The simulation modelling and performance analysis of low earth orbit satellite communication networks for personal communications

This paper extends previous research efforts related to the simulation performance modelling and analysis of satellite communication networks. Specifically, the use of low earth orbit (LEO) satellite networks for personal communications is examined. Six different satellite constellation configurations are investigated in a packet‐switched operating environment. Performance metrics examined are the end‐to‐end packet delay and the utilization of satellite channels in the dynamic environment. Realistic and accurate models of the physical satellite network and its terrestrial transmitters require that numerous operating characteristics and assumptions be specified. These are based on proposed design requirements of commercial systems, such as Iridium. Via the use of simulation, we show the relative delay and utilization performance of differing satellite network architectures. From these simulation models, mathematical metamodels are derived for the system delays. These innovative models are used to predict the delay performance of different network architectures not previously simulated. Comparison of these metamodels with simulation results show that metamodels provide an accurate means for performance prediction. Copyright © 1999 John Wiley & Sons, Ltd.     

A modified power control scheme for remedying the effects of traffic nonuniformity in LEO satellite communications systems

It has been shown in our previous studies that the geographical traffic nonuniformity considerably affects the performance of the low earth orbit satellite communications systems. In this paper, a new scheme for improving the throughput characteristics of these systems at nonuniform traffic distribution is proposed. In this method, some parts of the users under the satellite which is flying over the area with high traffic load are assigned to its neighbor satellites with lower transmitting power levels. It is shown that the method equalizes the traffic loads of the satellites to some degree and, hence, can improve the throughput characteristics of the system.     

Towards the implementation of advanced random access schemes for satellite IoT

Machine‐to‐machine (M2M) communications being pivotal for internet of things (IoT) networks are characterized by low‐cost, low complexity, and often energy constrained terminals with low traffic duty cycle. Satellite networks provide an attractive low‐cost solution for such application, in particular when the terminals (both fixed and mobile) are distributed over a wide geographical area not well served by terrestrial infrastructure. An ALOHA random access (RA) scheme is a natural candidate for M2M communications since it is well matched to sporadic traffic, and it requires little terminals coordination. However, the classical ALOHA scheme suffers from a low throughput when operated in a load region requiring low probability of packet loss. To overcome this intrinsic ALOHA limitation, in the last decade, a lot of effort has been devoted to the investigation of evolutions of the ALOHA scheme reducing the probability of destructive packet collisions thus making it more attractive for satellite IoT. In such context, the Contention Resolution Diversity ALOHA (CRDSA) scheme and the Asynchronous Contention Resolution Diversity ALOHA (ACRDA) have emerged as promising solutions thanks to their high spectral efficiency achievable with low packet loss probability. The results reported in literature are however assuming ideal demodulator performance. This paper investigates the design and optimization of RA burst demodulator algorithms for single‐frequency and multifrequency CRDSA and ACRDA. It evaluates the performance of such algorithms in a number of system scenarios of practical interest and studies the impact of relevant system parameters on several performance metrics.     

A model for the handover traffic in low earth-orbiting (LEO) satellite networks for personal communications

The spectacular growth of cellular telephone networks has demonstrated the demand for personal communications. Communication systems based on low earth orbit (LEO) constellations of satellites seem to be an adequate approach to achieve a world-wide network. When defining the capacity in terms of satellite circuits, the network designer has to take into account the handover traffic. Unfortunately, in a LEO communication network where handover is most often due to the network nodes motion, handover traffic models for terrestrial cellular networks cannot be used. Hence specific models must be developed. This paper proposes an analytical model for the handover in LEO satellite networks. This model is applied to different network configurations and compared to discrete-time simulations. Simulation results agree with those obtained from the analytical model.     

