Terahertz Wireless Communications

With Wireless communications in the 0.1-10TeraHertz(THz)band are envisioned as one of the key enablers towards ubiquitous wireless communications beyond 5G accommodating a massive number of connected devices and ultra-high user data rates in the order of Tera-bit-per-second.The THz band is located between the millimeter-wave(mmWave)and the far infrared(IR)band and still considered as one of the least investigated and exploited regions in the electromagnetic spectrum.

Image Classification with Superpixels and Feature Fusion Method

This paper presents an effective image classification algorithm based on superpixels and feature fusion.Differing from classical image classification algorithms that extract feature descriptors directly from the original image,the proposed method first segments the input image into superpixels and,then,several different types of features are calculated according to these superpixels.To increase classification accuracy,the dimensions of these features are reduced using the principal component analysis(PCA)algorithm followed by a weighted serial feature fusion strategy.After constructing a coding dictionary using the nonnegative matrix factorization(NMF)algorithm,the input image is recognized by a support vector machine(SVM)model.The effectiveness of the proposed method was tested on the public Scene-15,Caltech-101,and Caltech-256 datasets,and the experimental results demonstrate that the proposed method can effectively improve image classification accuracy.

MOBILE INETERNET

As most terminals sold today offer wireless Internet connectivity as a primary feature for personal communication requirements, the "Mobile Internet" is rapidly flourishing in the information society. And, yet,

Special Topic on Federated Learning over Wireless Networks

Federated learning has revolutionized the way we approach machine learning by enabling multiple edge devices to collaboratively learn a shared machine learning model without the need for centralized data collection.Such a new machine learning paradigm has gained significant attention in recent years due to its ability to address privacy and security concerns associated with centralized learning,as well as its potential to reduce communication overhead and improve scalability.

A Double Sensitive Fault Detection Filter for Positive Markovian Jump Systems With A Hybrid Event-Triggered Mechanism

This paper is concerned with the double sensitive fault detection filter for positive Markovian jump systems. A new hybrid adaptive event-triggered mechanism is proposed by introducing a non-monotonic adaptive law. A linear adaptive event-triggered threshold is established by virtue of 1-norm inequality.Under such a triggering strategy, the original system can be transformed into an interval uncertain system. By using a stochastic copositive Lyapunov function, an asynchronous fault detection filter is designed for positive Markovian jump systems(PMJSs) in terms of linear programming. The presented filter satisfies both L_-gain(?_-gain) fault sensitivity and L_1(?_1)internal differential privacy sensitivity. The proposed approach is also extended to the discrete-time case. Finally, two examples are provided to illustrate the effectiveness of the proposed design.

Aerial RIS-aided physical layer security design for satellitecommunication among similar channels

Satellite communications and reconfigurable intelligent surface (RIS) are considered as twopromising technologies that can significantly improve the coverage and energy efficiency of futurewireless communication networks. The satellite communications security is often threatened dueto its broadcasting nature. To enhance the physical layer security (PLS) of satellite communications with channel similarity, an aerial RIS-aided dual full-duplex (DFD-ARIS) cooperative jamming method is presented in this paper. Specifically, unlike the existing works that relied onchannel difference, DFD-ARIS utilizes the channel similarity against the eavesdroppers with thehelp of ARIS. In addition, the power allocation is further studied in conjunction with the phasedesign of RIS to minimize the total power under the constraints of data rate, satellite powerlimitation and secrecy rate. Then, the closed-form solutions are achieved. Simulation results showthat the performance of the proposed scheme is superior to the traditional method.

Mobile-Edge Computing Framework with Data Compression for Wireless Network in Energy Internet

Under the situations of energy dilemma, energy Internet has become one of the most important technologies in international academic and industrial areas. However, massive small data from users, which are too scattered and unsuitable for compression, can easily exhaust computational resources and lower random access possibility, thereby reducing system performance. Moreover, electric substations are sensitive to transmission latency of user data, such as controlling information. However, the traditional energy Internet usually could not meet requirements. Integrating mobile-edge computing makes energy Internet convenient for data acquisition,processing, management, and accessing. In this paper, we propose a novel framework for energy Internet to improve random access possibility and reduce transmission latency. This framework utilizes the local area network to collect data from users and makes conducting data compression for energy Internet possible. Simulation results show that this architecture can enhance random access possibility by a large margin and reduce transmission latency without extra energy consumption overhead.

An intelligent wireless transmission toward 6G

With the deployment and commercial application of 5G,researchers start to think of 6G,which could meet more diversified and deeper intelligent communication requirements.In this paper,a four physical elements,i.e.,man,machine,object,and genie,featured 6G concept is introduced.Genie is explained as a new element toward 6G.This paper focuses on the genie realization as an intelligent wireless transmission toward 6G,including sematic information theory,end-to-end artificial intelligence(AI)joint transceiver design,intelligent wireless transmission block design,and user-centric intelligent access.A comprehensive state-of-the-art of each key technology is presented and main questions as well as some novel suggestions are given.Genie will work comprehensively in 6G wireless communication and other major industrial vertical,while its realization is concrete and step by step.It is realized that genie-based wireless communication link works with high intelligence and performs better than that controlled manually.