International Journal of Satellite Communications and Networking最新文献

{"title":"A high-efficiency frequency synchronization scheme for low Earth orbit satellite communications based on dynamic game theory","authors":"Wen Liu,&nbsp;Wei Cai,&nbsp;Lizhe Liu,&nbsp;Dongdong Wang,&nbsp;Wenliang Lin,&nbsp;Ke Wang,&nbsp;Zhongliang Deng,&nbsp;Yaohua Deng,&nbsp;Da Wan,&nbsp;Zewen Dong,&nbsp;Junhe Hu","doi":"10.1002/sat.1502","DOIUrl":"10.1002/sat.1502","url":null,"abstract":"<div>\u0000 \u0000 <p>The rapid development of satellite internet networks has given rise to a new vision for the sixth generation of networking technology. However, the Doppler effect is relatively serious in satellite internet networks because a satellite moves quickly relative to a ground terminal. Therefore, there is an urgent need to study intelligent and dynamic synchronization methods to solve the problem of the rapidly changing Doppler frequency offset. Traditional methods do not consider the impact of spatial changes and typically focus on enhancing the estimation range or accuracy. We analyze various scenarios under phased array beam hopping and establish constraints between the terminal location, satellite ephemeris, subsatellite point track, elevation angle, and carrier frequency offset. We introduce dynamic game theory into frequency synchronization to optimize multiple Doppler estimation performance under rapidly changing channel conditions. We take the combination of carrier frequency offset estimation algorithm strategies at the current moment as the game entity. Simulation results demonstrate that the proposed method can achieve an estimation accuracy of 100 Hz and an estimation range of ±800 kHz. During the onboard test, the probability of achieving complete synchronization (when the synchronization success rate is 1) is 0.65, which is much higher than the 0.15 of the single method.</p>\u0000 </div>","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"42 2","pages":"97-122"},"PeriodicalIF":1.7,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135769881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time and phase alignment of distributed gateways: Theoretical analysis and experimental demonstration","authors":"Eriserdi Mollaymeri, Thomas Delamotte, Andreas Knopp","doi":"10.1002/sat.1500","DOIUrl":"https://doi.org/10.1002/sat.1500","url":null,"abstract":"Summary Very high throughput satellite systems have recently been developed to offer high‐speed connectivity, especially in remote areas, planes, and ships. The high data rates can be achieved by using a multibeam approach with an aggressive reuse of the available frequency resources. Due to the high number of user beams, the system must support a large aggregated bandwidth. Multiple‐gateway architectures are a necessary solution to sustain the immense bandwidth requirements. Multiple‐input multiple‐output (MIMO) feeder links have been proposed to address the ground segment design challenges of multiple‐gateway architectures. The deployment costs and the link availability performance can in particular benefit from this approach. However, to coordinate the operation of multiple gateways, high precision time and phase synchronization is necessary. In this paper, the effect of time and phase misalignment in MIMO feeder links is studied. The performance limitation due to imperfect time and phase distribution is analyzed. Synchronization via optical fiber is considered in this study. The accuracy of time distribution was verified through laboratory measurements. The impact of the residual timing error on the achievable system bandwidth was assessed. Results showed that several GHz of bandwidth can be supported. On the other hand, a recently proposed phase synchronization approach is considered as a promising candidate for MIMO feeder links. Its phase stability performance is assessed, and it is emphasized that requirements in terms of link outage are fulfilled.","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135926521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Univariate exploratory data analysis of satellite telemetry","authors":"Mv Ramachandra Praveen,&nbsp;Sushabhan Choudhury,&nbsp;Piyush Kuchhal,&nbsp;Rajesh Singh,&nbsp;Purnendu Shekhar Pandey,&nbsp;Antonino Galletta","doi":"10.1002/sat.1498","DOIUrl":"10.1002/sat.1498","url":null,"abstract":"<p>Large low Earth orbit satellite constellations require machine learning methods for enabling autonomy in health keeping of the satellites. Autonomy in health keeping entail's fault detection, isolation and reconfiguration. However, prior to model building, it becomes imperative to conduct exploratory data analysis of the data to gain an intuition of data and to decide the best model. Univariate exploratory data analysis has been carried out on a BUS CURRENT sensor of electrical power system of a low Earth orbit satellite to gain an understanding of data. Various aspects of data like presence of outliers, sampling frequency, missing values, comparison of imputation methods to fill missing values seasonality and trend analysis, stationarity test on data, rolling mean and autocorrelation and partial auto correlation plots have been made, and a detailed statistical analysis of results has been conducted.