Standardized testing conditions for satellite communications on‐the‐move (SOTM) terminals

Performance validation of Satcom on‐the‐move (SOTM) terminals is becoming more important as the satellite operators continue to recognize the negative influence of suboptimal terminals on their satellite networks. Traditionally, SOTM testing is performed with actual operational satellites in field tests, which lack repeatability. The capability to repeat the conditions in which SOTM terminals are tested is important, especially when the performance of multiple terminals is compared. This contribution describes how the qualification test of SOTM terminals can be conducted in a laboratory environment so that repeatability can be ensured. A major advantage of a laboratory environment is the ability to test the complete terminal as if it was in the field of operation, yet without the involvement of real satellites effectively reducing the costs of testing. The main contributions of this paper are motion and shadowing profiles suitable for standardization of SOTM testing. Standardization of such profiles is necessary to guarantee a fair comparison of the performance of different terminals. Moreover, the paper presents the methodology for testing SOTM terminals at the Fraunhofer Facility for Over‐the‐air Research and Testing, * * * https://www.iis.fraunhofer.de/en/profil/standorte/forte.html the procedure used to obtain the proposed profiles and results of testing a Ka‐band SOTM terminal, taken as an example.     

Medium earth orbit optical satellite communication networks: Ground terminals selection optimization based on the cloud‐free line‐of‐sight statistics

In this paper, a methodology for the generation of cloud coverage time series correlated on both temporal and spatial domains and the estimation of cloud‐free line‐of‐sight (CFLOS) probability for a single optical ground station (OGS) and a network of OGSs (multiple OGS) for medium earth orbit (MEO) constellation satellite communication systems is presented. Spatial diversity is employed as a mitigation technique against cloud blockage to increase the availability of an OGS network (OGSN). In the second part of the paper, an effective algorithm based on the ant colony optimization (ACO) algorithm is proposed for the optimum selection of OGSs forming an OGSN. The proposed algorithm takes into consideration the spatial correlation between the OGSs. In the simulation results section, a MEO constellation system with 12 MEO satellites has been assumed. The integrated liquid water content (ILWC) statistical parameters that are necessary for the CFLOS time series are taken from ECMWF Re‐Analysis (ERA)‐Interim database, European Centre for Medium‐Range Weather Forecasts (ECMWF). Finally, numerical results for the optimum selection of OGSs using the proposed methodology are exhibited and commented. Interesting conclusions are drawn, and future work with technical challenges is briefly described.     

On the quality of VoIP with DCCP for satellite communications

We present experimental results for the performance of selected voice codecs using Datagram Congestion Control Protocol (DCCP) with CCID4 congestion control over a satellite link. We evaluate the performance of both constant and variable data rate speech codecs for a number of simultaneous calls using the ITU E‐model. We analyse the sources of packet losses and additionally analyse the effect of jitter, which is one of the crucial parameters contributing to Voice over IP (VoIP) quality and has, to the best of our knowledge, not been considered previously in the published DCCP performance results. We propose modifications to the CCID4 algorithm and demonstrate how these improve the VoIP performance, without the need for additional link information other than what is already monitored by CCID4. We also demonstrate the fairness of the proposed modifications to other flows. Although the recently adopted changes to TCP‐Friendly Rate Control specification alleviate some of the performance issues for VoIP on satellite links, we argue that the characteristics of commercial satellite links necessitate consideration of further improvements. We identify the additional benefit of DCCP when used in VoIP admission control mechanisms and draw conclusions about the advantages and disadvantages of the proposed DCCP/CCID4 congestion control mechanism for use with VoIP applications. Copyright © 2012 John Wiley & Sons, Ltd.     

Essentiality of managing the resource information in the coordinated fog‐to‐cloud paradigm

Fog‐to‐cloud (F2C) computing is an emerging computational platform. By combing the cloud, fog, and IoT, it provides an excellent framework for managing and coordinating the resources in any smart computing domain. Efficient management of these kinds of diverse resources is one of the critical tasks in the F2C system. Also, it must be considered that different types of services are offered by any smart system. So, before managing these resources and enabling the various types of services, it is essential to have some comprehensive informational catalogue of resources and services. Hence, after identifying the resource and service‐task taxonomy, our main aim in this paper is finding out a solution for properly organizing this information over the F2C system. For that purpose, we are proposing a modified F2C framework where all the information is distributively stored near to the edge of the network. Finally, by presenting some experimental results, we evaluate and validate the performance of our proposing framework.     

