Virtualized High Throughput Satellite Gateway with a Global Bandwidth Management Method

With the development of new satellite payload technology, in order to improve the utilization of system resources, research is based on software-defined network (SDN) and network function virtualization (NFV) gateway architecture. Based on this architecture, the system realizes global resource management and overall data distribution, which can solve the problem of resource allocation and maximum/minimum rate guarantee between different VNO terminals under different beams, different gateways, and different satellites. For this, a global bandwidth management method can be used which is mainly a process of management to control the traffic on a communication link. The proposed global resource management and control method can be based on the rate guarantee value of the VNO/terminal configured in the system as the basic limiting condition and reallocate the rate guarantee value limiting parameter according to the resource application status of the online terminal. The method can maximize the resource utilization of the entire satellite communication system and satisfy the resource request of the user terminal as much as possible.

Genetic Algorithm-Based Hybrid Spectrum Handoff Strategy in Cognitive Radio-Based Internet of Things

In Cognitive radio-based Internet of Things (CR-IoT) systems, the return of the primary user (PU) causes the secondary user (SU) that is communicating to face the spectrum handoff problem. In the process of spectrum handoff, the user terminal can’t get the idle channels in time because of the unknown channel usage state. To solve this problem, a hybrid spectrum handoff algorithm based on the channel idle probability is proposed. The algorithm considers the regularity of PU activities in space and time, defines the idle probability of channels from the perspective of week attributes and time periods, obtains the optimal time period length using genetic algorithm, generates a channel idle probability table, and provides the target channel sequence for SUs in combination with the proposed channel ordering scheme. Simulation results show that the hybrid spectrum switching algorithm based on the channel idle probability can reduce the energy consumption of SUs during spectrum switching, reduce the communication interruption rate, enable SUs to find idle channels faster and reduce the number of sensing times.

Construction of College English Mobile Learning Model Based on Distributed Terminal

The quality of English teaching cannot be separated from the students’s accumulation and mastery of vocabulary, and sufficient vocabulary can ensure that students feel easy and comfortable in the language application. However, there are still some problems in teaching English vocabulary in colleges and universities, such as single presentation method, lack of real context, and other difficulties. With the rapid development of mobile Internet, the share of smart mobile devices among college students has increased, which in turn has laid the foundation for the development of new learning modes. The mobile terminal-mediated learning mode in English classroom teaching has become a hot topic of research nowadays, of which English vocabulary teaching has become a typical example. This paper is designed as a system model of edge computing, in which the user terminal device can connect wirelessly with each MECS and offload the tasks to be processed on the MECS, which helps the user terminal device to process and return the results to the user terminal device. The research in this paper also provides a basis for students’ independent and lifelong learning of English words and for schools’ information technology to serve English vocabulary teaching and learning.

Multi-RAT Orchestration Method for Heterogeneous Wireless Networks

Currently, energy efficiency (EE) of wireless communication is essential where many wireless networks with different Radio Access Technologies (RATs) coexist together. The RATs can be effectively selected and managed on a higher level to achieve maximum EE and save energy, e.g., save batteries. The approach to wireless traffic steering in mobile networks with a proof-of-concept solution is presented in this paper, owing to the developed high-level multi-RAT (multi-Radio Access Technology) heterogonous network orchestration approach. Based on the high-level network orchestrator, which traces network indicators, it is possible to decrease the user mobile terminal energy consumption, keeping traffic speed at an adequate level. The solution discussed was implemented in an experimental testbed with Software Defined Radio transmission systems. Downlink and uplink data links were toggled among different RATs according to the decisions that were taken by the end-to-end multi-RAT orchestrator based on the received proper network traffic-related indicators. The authors focused on finding an adequate algorithm that allowed for reduced power usage in the user terminal and made the attempt to verify how to reach the power reduction without introducing RAT-specific rules. The results showed that the proposed orchestration EE reduction was observed (from 11% to 42% for two different scenarios) in relation to the single LTE network deployment. The orchestration compared to the Wi-Fi network does not provide EE gain (−7% and 0%, respectively), but allows the user to achieve a higher data rate (23% and 39% gain, respectively), thus keeping the energy efficiency at almost the same level.

