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During the service period of communication satellite systems, their performance is often degraded due to the depletion mechanism. In this paper, the grey system theory is applied to the multi-state system effectiveness evaluation and the grey Lz-transformation ADC (availability, dependability and capability) effectiveness evaluation model is constructed to address the characteristics of the communication satellite system such as different constituent subsystems, numerous states and the inaccuracy and insufficiency of data.

The model is based on the ADC effectiveness evaluation method, combined with the Lz transformation and uses the definite weighted function of the three-parameter interval grey number as a bridge to incorporate the possibility of system performance being greater than the task demand into the effectiveness solution algorithm. At the same time, using MATLAB (Matrix laboratory) to solve each state probability, the same performance level in the Lz transform is combined. Then, the system effectiveness is obtained by Python.

The results show that the G-Lz-ADC model constructed in this paper can accurately evaluate the effectiveness of static/dynamic systems and certain/uncertain system and also has better applicability in evaluating the effectiveness of the multi-state complex system.

The G-Lz-ADC effectiveness evaluation model constructed in this paper can effectively reduce the complexity of traditional effectiveness evaluation models by combining the same performance levels in the Lz-transform and solving the effectiveness of the system with the help of computer programming, providing a new method for the effectiveness evaluation of the complex MSS. At the same time, the weaknesses of the system can be identified, providing a theoretical basis for improving the system’s effectiveness.

The possibility solution method based on the definite weighted function comparing the two three-parameter interval grey numbers is constructed, which compensates for the traditional calculation of the probability based on numerical values and subjective preferences of decision-makers. Meanwhile, the effectiveness evaluation model integrates the basic theories of three-parameter interval grey number and its definite weighted function, Grey−Markov, grey universal generating function (GUGF), grey multi-state system (GMSS), etc., which is an innovative method to solve the effectiveness of a multi-state instantaneous communication satellite system.

The purpose of this paper is to develop an analytic hierarchy process (AHP) method in safety risk assessment on communication system based on satellite constellations through constructing safety risk index system.

An empirical study using the AHP was carried out to find the relative weights of those assessment criterion and sub‐objectives of subsystem. Then the risk scores of 15 sub‐objectives and four subsystems were calculated applying the AHP method according to the assessment result of experts.

According to the overall results from the estimation of experts the safety risk priority of net application is the highest and the safety risk priority of attack on physical equipment is the lowest. This explained that the possibility of a war in today's era, in which peace and development is the theme is very small, and risk prevention should focus more on the defense of network attacks from enemies.

This paper provides a positive analysis of safety risk for a communication system based on satellite constellations and gives an opinion in accordance with the assessment result.

An AHP method was applied in the security risk assessment of communications systems on satellite constellation and the estimation of facing risk situation of the satellite communication system was presented according to the opinion of experts.

Communication infrastructure assets present a compelling investment opportunity for investors interested to tap into the technology-driven and innovation-led infrastructure segments, given the need for intensified capital deployment to prepare for the future substantial flow in volume and velocity of information. These communication infrastructure assets exist either in the segments of satellite or telecommunication infrastructure. This paper intends to empirically assess the performance attributes of listed satellite and telecommunication infrastructure over January 2000–June 2019. Sub-period performance dynamics of listed satellite and telecommunication infrastructure in the pre-GFC (January 2000–June 2007) and the post-GFC (July 2009–June 2019) investment horizons are provided.

Nineteen-year monthly total returns over 2000–2019 were used to analyse the risk-adjusted performance and portfolio diversification potential of both listed satellite and telecommunication infrastructure. The mean-variance portfolio optimisation framework using the full period and post-GFC ex-post returns, risk and correlation coefficient of listed satellite and telecommunication infrastructure and other financial assets was developed to determine the added-value benefits of listed satellite and telecommunication infrastructure in an optimised investment framework.