</p>","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"42 1","pages":"57-85"},"PeriodicalIF":1.7,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/sat.1498","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136236684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Base station location generation algorithm for satellite-terrestrial co-existence studies","authors":"Vijay Singh Bhadouria,&nbsp;Sucharita Chakraborty,&nbsp;Saket D. Buch,&nbsp;Subhash Chandra Bera","doi":"10.1002/sat.1501","DOIUrl":"10.1002/sat.1501","url":null,"abstract":"<div>\u0000 \u0000 <p>The enormous growth of mobile broadband traffic is a catalyst for expanding terrestrial communication systems and their integration with satellite communication systems. This results in sharing frequencies allocated to satellite communication systems with terrestrial systems. As this can lead to interference between the incumbent and the upcoming service, coexistence studies are conducted. In the case of sharing satellite uplink frequencies with terrestrial communication systems, interference from base stations (BSs) is dominant. While there are methods to estimate the number of BSs that may be deployed, it is unclear where the BSs will be located. The BS locations play a pivotal role in interference calculation, as the values of link budget parameters are highly dependent on the longitude and latitude of interfering transmitters. This article presents an intelligent method which balances network capacity and coverage for simulating base stations (BSs) in coexistence studies. A realistic BS distribution is generated using weighted K-means clustering (WKMC) algorithm and incorporating population density along with Haversine distance. The paper provides a case study of co-frequency, co-coverage interference in the satellite uplink in the C-band to demonstrate the impact of BS distribution on the results of coexistence studies. This paper will find applications in upcoming frequency sharing and coexistence studies and the design of integrated satellite-terrestrial communication networks.</p>\u0000 </div>","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"42 1","pages":"86-96"},"PeriodicalIF":1.7,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136130082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coexistence of terrestrial and non‐terrestrial networks on adjacent frequency bands","authors":"Lauri Sormunen, Henrik Martikainen, Jani Puttonen, Dorin Panaitopol","doi":"10.1002/sat.1499","DOIUrl":"https://doi.org/10.1002/sat.1499","url":null,"abstract":"Summary This paper presents the latest achievements concerning 3GPP Release‐17 adjacent band coexistence simulation work on 5G new radio non‐terrestrial networks (NTNs) for satellite communications. For the first time, 3GPP considered the introduction of mobile satellite service (MSS) frequency bands for 3GPP user equipment (UE) direct connectivity with satellites and had to consider the coexistence in adjacent bands with terrestrial networks (TNs). This paper will further explain the most challenging and the main surprising outcomes of this work, which opened new market opportunities for both terrestrial and non‐terrestrial stakeholders. The main conclusions can be summarized as follows: (1) NTN UE can reuse the current requirements of the TN UE, (2) the satellite connectivity does not require a dedicated satellite waveform, and (3) TN can co‐exist with NTN on adjacent channels with relaxed ACIR requirements for the tested simulation scenario.","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135690057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of adaptive optics-corrected optical links statistics from integrated turbulence parameters through a Gaussian process metamodel","authors":"Emile Klotz,&nbsp;Sidonie Lefebvre,&nbsp;Nicolas Vedrenne,&nbsp;Christian Musso,&nbsp;Sylvain Poulenard,&nbsp;Thierry Fusco","doi":"10.1002/sat.1497","DOIUrl":"10.1002/sat.1497","url":null,"abstract":"<p>With the development of free space optical links (FSO) for space-ground communications comes