Small Satellites Constellations and Their Impact on CBRNe Management in Africa

A wave of small satellites massive constellations, in the range of hundreds of units each, is progressively populating the Low Earth Orbit (LEO) with a low-price, and varied, offer of Telecom (speed band) and Earth Imaging services (Starlink, Planet, One Web, etc.). It is a market - driven trend based on new satellite interlocking technologies, which cut down the supplier costs of launch and in orbit operations compared to the traditional technology based on big (and much heavier) geostationary satellites operating at high altitudes. This is a disruptive phenomenon especially for the developing world, where such vital services have always been hard to access, and their use therefore remained scarce, not consolidated, or even completely missing. Among these, Emergency management is definitely crucial. The geographical focus of this study is Africa and it deals not only with Institutional PRS users but with a wider potential context (corporations, private subjects, etc.). It clearly appears that a general degree of “Country readiness” toward Space technology and organization is necessary for these initiatives to take place. This can be achieved through certified international cooperation. The authors then, based on an estimated demand Model for services with their relative pricing corresponding to a cost-designed constellation of small microsatellites, presented already, among other, at several International Astronautical Federation(IAF)Symposia on Space Economy, simulate the resulting type of services available: TLC by band types and relative upload and download rates, Earth imaging by refresh rates and optical quality and resolution, Ground segment configuration for signal backhauling and user terminal receiving.. This info isapplied to a specific African Country case (Nigeria) whose significance emerged over other Countries after the application of comparative grids. Finally, an insight on the specifically configuration of services for Chemical, Biological, Radiological, Nuclear, and Explosive (CBRNe) like management by local users, both maritime and land, with the relative costs, is offered. This is consequently left open for follow ups and discussion, due to the customer – design, project financing approaches of this Model programme.

Ku/Ka band diplexer based on thin-film technology for small ground-segment user terminals

This paper describes the outcome of the “Small user TErminal multi band DIplexer” project where the goal is the validation of novel SMD-compliant planar diplexer. The real application scenario concerns an integrated multi-band radio terminal for ground-segment satellite links. The advantageous and novel approach involves the simultaneous use of three different well-established concepts: a microstrip low-pass filter, a substrate integrated waveguide high-pass filter, and the thin-film technology as manufacturing process. The proposed topology applied to a planar alumina-based design guarantees a 15 × 11.1 mm2 footprint and the best integration with surface mountable soldering process over standard PCB technology. Achieved performance and resilience to environmental toughness are suitable for consumer-oriented satellite links or man-pack applications. The designed component targets the Ku 10.7–12.75 (RX) and Ka 27.5–30 (TX) GHz bands but the layout can be easily tuned across the spectrum. The described solution has been manufactured and validated. Thermal cycling and mechanical tests have been carried out to prove the high technology readiness level of the proposed device.

Computer Simulation of Ideological and Political Teaching under Big Data of Complexity

This study is to discuss the application of computer simulation technology (CST) in ideological and political teaching (I&P teaching) and promote the reform of ideological and political teaching in the era of big data. In this study, a set of computer simulation system for I&P teaching is constructed, and targeted research is launched from this. The main research results are as follows: Firstly, a computer simulation system for ideological and political teaching is designed based on the Apriori algorithm and other theoretical foundations. The system includes a user layer, a business layer, and a data layer. The main modules of the system include the website (WEB) server, Mail server, and user terminal. Secondly, the system is tested accordingly. The performance test and function test results reveal that when the maximum number of concurrent users is 500, the system can run normally with the maximum response time of 6.6 s and the good condition of various functions, so it can meet the actual needs of universities. Finally, in comparison with the conventional I&P courses, the proposed system can effectively improve the attitudes towards I&P courses of students, increase their satisfaction and acceptance of I&P teaching, and contribute to the mastery of knowledge. Therefore, the designed system can realize a good actual teaching effect and show reliable application value. In addition, the results of this study can provide scientific and effective reference materials for subsequent research on I&P teaching.

Granular VNF-Based Microservices

The dawn of the 5G commercialization era brings the proliferation of advanced capabilities within the triptych of radio access network, end user devices, and edge cloud computing which hopefully propel the introduction of novel, complex multimodal services such as those that enlarge the physical world around us like mobile augmented reality. Managing such advanced services in a granular manner through the emerging architectures of microservices within a network functions virtualization (NFV) framework allows for several benefits but also raises some challenges. The aim of this chapter is to shed light into the architectural aspects of the above-envisioned virtualized mobile network ecosystem. More specifically, and as an example of advanced services, the authors discuss how augmented reality applications can be decomposed into several service components that can be located either at the end-user terminal or at the edge cloud.