positive effects on community vitality and the sustainable development of landscape resources. The subway station entrance is a typical representative of the miniature landscape environment. To improve the construction of subway station entrances, clear cognition on the landscape efficiency of subway station entrances and their impact indicators is necessary. For this purpose, a structural equation model with a parameter system was established to measure landscape efficiency. There are four latent variables (e.g., traffic capacity) and 10 observed variables (e.g., visual level) composed of an estimation model. Researchers selected 131 subway station entrances in the main urban area of Nanjing as survey samples. Various methods, including investigation, image recognition, and modelling analysis, were comprehensively used to analyse the landscape characteristics of the subway station entrances quantitatively. A calculation was conducted to obtain the correlation coefficient of latent variables and the explanatory degree of observed variables. The result shows that green space landscapes and traffic capacity impresses the landscape efficiency of subway station entrances. Furthermore, all these variables have complex correlations. The fluctuation of any latent variable may cause the decay or enhancement of related variables. Therefore, designers should have a comprehensive cognition of the landscape environment of subway station entrances to enable them to propose balanced design strategies under traffic, visibility, plants and facilities. This paper aims to help designers gain an in-depth understanding of the ideal landscape construction forms at subway station entrances and facilitate the high-quality development of the urban landscape environment.

The magnetic resonance inductive coupling energy transfer from transmitter to receiver is designed in this project through magnetic inductive coupling. The transmitter sends energy through induction to the electrical devices from the transmitter to the receiver and then stores the energy in the batteries. Because the transmitter coil has a gap with the receiver coil. This wireless charging using two methods to show the output, first using the Taguchi Method and second using Superimposed Technique. The Result shows that output voltage must high than the input voltage and the same at secondary coil because using the same number of turns. The output voltage at the voltage regulator shows the output must in 5 Volts to charging the mobile phone with high efficiency.

With the application of engineering management in smart city construction under Industry 4.0, the intelligent design of urban street landscape has attracted extensive attention. Affected by the low intelligent level of traditional landscape design, the existing urban landscape composite system has difficulty in meeting the needs of smart city construction. Therefore, this paper proposes the construction of street landscape big data-driven intelligent decision support system based on Industry 4.0. Based on the complex network theory, this paper analyzes the structure, links, nodes, driving forces, and functional requirements of urban street landscape and then puts forward the construction content and implementation method of urban street landscape intelligent decision support system. The system consists of four aspects: intelligent infrastructure, service, protection and maintenance, and management and evaluation system. Its implementation not only reflects the cooperation and effective application of intelligent technology in each stage of street landscape construction, but also provides reference for the application of engineering management in other fields under Industry 4.0.

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International audienceThe exploding HD video streaming traffic calls for deploying content servers deeper inside network operators' infrastructures. Telco-CDN are new content distribution services that are managed by Internet Service Providers (ISP). Since the network operator controls both the infrastructure and the content delivery overlay, it is in a position to engineer telco-CDN so that networking resources are optimally utilized. In this paper, we show the following two findings: 1. it is possible to implement an efficient algorithm for the placement of video chunks into a telco-CDN. We present an algorithm, which is based on a genetic algorithm implemented on the MapReduce framework. We show that, for a national VoD service, computing a quasi- optimal placement is possible. 2. such push strategy makes sense because it allows to actually take into account fine-grain traffic management strategies on the underlying infrastructure. Our proposal re-opens the debate about the relevance of such "push" approach (where the manager of telco-CDN proactively pushes video content into servers) versus the traditional caching approach (where the content is pulled to the servers from requests of clients). Our proposal of a quasi-optimal tracker enables fair comparisons between both approaches for most traffic engineering policies. We illustrate the interest of our proposal in the context of a major European Telco-CDN with real traces from a popular Video-on-Demand (VoD) service. Our experimental results show that, given a perfect algorithm for predicting user preferences, our placement algorithm is able to keep aligned with LRU caching in terms of the traditional hit- ratio, but the workload on some troubled links (e.g., over-used links) in a push-based strategy is significantly alleviated