the need to mitigate the effects of the atmospheric turbulence to guarantee a lossless connection. By having a network of addressable ground stations, we want to guarantee to always target a point where the link is available. Assuming atmospheric transmission is managed thanks to site diversity, we focus only on the influence of atmospheric turbulence on the signal injected into a single mode fiber on the downlink. The use of adaptive optics (AO) is assumed to avoid turbulence-induced signal disruptions and enable a sufficiently high level of received signal for data transmission. Up to now, AO performance adequate assessment required the knowledge of high-resolution \u0000<math>\u0000 <msubsup>\u0000 <mrow>\u0000 <mi>C</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mi>n</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 </msubsup></math> and wind profiles. With the advent of integrated atmospheric parameters measurement instruments, we investigate here the possibility to estimate AO-corrected performance from a limited number of integrated parameters. In this paper, we propose to use a Gaussian process metamodel to assess the statistics of the received optical power after an AO correction. Taking as input only four integrated parameters of the turbulence profile and associated wind profile, which can be measured with simple instruments, the estimation error on the value of the 1<i>%</i> quantile of the received optical power is inferior to \u0000<math>\u0000 <mn>0</mn>\u0000 <mo>.</mo>\u0000 <mn>7</mn>\u0000 <mtext>dB</mtext></math>. We also demonstrate the possibility to estimate the half correlation time of the received optical power using the same integrated parameters.</p>","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"42 1","pages":"38-56"},"PeriodicalIF":1.7,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/sat.1497","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46344506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Routing in future space-terrestrial integrated networks with SATNET-OSPF","authors":"Hongcheng Yan,&nbsp;Liang Qiao,&nbsp;Wei Wu,&nbsp;Juan A. Fraire,&nbsp;Dong Zhou,&nbsp;Luming Li,&nbsp;Yong Xu","doi":"10.1002/sat.1495","DOIUrl":"10.1002/sat.1495","url":null,"abstract":"<div>\u0000 \u0000 <p>Connectivity in satellite networks is governed by the spacecraft nodes' orbital dynamics together with the planet's continuous rotation where ground nodes are located. The resulting time-dynamic but predictable topology demands the design of specific distributed routing schemes. However, terrestrial Internet routing schemes' maturity, proven scalability, and efficiency shall be leveraged whenever possible to facilitate space-terrestrial integration while reducing risk and costs. In line with this reflection, we introduce SATNET-OSPF: a backward-compatible satellite extension for the widely used Open Shortest Path First routing protocol. The key features of SATNET-OSPF are (a) accurate routing interface mapping to inter-satellite links and ground-to-satellite links, (b) accelerated link-up/link-down event detection adapted to space-specific wireless technologies, (c) proactive routing and forwarding mechanism to take advantage of predicted link-down events, and (d) low memory footprint topology model to efficiently propagate the forthcoming space connectivity events via constrained telecommand links. Leveraging existing IPv6 and OSPFv3 open-source stacks, we implemented SATNET-OSPF in an actual space router comprising a space-grade SPARC V8 CPU and a radiation-hardened FPGA. Furthermore, we present the details of an emulation test bench supporting various configurations with COTS terrestrial OSPF routers that enabled a realistic performance evaluation of the SATNET-OSPF. Results show that SATNET-OSPF reduced OSPFv3 routing protocol overhead by up to 31%; shortened the link event detection delay by four orders of magnitude; decreased the routing outage by a factor of 22; and ensured flooding control message generation and forwarding times, as well as routing computing time, satisfy the original requirements (192, 37, and 17 ms, respectively).