Pub Date : 2012-03-27DOI: 10.1049/iet-com.2011.0105
F. Nadeem, E. Leitgeb, G. Kandus, T. Javornik
The huge bandwidth of optical Wireless link motivates to use it for high data rate demanding communication applications. However, an appreciable high availability of the link is the basic requirement of any communication link. Free Space Optics (FSO) links are highly weather dependent. One of the important attenuating factors is snow that causes reduced the link availability. The use of back up link can provide the solution. Hybrid networks of Free Space Optics (FSO) link and back up link in the GHz frequency range improves the availability besides providing comparable data rates. The back up link should be nearly immune to different attenuation factors including snow for achieving carrier class availability. In this paper effects of dry snow on FSO and GHz frequency range links are studied so that frequencies with best complementary behaviour can be selected as a back up link. The specific attenuation of different FSO lengths has also been analysed using measured results.
{"title":"Comparing the snow effects on hybrid network using optical Wireless and GHz links","authors":"F. Nadeem, E. Leitgeb, G. Kandus, T. Javornik","doi":"10.1049/iet-com.2011.0105","DOIUrl":"https://doi.org/10.1049/iet-com.2011.0105","url":null,"abstract":"The huge bandwidth of optical Wireless link motivates to use it for high data rate demanding communication applications. However, an appreciable high availability of the link is the basic requirement of any communication link. Free Space Optics (FSO) links are highly weather dependent. One of the important attenuating factors is snow that causes reduced the link availability. The use of back up link can provide the solution. Hybrid networks of Free Space Optics (FSO) link and back up link in the GHz frequency range improves the availability besides providing comparable data rates. The back up link should be nearly immune to different attenuation factors including snow for achieving carrier class availability. In this paper effects of dry snow on FSO and GHz frequency range links are studied so that frequencies with best complementary behaviour can be selected as a back up link. The specific attenuation of different FSO lengths has also been analysed using measured results.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128134808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1109/GLOCOM.2010.5683427
L. Liang, H. Cruickshank, Zhili Sun, C. Kulatunga, G. Fairhurst
Multicast research has explored the security challenges faced in group communications. Multicast transport and multicast security need to work in close collaboration to realise a multicast service. However, there has been comparatively little work to combine the two technologies. In this paper the authors is presenting an example of partially integrating Timed Efficient Stream Loss-Tolerant Authentication (TESLA) protocol and the File Delivery over Unidirectional Transport (FLUTE) protocol. The security concern raised by the proposed algorithm is analysed for satellite network. The proposed algorithm was implemented on a testbed with multicast tunnel between University of Surrey and University of Aberdeen and the results are presented in this paper.
{"title":"Integration of TESLA and FLUTE over satellite networks","authors":"L. Liang, H. Cruickshank, Zhili Sun, C. Kulatunga, G. Fairhurst","doi":"10.1109/GLOCOM.2010.5683427","DOIUrl":"https://doi.org/10.1109/GLOCOM.2010.5683427","url":null,"abstract":"Multicast research has explored the security challenges faced in group communications. Multicast transport and multicast security need to work in close collaboration to realise a multicast service. However, there has been comparatively little work to combine the two technologies. In this paper the authors is presenting an example of partially integrating Timed Efficient Stream Loss-Tolerant Authentication (TESLA) protocol and the File Delivery over Unidirectional Transport (FLUTE) protocol. The security concern raised by the proposed algorithm is analysed for satellite network. The proposed algorithm was implemented on a testbed with multicast tunnel between University of Surrey and University of Aberdeen and the results are presented in this paper.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131766692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286345
H. Cruickshank
{"title":"Regular session 5 (room 4) delay tolerant networking","authors":"H. Cruickshank","doi":"10.1109/IWSSC.2009.5286345","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286345","url":null,"abstract":"","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116772327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286339
N. Bhutta, Godwin Ansa, Enyenihi Johnson, Naveed Ahmad, M. Al-Siyabi, H. Cruickshank
In the last few years, Delay/Disruption Tolerant Networking has grown to a healthy research topic because of its suitability for challenged environments characterized by heterogeneity, long delay paths and unpredictable link disruptions. This paper presents a DTN security architecture that focuses on the requirements for lightweight key management; lightweight AAA-like architecture for authentication/authorisation; resilience to Denial of Service attacks and user anonymity.
