It is inevitable for cognitive radio to find unutilized portion of the spectrum more accurately for successful deployment of dynamic spectrum sensing. To achieve highly reliable spectrum sensing, usually cooperative spectrum sensing is employed but still there is a margin to improve local sensing decisions. Cooperative spectrum sensing improves reliability of sensing at the cost of cooperation overhead among cognitive radio users, which can be reduced by improving local spectrum sensing. Several signal processing techniques for primary user detection have been proposed in literature but still there is room for researchers in this field to explore more sophisticated approaches to enhance sensing efficiency. This paper proposes a two stage local spectrum sensing approach. In first step, each cognitive radio perform existing spectrum sensing techniques i.e. energy detection, matched filter detection and cyclostationary detection. While in second stage, the output from each technique employed in step 1 is combined using fuzzy logic to ultimately decide about the presence or absence of primary user. The proposed approach shows significant improvement in sensing accuracy by exhibiting higher probability of detection and low false alarms.
{"title":"Fuzzy Logic Based Spectrum Sensing for Cognitive Radio Networks","authors":"W. Ejaz, N. Hasan, Saleem Aslam, H. Kim","doi":"10.1109/NGMAST.2011.41","DOIUrl":"https://doi.org/10.1109/NGMAST.2011.41","url":null,"abstract":"It is inevitable for cognitive radio to find unutilized portion of the spectrum more accurately for successful deployment of dynamic spectrum sensing. To achieve highly reliable spectrum sensing, usually cooperative spectrum sensing is employed but still there is a margin to improve local sensing decisions. Cooperative spectrum sensing improves reliability of sensing at the cost of cooperation overhead among cognitive radio users, which can be reduced by improving local spectrum sensing. Several signal processing techniques for primary user detection have been proposed in literature but still there is room for researchers in this field to explore more sophisticated approaches to enhance sensing efficiency. This paper proposes a two stage local spectrum sensing approach. In first step, each cognitive radio perform existing spectrum sensing techniques i.e. energy detection, matched filter detection and cyclostationary detection. While in second stage, the output from each technique employed in step 1 is combined using fuzzy logic to ultimately decide about the presence or absence of primary user. The proposed approach shows significant improvement in sensing accuracy by exhibiting higher probability of detection and low false alarms.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124231993","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}
In this paper, a number of spectrum sensing schemes implementation in ultra wideband and Cognitive radio component (UWB-CR) under different fading settings condition are studied. The sensing performance of different detectors is compared in conditions of probability of miss detection curves. Numerically simulation results are shown that the selection of detector rely on the scenario, the detector requirements and on the obtainable prior knowledge. Also simulation results can be shown that it is possible to achieve better detection performance in choosing frequency channel by exploiting the autocorrelation in cyclostationary detection algorithm.
{"title":"Implementation of Spectrum Sensing Methods for UWB-Cognitive Radio System","authors":"Nazar Radhi, Sofian Hamad, H. Al-Raweshidy","doi":"10.1109/NGMAST.2011.34","DOIUrl":"https://doi.org/10.1109/NGMAST.2011.34","url":null,"abstract":"In this paper, a number of spectrum sensing schemes implementation in ultra wideband and Cognitive radio component (UWB-CR) under different fading settings condition are studied. The sensing performance of different detectors is compared in conditions of probability of miss detection curves. Numerically simulation results are shown that the selection of detector rely on the scenario, the detector requirements and on the obtainable prior knowledge. Also simulation results can be shown that it is possible to achieve better detection performance in choosing frequency channel by exploiting the autocorrelation in cyclostationary detection algorithm.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122274328","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}
In communication technology, cognitive radio networks can be effectively used to detect and track targets of interested (primary users). Primary transmitter location through the collaborative effort of multiple cognitive radio nodes is relevant in this investigate. A two stage source localization process is proposed in this work, the time difference of arrival values (TDOA) are first determined using the generalize cross correlation (GCC) method and then TDOA values are used by a least squares (LS) estimation scheme to determine the primary transmitter location. The effect number of CR nodes, spacing of inter node, topology, noise, distance of source to node, node failure, location perturbation on the location estimation performance have been studied through MATLAB simulation. Simulation result illustrate that the error difference can be reduced by increasing the number of CR nodes or the spacing inter nodes and improve the location estimation accuracy. The CR node topology should be well represented in all three dimensions to obtain required location estimation performance. In additional, result show that the primary transmitter location estimation accuracy is not harmfully affected by CR node failures or location perturbations.