Listed satellite and telecommunication infrastructure delivered mixed investment performance. They were highly volatile and there was a significant discount in total return performance against the other asset classes in the full and pre-GFC periods. However, listed telecommunication infrastructure delivered stronger performance in the post-GFC period across all performance measures. Listed satellite and telecommunication infrastructure offered strong diversification benefits for investors across all investment horizons. Further, the inclusion of listed telecommunication infrastructure in both the full period and post-GFC mixed-asset investment framework was also empirically justified.

Communication infrastructure assets such as satellite and telecommunication infrastructure are the key infrastructure assets to ensure the seamless operation of and interaction with modern technology going forward. Whilst being a small proportion of the overall infrastructure asset class universe, the $2.1 trillion progressively expanding listed communication infrastructure sector is having an important role to stimulate investor capital deployments in high quality and future-proof communication infrastructure assets. Listed satellite and telecommunication infrastructure assets are an opportunistic investment given their future growth potential and are seen as a suitable fit for investors with a secular investment profile.

Despite the infrastructure asset class being the focus of growing attention and empirical analysis, no previous studies have empirically investigated the listed satellite and telecommunication infrastructure sectors. This is the first published empirical research analysis that aims at articulating the investment attributes of listed satellite and telecommunication infrastructure as a route for exposure in technology-related infrastructure assets. This research validates and informs practical property investment decision-making for investors seeking exposure in the increasingly important communication infrastructure assets sector.

Two high‐powered satellites built by Hughes Space and Communications Company (HSC) will bring true direct broadcast satellite (DBS) service to homes throughout North America starting in early 1994.

This paper aims to investigate the fast attitude coordinated control problem for rigid satellite swarms with communication delays.

Based on behavior‐based control approach, the attitude control system is designed to guarantee that the attitude of the satellite swarm converge to a dynamic reference state in finite time. A fast sliding mode is developed to improve the convergence rate and robustness of the control system. All the effects of communication delays, parameter uncertainties and external disturbances are taken into account simultaneously, and the communication topology of the satellite swarm can be arbitrary types. Numerical simulations are provided to demonstrate the analytic results.

Despite the existence of communication delays, parameter uncertainties and external disturbances, the stability of the closed‐loop system can be successfully guaranteed and the proposed control strategies are effective to overcome these unexpected phenomena subject to arbitrary communication topology.

This paper introduces a fast terminal sliding mode control method which can guarantee the fast convergence of the attitude state of the satellite swarm in the presence of communication delays, switched communication topology, parameter uncertainties and external disturbances.

This paper aims to implement quality of service(QoS) dynamic optimization for the integrated satellite-terrestrial network(STN) of the fifth-generation Inmarsat system(Inmarsat-5).

The structure and operational logic of Inmarsat-5 STN are introduced to build the graphic evaluation and review technique(GERT) model. Thus, the equivalent network QoS metrics can be derived from the analytical algorithm of GERT. The center–point mixed possibility functions of average delay and delay variation are constructed considering users' experiences. Then, the grey clustering evaluation of link QoS is obtained combined with the two-stage decision model to give suitable rewards for the agent of GERT-Q-learning, which realizes the intelligent optimization mechanism under real-time monitoring data.

A case study based on five time periods of monitoring data verifies the adaptability of the proposed method. On the one hand, grey clustering based on possibility function enables a more effective measurement of link QoS from the users' perspective. On the other hand, the method comparison intuitively shows that the proposed method performs better.

With the development trend of integrated communication, STN has become an important research object in satellite communications. This paper establishes a modular and extensible optimization framework whose loose coupling structure and flexibility facilitate management and development. The grey-clustering-based GERT-Q-Learning model has the potential to maximize design and application benefits of STN throughout its life cycle.

The purpose of this paper is to develop user friendly software with the minimum error and maximum performance in a form of remote sensing satellites evaluation software for estimation of weights and ranks of the remote sensing satellite plans, to decrease risk of management decisions.