{"title":"Security analysis for Delay/Disruption Tolerant satellite and sensor networks","authors":"N. Bhutta, Godwin Ansa, Enyenihi Johnson, Naveed Ahmad, M. Al-Siyabi, H. Cruickshank","doi":"10.1109/IWSSC.2009.5286339","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286339","url":null,"abstract":"In the last few years, Delay/Disruption Tolerant Networking has grown to a healthy research topic because of its suitability for challenged environments characterized by heterogeneity, long delay paths and unpredictable link disruptions. This paper presents a DTN security architecture that focuses on the requirements for lightweight key management; lightweight AAA-like architecture for authentication/authorisation; resilience to Denial of Service attacks and user anonymity.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122857809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286390
E. Duca, C. Facchinetti, M. Cosmo
Optical technology and navigation techniques can successfully enhance space communication segment. The wide bandwidth offered by optics and advanced multiplation techniques, may increase the available capacity of the space communication channel. Pointing and tracking are critical procedures to keep the link established when the spot size has a reduced area as in case of optical wavelength. The enhancement brought by navigation techniques relies on higher accuracy on positioning of spacecraft, in particular when it comes to Geostationary satellites positioning for whom high precision in positioning maybe a constraint, given the huge distances. Thus, navigation techniques can make the pointing procedure faster and enlarge the effective operative window. A critical scenario where this interoperability becomes fundamental is based on a cluster of formation flying satellites for Earth Observation Missions. Real time connectivity may be provided by inter-satellite links. Aim of this paper is to point out the key features of the proposed scenario, where the interoperability between communications and navigation techniques provides a solution to enhance Earth Observation Missions.
{"title":"Navigation techniques enhancing inter-satellite communication for Earth Observation Missions","authors":"E. Duca, C. Facchinetti, M. Cosmo","doi":"10.1109/IWSSC.2009.5286390","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286390","url":null,"abstract":"Optical technology and navigation techniques can successfully enhance space communication segment. The wide bandwidth offered by optics and advanced multiplation techniques, may increase the available capacity of the space communication channel. Pointing and tracking are critical procedures to keep the link established when the spot size has a reduced area as in case of optical wavelength. The enhancement brought by navigation techniques relies on higher accuracy on positioning of spacecraft, in particular when it comes to Geostationary satellites positioning for whom high precision in positioning maybe a constraint, given the huge distances. Thus, navigation techniques can make the pointing procedure faster and enlarge the effective operative window. A critical scenario where this interoperability becomes fundamental is based on a cluster of formation flying satellites for Earth Observation Missions. Real time connectivity may be provided by inter-satellite links. Aim of this paper is to point out the key features of the proposed scenario, where the interoperability between communications and navigation techniques provides a solution to enhance Earth Observation Missions.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129734959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286365
F. Nadeem, E. Leitgeb, M. S. Awan, G. Kandus
Free space Optic (FSO) links have the tremendous potential to fulfil high data rate requirements of future communication applications. However, the widespread growth of FSO has been hampered by availability and reliability issues. FSO links are highly weather dependent and attenuating factor like fog, rain and snow causes reduced link availability for considerable amount of time. However different optical wavelengths suffer different attenuation. In this paper, the attenuation of different wavelengths FSO links has been analysed under different weather attenuating condition like fog, rain and snow. The attenuation analysis has been compared using measured attenuation data for some of the wavelengths.