Rainfall propagation impairments for medium elevation angle satellite‐to‐earth 12 GHz in the tropics

Rain attenuation is the dominant propagation impairment for satellite communication systems operating at frequencies above about 10 GHz. The rainfall path attenuation at 12.255 GHz measured at Universiti Sains Malaysia (USM) for 4 years (2 January to 5 December) is presented. This paper presents an empirical analysis of rain rate and rain attenuation cumulative distribution functions obtained using 1‐min integrated rainfall data and comparison of the measured data with data obtained from well‐established rain model attenuation predictions. Copyright © 2008 John Wiley & Sons, Ltd.     

On the design considerations of solid-state power amplifiers for satellite communications: A systems perspective

Conventional solid-state power amplifier (SSPA) design approach isolates radio frequency (RF) design from communication theory. In this paper, a unified SSPA design approach is proposed, which optimizes SSPA parameters (bias voltage and input RF signal power) to minimize total DC power consumption while satisfying received SNR constraint specified by the link budget. The effect of SSPA nonlinearity is quantified by the error vector magnitude measured at its output and the corresponding received SNR degradation is analyzed. Using the quantitative metrics for received SNR, it is possible to evaluate highly nonlinear SSPA classes such as Class-B or deep-Class AB, which are normally not considered in conventional SSPA design approach to be used in satellite communication applications.     

Robust security framework for DVB‐RCS satellite networks (RSSN)

Satellites represent a solution for Internet access in locations with no other telecom infrastructures, for example, on high mobility platforms such as planes, ships or high‐speed trains, or for disaster recovery applications. However, due to peculiar characteristics, satellite networks are prone to different security threats. In this paper, we introduce a novel, robust security architecture for securing digital video broadcasting‐return channel via satellite satellite networks, inspired by the robust security mechanism available in the Institute of Electrical and Electronic Engineers (IEEE) 802.11i wireless local area network. We propose an efficient authentication and key management mechanism, which is exploited through three round‐trips only, demonstrating that it is as secure as IEEE 802.11i. Furthermore, the simulation results show that the proposed security framework needs a very small data overhead and shows better performance than internet protocol security (IPSec), which is commonly used as an end‐to‐end security solution over internet protocol satellite networks. Copyright © 2015 John Wiley & Sons, Ltd.     

A model for the estimation of the carrier‐to‐noise plus total interference ratio between two adjacent dual polarized satellite links sharing the same frequency band

In modern satellite communications, matters such as frequency congestion, transmission of dual polarized carriers and increase of the number of geostationary satellites in use, necessitate the implementation of interference analysis in neighbouring networks so as to ensure satisfactory quality of service. In this paper, a recently proposed model for the prediction of the degradation of the carrier‐to‐interference ratio due to differential rain attenuation and cross‐polarization, which is applicable only for the noise‐dominant case, has been properly modified to include the general case. The proposed model is based on the lognormal assumption for the point rainfall rate statistics and the convective raincell model. Due to complexity of the proposed analysis, some simple regression‐derived formulas have been generated forming a very useful tool for the system engineer. The elaborations of numerical results examine the influence of various parameters upon the total availability performance and the optimum utilization of the geostationary orbit. Copyright © 2005 John Wiley & Sons, Ltd.     

Evolution of satellite communications: Integration of ETSI BSM and DVB‐RCS for future satellite terminals

The main added value of the European Telecommunications Standards Institute broadband satellite multimedia (ETSI BSM) architecture is the definition of the Satellite Independent‐Service Access Point (SI‐SAP) protocol interface, which formally separates Satellite Dependent (SD) from SI layers, thus enabling the implementation of powerful vertical QoS mapping strategies. On the other hand, DVB‐S2/RCS satellite standard is considered the driving technology to integrate satellite with terrestrial infrastructure and provide up‐to‐date services. This paper focuses on the integration of ETSI BSM architecture and DVB‐RCS technology, by analysing the adaptations needed on real DVB‐RCS terminals to be interoperable with the SI‐SAP interface. To this end, the detailed design of an underlying architecture taking into account required adaptations and new functionalities is proposed. The possible further evolutions of the BSM specification are also highlighted, showing the potential for the development of future devices integrating both DVB‐RCS and ETSI BSM architectures also in view of the recent upgrade to the DVB‐RCS2 standard. The paper also validates the SI‐SAP QoS functionalities and proves the performance benefits in terms of QoS and quality of experience of Web‐browsing by means of a satellite emulator developed fors this aim. Copyright © 2015 John Wiley & Sons, Ltd.     

