Wireless Personal Communications

Previously, a computer or mobile node was able to activate only one communication technology even though multiple heterogeneous technologies like Ethernet, WiFi, and 3G/4G available in the system. The above single communication technology use at a time may slow down the performance, if applications have higher bandwidth demand at a node. However, advent of Linux Kernel’s Bond driver tried to alleviate the above bottleneck by allowing use of multiple communication technologies’ interface at same time as required at node. Hence, the Linux bonding due to aggregation of multiple wired or wireless interfaces may support fault tolerance and throughput improvement. However, Linux bonding does not specifies, when to select which one or multiple interfaces with respect to one and multiple applications’ requirements as well as network condition at each interface of a node. In this paper we particularly addressed the above issue related to bonding the required number of heterogeneous interfaces depending upon applications an algorithm and various requirements at a user’s node. We have proposed and implemented it as a daemon in Linux Kernel that accomplishes bonding of only required number of radio interfaces both wired and wireless as active links with respect to bandwidth requirement. This daemon runs at user level of operating system and results reveal that scaling up/down of interfaces does not take significant time. For an example, average interface up delay observed 50ms by help of the daemon.

Using a global positioning system receiver in high dynamic condition needs to apply some method to help the receiver keep tracking lock on the signal as possible as can. Because of some benefits of the vector tracking method in comparison to the scalar method in GPS tracking loops for keeping lock on the signal, the vector tracking method is considered. To increase the tracking accuracy in high dynamic conditions, using some method of multiuser detection in the vector tracking loop is proposed. The variance analysis showed the improvement in performance of the proposed method.

Bean which is botanically called Phaseolus vulgaris L. belongs to the Fabaceae family. Unnecessary economic losses arise during bean disease identification due to a delay in treatment, inappropriate treatment, and a lack of understanding. The existing deep learning and machine learning techniques met few issues such as high computational complexity, higher cost associated with the training data, more execution time, noise, feature dimensionality, lower accuracy, low speed, etc. To tackle these problems, we have proposed a hybrid deep learning model with an Archimedes optimization algorithm (HDL-AOA) for bean disease classification. In this work, there are five bean classes of which one is a healthy class whereas the remaining four classes indicate different diseases such as Bean halo blight, Pythium diseases, Rhizoctonia root rot, and Anthracnose abnormalities acquired from the Soybean Data Set. The hybrid deep learning technique is the combination of wavelet packet decomposition (WPD) and long short-term memory (LSTM). Initially, the WPD decomposes the input images into four sub-series. For these sub-series, four LSTM networks were developed. During bean disease classification, an Archimedes optimization algorithm (AOA) enhances the classification accuracy for multiple single LSTM networks. To help the farmers in real-time, the proposed model is also deployed in a cloud-based collaboration framework. The proposed model accomplishes lower MAPE than other exiting methods. Finally, the proposed HDL-AOA model outperforms excellent classification results using different evaluation measures such as accuracy, specificity, sensitivity, precision, recall, and F-score.

With the rapid growth of the internet of things (IoT), an impressive number of IoT’s application based on wireless sensor networks (WSNs) has been deployed in various domain. Due to its wide ranged applications, WSNs that have the capability to monitor a given sensing field, became the most used platform of IoT. Therefore, coverage becomes one of the most important challenge of WSNs. The search for better positions to assign to the sensors in order to control each point of an area of interest and the collection of data from sensors are major concerns in WSNs. This work addresses these problems by providing a hybrid approach that ensures sensors deployment on a grid for targets coverage while taking into account connectivity. The proposed sequential hybrid approach is based on three algorithms. The first places the sensors so as to all targets are covered. The second removes redundancies from the placement algorithm to reduce the number of sensors deployed. The third one, based on the genetic algorithm, aims to generate a connected graph which provide a minimal path that links deployed sensors and sink. Simulations and a comparative study were carried out to prove the relevance of the proposed method.

The characteristics of high-spin, high-load and wide-range of the dual-spin trajectory correction projectile are the main design difficulties of the fixed canard rudder roll control system. Permanent magnet alternating generator within the limited space, which integrates the battery and rudder, as well as its driving and measuring system is designed based on the high-spin and dual-spin characters. Meanwhile, based on the analysis of structure and operating principle, the triple closed-loop roll control system based on parallel processors is proposed, and then the signals under strong interference are processed, completing the roll attitude solution within the whole scope of trajectory. A semi-physical simulation system is built to complete control experiments with the air torque respectively provided by torque motor and wind tunnel. The wireless transmission module has also been equipped to realize real-time display of the measured roll data on the terminal computer. The responding time is less than 0.7 s and the control precision is within ± 5°. It’s proved that the designed generator provides needful torque for control and also power supply for whole electrical circuits, saving both space and cost. It is also demonstrated that the proposed triple closed-loop roll control system has good feasibility, reliability and value in engineering application.