{"title":"Optical wavelengths comparison for different weather conditions","authors":"F. Nadeem, E. Leitgeb, M. S. Awan, G. Kandus","doi":"10.1109/IWSSC.2009.5286365","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286365","url":null,"abstract":"Free space Optic (FSO) links have the tremendous potential to fulfil high data rate requirements of future communication applications. However, the widespread growth of FSO has been hampered by availability and reliability issues. FSO links are highly weather dependent and attenuating factor like fog, rain and snow causes reduced link availability for considerable amount of time. However different optical wavelengths suffer different attenuation. In this paper, the attenuation of different wavelengths FSO links has been analysed under different weather attenuating condition like fog, rain and snow. The attenuation analysis has been compared using measured attenuation data for some of the wavelengths.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"294 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132459689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286396
S. Pino-Povedano, F. González-Serrano
This paper tries to reduce the Peak-to-Average Power Ratio (PAPR) of Orthogonal Frequency Division Multiplexing (OFDM) signal using a method that combines the use of Convex Optimization and Amplitude Predistortion. To reduce the peak of the OFDM signal, the proposed method applies one of the techniques on free carriers and the other one on the data carriers. Depending on the method used in each carrier, two different variants of it can be identify. Throughout this article, it is demonstrated that a significant improvement of ht performance can be obtained with a combination of the two methods with a slight increase in the computational complexity.
{"title":"PAPR reduction for OFDM transmission using a method of Convex Optimization and Amplitude Predistortion","authors":"S. Pino-Povedano, F. González-Serrano","doi":"10.1109/IWSSC.2009.5286396","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286396","url":null,"abstract":"This paper tries to reduce the Peak-to-Average Power Ratio (PAPR) of Orthogonal Frequency Division Multiplexing (OFDM) signal using a method that combines the use of Convex Optimization and Amplitude Predistortion. To reduce the peak of the OFDM signal, the proposed method applies one of the techniques on free carriers and the other one on the data carriers. Depending on the method used in each carrier, two different variants of it can be identify. Throughout this article, it is demonstrated that a significant improvement of ht performance can be obtained with a combination of the two methods with a slight increase in the computational complexity.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129391910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286391
B. Preindl, L. Mehnen, F. Rattay, J. Nielsen
Small satellites gain more and more interests from both educational and academic institutions, but also from the industry. They constitute a cheap alternative to large, more expensive and more complex satellites. A consequence of their small form factor is the lack of space for secondary payload, like advanced communication facilities. These deficiencies make it difficult to apply quality assurances concerning satellite communication links on the ground segment. Previous approaches have been primarily passive and focused only on the bit error rate of receiving links at ground stations. The results therefor covered only one direction of a bidirectional link and even if they were quite accurate in common, they were nevertheless only approximations. In this paper a novel design solution based on a small satellite cluster is going to be proposed to offer quality assurance for the ground segment in both sending and receiving directions in multiple amateur frequency bands based on highaccurate error rate information.
{"title":"Design of a small satellite for performing measurements in a ground station network","authors":"B. Preindl, L. Mehnen, F. Rattay, J. Nielsen","doi":"10.1109/IWSSC.2009.5286391","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286391","url":null,"abstract":"Small satellites gain more and more interests from both educational and academic institutions, but also from the industry. They constitute a cheap alternative to large, more expensive and more complex satellites. A consequence of their small form factor is the lack of space for secondary payload, like advanced communication facilities. These deficiencies make it difficult to apply quality assurances concerning satellite communication links on the ground segment. Previous approaches have been primarily passive and focused only on the bit error rate of receiving links at ground stations. The results therefor covered only one direction of a bidirectional link and even if they were quite accurate in common, they were nevertheless only approximations. In this paper a novel design solution based on a small satellite cluster is going to be proposed to offer quality assurance for the ground segment in both sending and receiving directions in multiple amateur frequency bands based on highaccurate error rate information.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130894561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286324
M. Luglio, C. Roseti, G. Savone, F. Zampognaro
High-speed rail is emerging in the world as an increasingly popular and efficient means of transportation used by a lot of people, who may also need a broadband Internet connection while travelling for their business and leisure. Satellite systems for their intrinsic characteristic, such as global coverage, reduced impact of Doppler effect due to link geometry and flexible bandwidth management, represent an excellent solution to provide broadband services in the identified scenario. Some problems specific of the railway propagation channel such as frequent signal outages due to the periodic electrical trellises, tunnels and steel covered bridges affect TCP/IP performance due to frequent packet losses occurring in bursts. In this paper, performance of TCP-based applications and error recovery mechanisms are investigated and the use of a new transport protocol named TCP-Noordwijk is introduced. TCP-Noordwijk leverages on a burst transmission and is particularly suited for the harsh satellite links. Results show that TCP-Noordwijk outperforms the other analyzed TCP versions.