Adaptive Coding and Modulation‐enabled satellite triple play over DVB‐S2 (Digital Video Broadcasting ‐ Satellite ‐ Second Generation): a techno‐economic study

This article looks at the techno‐economic perspectives of the use of DVB‐S2 (Digital Video Broadcasting ‐ Satellite ‐ Second Generation) and its unique feature, Adaptive Coding and Modulation (ACM) in the provision of satellite triple play. For this study, current market economic data were used, in conjunction with technical results derived within the European Union‐funded IST IMOSAN project. IMOSAN (Integrated Multi‐Layer Optimisation in DVB‐S2 Satellite Networks) succeeded in realising the provision of satellite triple play over an interactive DVB‐S2/DVB‐RCS (Return Channel via Satellite) platform. The ACM feature of DVB‐S2 was exploited, yielding increased spectrum efficiency and thus decreasing service cost. One‐user‐per‐terminal scenarios are examined, as well as terrestrial redistribution of satellite services to a group of users via WiMAX. Copyright © 2012 John Wiley & Sons, Ltd.     

Co‐ordination channels for digital satellite news gathering (DSNG)

This paper presents, in Section 1, a new approach to realising co‐ordination channels for digital satellite news gathering (DSNG). The key element of the approach to the co‐ordination channels is a direct‐sequence spread‐spectrum processing of the data to be transmitted which allows for the realization of an in‐band transmission of the co‐ordination channel signals overlaying the DSNG main channel, the part of the system which is responsible for the transmission of the audio/video signal on a point‐to‐point basis. The system is analysed in theory, simulation, and measurement with respect to system performance and degradation of the DSNG main channel. It shows superior system performance combined with a maximum of operational simplicity while the degradation of the DSNG main channel remains affordably low. Section 2 describes the DVB‐DSNG system for co‐ordination channels which incorporates many elements of the system presented in the first part but is modified in some details in order to increase system flexibility. One of these details concerns the possibility to perform in‐band transmission as well as transmission in the roll‐off frequency space of the DSNG main channel. In‐band transmission has the advantage of great operational simplicity and is nearly identical to the system presented in Section 1. What characterizes the transmission in the roll‐off frequency space is the fact that it is more robust and DSNG main channel degradation is negligible, but this at the price of decreased operational simplicity. Copyright © 2000 John Wiley & Sons, Ltd.     

Simulation analyses of weighted fair bandwidth‐on‐demand (WFBoD) process for broadband multimedia geostationary satellite systems

Advanced resource management schemes are required for broadband multimedia satellite networks to provide efficient and fair resource allocation while delivering guaranteed quality of service (QoS) to a potentially very large number of users. Such resource management schemes must provide well‐defined service segregation to the different traffic flows of the satellite network, and they must be integrated with some connection admission control (CAC) process at least for the flows requiring QoS guarantees. Weighted fair bandwidth‐on‐demand (WFBoD) is a resource management process for broadband multimedia geostationary (GEO) satellite systems that provides fair and efficient resource allocation coupled with a well‐defined MAC‐level QoS framework (compatible with ATM and IP QoS frameworks) and a multi‐level service segregation to a large number of users with diverse characteristics. WFBoD is also integrated with the CAC process. In this paper, we analyse via extensive simulations the WFBoD process in a bent‐pipe satellite network. Our results show that WFBoD can be used to provide guaranteed QoS for both non‐real‐time and real‐time variable bit rate (VBR) flows. Our results also show how to choose the main parameters of the WFBoD process depending on the system parameters and on the traffic characteristics of the flows. Copyright © 2005 John Wiley & Sons, Ltd.     