</p>\u0000 </div>","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"42 1","pages":"1-25"},"PeriodicalIF":1.7,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42502479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Links assignment scheme based on potential edges importance in dual-layer wavelength routing optical satellite networks","authors":"Jingkai Yang,&nbsp;Qiwen Ran,&nbsp;Hongyu Wu,&nbsp;Jing Ma","doi":"10.1002/sat.1496","DOIUrl":"10.1002/sat.1496","url":null,"abstract":"<div>\u0000 \u0000 <p>With the development of the massive satellite constellation and the on-orbit laser-based communication equipment, wavelength routing optical satellite networks (WROSN) becomes a potential solution for on-orbit, high-capacity, and high-speed communication. Since the inter-satellite links (ISLs) are time-varying, one of the fundamental considerations in the construction of the WROSN is assigning limited laser communication terminals for each satellite to establish ISLs with the visible satellites. Therefore, we propose a links assignment scheme (LAS) based on the potential edges importance matrix (PEIM) algorithm to construct a temporarily stable topology for a dual-layer WROSN (DWROSN). The simulation results showed that the LAS based on the PEIM algorithm diminishes the long-hops route path, reduces the average node-to-node distance, and saves the wavelength demand of the DWROSN. The node pair connectivity and wavelength demand in the DWROSN is a trade-off problem. The research in this paper also brings a novel method for optimizing the route paths and reducing the wavelength demand of wavelength routing optical satellite networks, that is through designing the topology with a links assignment algorithm.</p>\u0000 </div>","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"42 1","pages":"26-37"},"PeriodicalIF":1.7,"publicationDate":"2023-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135182161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Task-oriented resource prediction and adjustment algorithm for space-based information network","authors":"Yufei Wang,&nbsp;Jun Liu,&nbsp;Meili Chen,&nbsp;Sai Xu,&nbsp;Yinnian Hou","doi":"10.1002/sat.1494","DOIUrl":"10.1002/sat.1494","url":null,"abstract":"<div>\u0000 \u0000 <p>The tasks of a space-based information network are complex and diverse, but the resources of a space-based environment are minimal. The existing methods are challenging to match task demand to resource supply accurately. Aiming at the problem of accurate prediction from task to resource, we propose a resource prediction adjustment strategy. First, we propose a multidimensional resource prediction algorithm based on improved particle swarm optimization and back propagation (IPSO-BP) neural network. The improved PSO is used to optimize the weight and threshold of BP neural network to make up for the defects that BP neural network is easy to fall into local minimum and the predicted output value is not unique. Second, to meet the quality of service (QoS) of tasks, we propose a density-based performance evaluation algorithm (DPEA) to adjust resources. This method uses the idea of local sensitive hash to select the evaluation subset for the configuration task, then dynamically selects the \u0000<math>\u0000 <mi>k</mi></math> nearest neighbors of the configuration task, and uses the idea of weighted average to evaluate the QoS performance index of the configuration task. Simulation results show that the proposed resource prediction and adjustment strategy effectively reduces the scheduling time overhead and improves resource utilization.</p>\u0000 </div>","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"41 6","pages":"634-650"},"PeriodicalIF":1.7,"publicationDate":"2023-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42479019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Contribution of non‐orthogonal multiple access signalling to practical multibeam satellite deployments","authors":"T. Ramírez, C. Mosquera","doi":"10.1002/sat.1492","DOIUrl":"https://doi.org/10.1002/sat.1492","url":null,"abstract":"This work explores the contribution of non‐orthogonal multiple access (NOMA) signalling to improve some relevant metrics of a multibeam satellite downlink. Users are paired to exploit signal‐to‐noise ratio (SNR) imbalances coming from the coexistence of different types of terminals, and they can be flexibly allocated to the beams, thus relaxing the cell boundaries of the satellite footprint. Different practical considerations are accommodated, such as a spatially non‐uniform traffic demand, non‐linear amplification effects and the use of the DVB‐S2X air interface. Results show how higher traffic volumes can be channelized by the satellite, thanks to the additional bit rates which are generated for the strong users under the superposition of signals, with carefully designed power levels for DVB‐S2X modulation and coding schemes in the presence of non‐linear impairments.","PeriodicalId":50289,"journal":{"name":"International Journal of Satellite Communications and Networking","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41527470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}