{"title":"Primary Signal Transmitter Localization Using Cognitive Radio Networks","authors":"Nazar Radhi, H. Al-Raweshidy","doi":"10.1109/NGMAST.2011.33","DOIUrl":"https://doi.org/10.1109/NGMAST.2011.33","url":null,"abstract":"In communication technology, cognitive radio networks can be effectively used to detect and track targets of interested (primary users). Primary transmitter location through the collaborative effort of multiple cognitive radio nodes is relevant in this investigate. A two stage source localization process is proposed in this work, the time difference of arrival values (TDOA) are first determined using the generalize cross correlation (GCC) method and then TDOA values are used by a least squares (LS) estimation scheme to determine the primary transmitter location. The effect number of CR nodes, spacing of inter node, topology, noise, distance of source to node, node failure, location perturbation on the location estimation performance have been studied through MATLAB simulation. Simulation result illustrate that the error difference can be reduced by increasing the number of CR nodes or the spacing inter nodes and improve the location estimation accuracy. The CR node topology should be well represented in all three dimensions to obtain required location estimation performance. In additional, result show that the primary transmitter location estimation accuracy is not harmfully affected by CR node failures or location perturbations.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126557054","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}
In a user-centric approach, the user wants to have a unique and continuous service session that best answers his ambient context. Spatial mobility is one of the factors that cause modifications in this ambient context and consequently influence the user's service session. On the network layers, many solutions have been conceived to overcome this challenge. However, this problem is not yet investigated on the service layer. For this purpose, we propose in this paper the concept of semantic handover. This concept acts on the service layer by analogy to the network's handover mechanisms. It is based on three complementary roles: the initiator, that detects a variation in user's ambient context caused by spatial mobility and that initiates the semantic handover, the decider, that decides which services should be replaced in user's service session and what are their ubiquitous counterparts, and the executor, that executes the decision and adapts user's service session to the new ambient context. By using this novel concept, we guarantee a seamless continuous service session for the end-user throughout his spatial mobility and ambient context. User's functional and non-functional (QoS criteria) preferences are also taken into account through the usage of the ubiquity approach in this service session adaptation.
{"title":"Semantic Handover for Seamless Service Continuity within User Ambient Context","authors":"R. Nassar, Soumia Kessal, N. Simoni","doi":"10.1109/NGMAST.2011.17","DOIUrl":"https://doi.org/10.1109/NGMAST.2011.17","url":null,"abstract":"In a user-centric approach, the user wants to have a unique and continuous service session that best answers his ambient context. Spatial mobility is one of the factors that cause modifications in this ambient context and consequently influence the user's service session. On the network layers, many solutions have been conceived to overcome this challenge. However, this problem is not yet investigated on the service layer. For this purpose, we propose in this paper the concept of semantic handover. This concept acts on the service layer by analogy to the network's handover mechanisms. It is based on three complementary roles: the initiator, that detects a variation in user's ambient context caused by spatial mobility and that initiates the semantic handover, the decider, that decides which services should be replaced in user's service session and what are their ubiquitous counterparts, and the executor, that executes the decision and adapts user's service session to the new ambient context. By using this novel concept, we guarantee a seamless continuous service session for the end-user throughout his spatial mobility and ambient context. User's functional and non-functional (QoS criteria) preferences are also taken into account through the usage of the ubiquity approach in this service session adaptation.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117250521","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}
A. V. Nieuwenhuyse, L. D. Strycker, N. Stevens, Jean-Pierre Goemaere, B. Nauwelaers
Increasing importance of localizing objects in indoor environments is the motivation for many research on localization algorithms. This paper focuses on the maximum achievable resolution for Angle of Arrival as a means to position objects inside rooms using equipment within the field of wireless sensor networks, thus dealing with restricted resources. A clear view on beam forming using antenna arrays is represented and is proven to be useful in Angle of Arrival measurements. The choice of the linear antenna array as most appropriate solution is motivated. A detailed overview of the algorithm, used to calculate the maximum realistic resolution, leads us to draw conclusions concerning the resolution. Depending on the number of anchor nodes and the composition of the antenna arrays, a reference value can be defined to calculate the realistic resolution for all room dimensions.