Present-day wireless methods are necessary to support a variety of higher-speed data communication facilities for its subscribers such as cloud-based video streaming facilities. One method to attain this is by using efficient resource allocation systems for transmitters and receivers using wireless communication methods. Wireless strategies and technologies are ubiquitous and enhancing progressively in the present world. In wireless communication technology, power and resource allocation remain the main issue due to the lack of resources by optimizing the number of subscribers and services. Hence, in this paper, we discuss different algorithms and techniques such as power-efficient resource allocation algorithm, real-time scheduling algorithm, NOMA, SCMA, Device-to-Device (D2D) communication, OFDMA, power and resource distribution in 5G, wireless sensor networks (WSNs), smart grids, cloud computing, and fog computing which converges stably and quickly. The Harmony search algorithm is also another way used for resources in wireless communication networks and discussed in this paper.

In this letter; we present a novel two-dimensional angle estimation for bistatic multiple-input multiple-output (MIMO) radar. We reconstruct the received signal of MIMO radar to model with quaternion theory, and then angle estimate using quaternion estimation of signal parameters via rotational invariance technique for MIMO radar is proposed. The proposed algorithm can obtain automatically paired two-dimensional angle estimation in MIMO-radar. The proposed algorithm has much better angle estimation performance than the Wang’s quaternion algorithm, which has a much heavier computational load than the proposed algorithm. Simulation results verify the usefulness of our algorithm.

Four-wave mixing effects mitigation techniques in wavelength division multiplexing systems which utilize hybrid configurations of dispersion compensating devices like dispersion compensating fiber, fiber bragg grating and optical phase conjugator are presented in this paper. These configurations have been simulated and the output results have been compared to find out the best alternative for four-wave mixing mitigation purpose. The comparison is carried out on the basis of parametric analysis and optimized parameter values. Optimization of important parameters has been done keeping a constraint on values of quality factor and minimum bit error rate values.

Trong bài báo này, chúng tôi mô tả ngắn gọn thiết kế, triển khai và đánh giá một phương pháp tối ưu hóa thích ứng mới cho phương pháp cân bằng định nghĩa bằng phần mềm theo hướng trước (FFSDE) sử dụng thuật toán phương pháp bình phương tối thiểu (LMS). Trong thiết kế của chúng tôi, chúng tôi thay đổi thích ứng độ dài bộ lọc (N) và kích thước bước ($$\mu$$) để đạt được giá trị tỷ lệ lỗi bit tối ưu. Chúng tôi đã sử dụng một máy phát tín hiệu vector RF PXI-5670 và một máy phân tích tín hiệu vector (VSA) RF PXI-5660 để kiểm tra tính hợp lệ của phương pháp của chúng tôi. Chúng tôi đã triển khai phương pháp của mình cho sơ đồ điều chế biên độ tứ phân M-ary (M-QAM) trong VSA (đóng vai trò là bộ thu). Kết quả thí nghiệm cho thấy chúng tôi đạt được tốc độ hội tụ cao và độ chính xác cho các đặc tính kênh phát thanh thay đổi nhanh. Tính năng thiết lập tối ưu tự động của các tham số thuật toán LMS N và $$\mu$$ đã cho phép chúng tôi giải quyết vấn đề cấu hình phần cứng cho phương pháp FFSDE. Việc xác định kích thước chuỗi huấn luyện của thuật toán LMS cho M-QAM cụ thể đã cho phép chúng tôi loại bỏ dữ liệu dư thừa của chuỗi huấn luyện và tăng cường khả năng thông qua.

Quality of Service is particularly necessary to serve delay-sensitive applications in heavy-loaded wireless networks. In this paper we evaluate a strategy of combining packet dropping and scheduling policies at Medium Access Control layer in guaranteeing maximum packet latency for real-time applications. The purpose of this work is to evaluate how significance the mentioned combination schemes can meet the required latency and also the achievable system throughput. For the case study, a real time Polling Service class in the Worldwide Interoperability for Microwave Access System for downlink transmission is assumed. The main analysis is undertaken for User Datagram Protocol (UDP) traffic in stationary and mobile user scenarios under heavy load conditions, and the impact of mixed Transmission Control Protocol and UDP traffic is also investigated. Results show that the introduction of a packet dropping policy ensures that the latency is kept well within the required maximum latency requirement, regardless of the types of scheduler used. However, the packet drop percentage (or packet loss) depends strongly on the types of schedulers. All schedulers show similar goodput performance for low load conditions, and the results can only be distinguished for the cases of heavy load/overloaded conditions.