BPSK and QPSK non‐linear satellite communication system performance in the presence of cochannel interference

Taking the uplink and downlink cochannel interference and noise into account, the analytical expressions are derived for determining the bit error probability in detecting a binary phase‐shift‐keying (BPSK) and a quaternary phase‐shift‐keying (QPSK) Gray coded signal, transmitted over a satellite system exhibiting amplitude modulation‐to‐amplitude modulation (AM/AM) conversion effects and amplitude modulation‐to‐phase modulation (AM/PM) conversion effects. On the basis on the derived theoretic formulae, using real‐life system parameters, numerical results are obtained and presented. We point out the explicit comparisons of satellite communication system performance obtained when a satellite transponder amplifier is modelled by a hard‐limiter and those obtained when both AM/AM and AM/PM non‐linearities of the satellite transponder amplifier are taken into consideration. Copyright © 2003 John Wiley & Sons, Ltd.     

On the secrecy performance of integrated satellite‐aerial‐terrestrial networks

This paper investigates secure transmission of an integrated satellite‐aerial‐terrestrial network (ISATN), where multiple eavesdroppers (Eves) attempt to overhear the satellite signals cooperatively. The ISATN adopts an unmanned aerial vehicle (UAV) equipped with multiple antennas as a relay with threshold‐based decode‐and‐forward (DF) protocol. By assuming that perfect instantaneous channel state information (CSI) of the satellite‐UAV link and the statistical CSI of the UAV‐user link are available, we first propose a beamforming (BF) scheme for maximizing the achievable secrecy rate (ASR) of the considered network. Then, we derive the analytical expressions of the secrecy outage probability (SOP) and ergodic secrecy rate (ESR) of the considered system with the BF strategy under an assumption that the satellite‐UAV link undergoes the shadowed‐Rician fading, while the UAV‐user link experiences the correlated Rayleigh fading. Finally, numerical results are given to demonstrate the superiority of the proposed BF scheme against zero forcing (ZF) and maximal ratio transmission (MRT) schemes and the validity of the secrecy performance analysis.     

Leveraging multiuser diversity for adaptive hybrid satellite‐LTE downlink scheduler (H‐MUDoS) in emerging 5G‐satellite network

In order to achieve ubiquitous coverage and service continuity in future 5G network, satellite‐based access is the best solution to complement the terrestrial LTE‐A. In light of this, we introduce a channel‐aware hybrid scheduling technique on the basis of satellite‐LTE spectrum sharing. According to the user‐experienced channel, base stations (eNodeB) and the satellite will work cooperatively. The eNodeB mainly provides service in urban area for high density population. Meanwhile, the satellite will perform either offloading, providing service for under‐served users, or extra coverage for users in rural and remote areas having no coverage of eNodeB. Leveraging the multiuser diversity, we implement a new metrics computation method for hybrid satellite‐LTE downlink scheduler (H‐MUDoS). Compared with other existing schedulers, simulation results clearly demonstrate the high performance of H‐MUDoS in terms of spectral efficiency in addition to improvement of the quality‐of‐service requirements and capacity maximization.     

Digital video broadcasting over satellite (DVB‐S): a system for broadcasting and contribution applications

The general system concepts for digital television transmission and broadcasting by satellite, developed within the European digital video broadcasting (DVB) Project and standardized by ETSI are described. The system (EN 300 421) is designed to provide direct‐to‐home (DTH) multi‐programme TV services in the BSS and FSS bands and is addressed to consumer integrated receiver decoders (IRDs), as well as collective antenna systems (SMATV) and cable television head‐end stations, with a likelihood of remodulation. The system operational modes have been extended in 1998 (EN 301 210) to cover also ‘contribution’ applications by satellite, such as conveying vision and sound material between TV studios, or from remote locations directly to the broadcaster's premises through light and portable up‐link terminal digital satellite news gathering (DSNG). The exploitation of the multiplex flexibility allows the use of the transmission capacity for a variety of TV service configurations. The use of flexible and advanced error protection techniques, based on the concatenation of Reed‐Solomon and convolutional codes (with Viterbi decoding), allows optimum adaptation to different satellite transponder characteristics, i.e. bandwidth and power, providing high service quality and availability with small receiving antennas (DTH applications) or transmitting terminals (DSNG applications). Copyright © 2000 John Wiley & Sons, Ltd.