{"title":"TCP performance on a railway satellite channel","authors":"M. Luglio, C. Roseti, G. Savone, F. Zampognaro","doi":"10.1109/IWSSC.2009.5286324","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286324","url":null,"abstract":"High-speed rail is emerging in the world as an increasingly popular and efficient means of transportation used by a lot of people, who may also need a broadband Internet connection while travelling for their business and leisure. Satellite systems for their intrinsic characteristic, such as global coverage, reduced impact of Doppler effect due to link geometry and flexible bandwidth management, represent an excellent solution to provide broadband services in the identified scenario. Some problems specific of the railway propagation channel such as frequent signal outages due to the periodic electrical trellises, tunnels and steel covered bridges affect TCP/IP performance due to frequent packet losses occurring in bursts. In this paper, performance of TCP-based applications and error recovery mechanisms are investigated and the use of a new transport protocol named TCP-Noordwijk is introduced. TCP-Noordwijk leverages on a burst transmission and is particularly suited for the harsh satellite links. Results show that TCP-Noordwijk outperforms the other analyzed TCP versions.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132877973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-10-13DOI: 10.1109/IWSSC.2009.5286386
H. Cerezo-Costas, R. Asorey-Cacheda, F. González-Castaño
In this paper, we present a bandwidth limited and error tolerant near-Video-on-Demand (nVoD) schema suitable for satellite networks. Compared to traditional nVoD schemas, such as carousels, it outperforms in terms of download start letency and packet loss tolerance. Video-on Demand (VoD) has been a topic of intense research in the past. The main problem of VoD systems is that their bandwidth requirements do not scale well with user requests. For this reason, VoD is only feasible under some constraints. In general, nVoD systems are an approximation of VoD ones. In them, downloads do not necessarily start when the request arrives, but some time later. by doing so, it is possible to bound the total required bandwidth at the cost of introducing some delay in content download.
{"title":"A bandwidth limited and error tolerant nVoD schema for satellite networks","authors":"H. Cerezo-Costas, R. Asorey-Cacheda, F. González-Castaño","doi":"10.1109/IWSSC.2009.5286386","DOIUrl":"https://doi.org/10.1109/IWSSC.2009.5286386","url":null,"abstract":"In this paper, we present a bandwidth limited and error tolerant near-Video-on-Demand (nVoD) schema suitable for satellite networks. Compared to traditional nVoD schemas, such as carousels, it outperforms in terms of download start letency and packet loss tolerance. Video-on Demand (VoD) has been a topic of intense research in the past. The main problem of VoD systems is that their bandwidth requirements do not scale well with user requests. For this reason, VoD is only feasible under some constraints. In general, nVoD systems are an approximation of VoD ones. In them, downloads do not necessarily start when the request arrives, but some time later. by doing so, it is possible to bound the total required bandwidth at the cost of introducing some delay in content download.","PeriodicalId":137431,"journal":{"name":"2009 International Workshop on Satellite and Space Communications","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132570588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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