The analytic hierarchy process (AHP) as a comprehensive framework for strategic decision making is used to arrive at the weights of criteria and sub‐criteria of remote sensing satellites. The Ms‐Access software is written to compute the ranks of the remote sensing satellite plans based on the relative weights of inputs and then, the outputs from AHP are shown as a numerical graph and generates the Ms‐Access database.

One of the main objectives of this paper is an attempt to access this skill that compare several remote sensing satellite plans on quantity and quality point of view by several effective criteria such as mass, power consumption and cost of satellites, in addition to the remote sensing subsystem, communication subsystem, telemetry, tracking and control subsystem, attitude determination control subsystem and their own sub‐criteria.

It is hard in just one paper, to gather lots of information about remote sensing satellite systems, use a new methodology that is unknown for aerospace engineering, and talk about an innovative software.

This paper provides helpful evaluating software which has a data bank that it is very useful and impartial advice for space strategy's managing organization to compare several plans.

This study provides low cost, time‐saving, and high‐performance remote sensing satellite evaluation software and gives valuable information and guidelines which help management decisions of aerospace organization.

The use of LEO satellite systems has become widespread throughout the world, not only from the services standpoint but in large scale communication networks as well, as they make it possible to communicate from any point of the globe. Lately, the communications in the satellite field have been markedly developed thanks to the Low Earth Orbit (LEO) satellites and GEO satellite orbit. This paper deals with the main survey of these networks by a demonstration of satellite constellations constitutions and the different interfering factors, namely the number of satellites in each orbit, modelling the HANDCHECK problems or Handover satellite probably blocking. In order to preserve the information, to make sure that a seamless communication between two satellite zones is ensured the Hand check should continuously be present in satellite networks. Although the achievement of such schemes is routine work in the laboratory, nontrivial problems emerge in long-distance applications. At present, the only suitable system for long-distance quantum communication is photons. The essential work carried out in our research laboratory concerns an approach in software development of the implementation of Quantum Key Distribution (QKD) Networks with LEO orbit satellites and a reduction of the telecommunication interruption risks, which indeed will provide a better communication quality.

The devastating impact of catastrophic disasters on terrestrial infrastructure requires the adoption of alternative technology solutions among humanitarian organizations. The purpose of this paper is to analyze the role of the most commonly used satellite technologies in relief logistics: imagery and mapping, portable global positioning system (GPS) positioning devices, telecommunications, and GPS vehicle tracking.

The paper examines both the benefits and limitations of satellite technologies in light of the existing literature and through a complementary questionnaire survey with field workers involved in humanitarian operations in the aftermath of the 2010 Haiti earthquake.

The results show that the use of satellite technologies can facilitate most of the key logistics challenges encountered by relief actors. However, they also highlight important barriers within humanitarian organizations such as the lack of skilled workers and high costs, underlining the need for long-term training, resource investments, and cooperation between users and technology providers.

The research findings remain valid only in the context of catastrophic disaster responses, which lead to similar destructions, logistical problems, and needs for satellite technologies.

This paper shows how satellite technologies can support humanitarian professionals in the field. It also provides policy recommendations that can facilitate the use of these technologies.

The applications of satellite technologies within humanitarian supply chains are not well-defined in the literature. This paper is the first to be dedicated to analyze the role of the main satellite technologies used in a relief logistics setting.

Satellite networking will be an important component of future ubiquitous communications systems. Satellite networks will be especially useful to interconnect remote sensor networks. Therefore, satellite networks should provide the needed QoS, differentiation of services and at the same time keep the required scalability. The purpose of this paper is to propose a new Diffserv‐based scheme of bandwidth allocation during congestion, called proportional allocation of bandwidth (PAB).

The paper suggests a method for implementing PAB without storing per‐flow state, which makes the scheme scalable and simple and shows, by simulation, the advantages of using PAB in IP satellite networks.

The paper finds that PAB can be used in geostationary earth orbit, MEO and low earth orbit satellite networks. In PAB, during congestion all flows get a share of IP available bandwidth, which is in proportion to their subscribed information rate.

The simulations described in this paper show that the performance of PAB scheme is good on congested satellite networks.