{"title":"Analysis of the Realistic Resolution with Angle of Arrival for Indoor Positioning","authors":"A. V. Nieuwenhuyse, L. D. Strycker, N. Stevens, Jean-Pierre Goemaere, B. Nauwelaers","doi":"10.4018/jhcr.2013040101","DOIUrl":"https://doi.org/10.4018/jhcr.2013040101","url":null,"abstract":"Increasing importance of localizing objects in indoor environments is the motivation for many research on localization algorithms. This paper focuses on the maximum achievable resolution for Angle of Arrival as a means to position objects inside rooms using equipment within the field of wireless sensor networks, thus dealing with restricted resources. A clear view on beam forming using antenna arrays is represented and is proven to be useful in Angle of Arrival measurements. The choice of the linear antenna array as most appropriate solution is motivated. A detailed overview of the algorithm, used to calculate the maximum realistic resolution, leads us to draw conclusions concerning the resolution. Depending on the number of anchor nodes and the composition of the antenna arrays, a reference value can be defined to calculate the realistic resolution for all room dimensions.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"427 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132387403","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}
In this paper we experiment with multi-display mobile applications that can be used in an environment where multiple smart phones are co-located within the same space. Utilizing Remote User Interface techniques and the REST architectural style we propose a solution that follows the Remote Model-View-Controller model, in such a way that client devices do not need to have application specific software pre-installed. We demonstrate the system with the Panorama Bricks application, for displaying, in a multi-display expanded view, street-view style mirror-world panoramas, in a synchronized manner. The architecture proves that such enhanced application scenarios are possible to implement even today, utilizing off-the-shelf mobile smart phones.
{"title":"Experiences Building a Multi-Display Mobile Application for Exploring Mirror Worlds","authors":"Vlad Stirbu, P. Belimpasakis","doi":"10.1109/NGMAST.2011.11","DOIUrl":"https://doi.org/10.1109/NGMAST.2011.11","url":null,"abstract":"In this paper we experiment with multi-display mobile applications that can be used in an environment where multiple smart phones are co-located within the same space. Utilizing Remote User Interface techniques and the REST architectural style we propose a solution that follows the Remote Model-View-Controller model, in such a way that client devices do not need to have application specific software pre-installed. We demonstrate the system with the Panorama Bricks application, for displaying, in a multi-display expanded view, street-view style mirror-world panoramas, in a synchronized manner. The architecture proves that such enhanced application scenarios are possible to implement even today, utilizing off-the-shelf mobile smart phones.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131862570","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}
Nowadays different sectors such as transport companies or public safety and emergency forces have great demand in mobile communications. In general, this area raises complex scenarios, where different access networks can be used, based on high-level administrative parameters (cost, geographic location). The use of different access networks could bring advantages in terms of availability and quality of service. In this paper the use of a node with Network Mobility (NEMO) Basic Support and enhanced capabilities for processing and executing high-level rules is proposed. This rule-based approach allows intelligent routing according to different parameters such as cost, geographical position, etc. The use of this node will facilitate the deployment of improved communication scenarios where there are complex requirements regarding the different access networks available at the time, switching between them according to administrative policies.
{"title":"A Rule-based Approach in Network Mobility IP Routing","authors":"J. Navarro, M. Cao, M. Álvarez-Campana, R. Romero","doi":"10.1109/NGMAST.2011.35","DOIUrl":"https://doi.org/10.1109/NGMAST.2011.35","url":null,"abstract":"Nowadays different sectors such as transport companies or public safety and emergency forces have great demand in mobile communications. In general, this area raises complex scenarios, where different access networks can be used, based on high-level administrative parameters (cost, geographic location). The use of different access networks could bring advantages in terms of availability and quality of service. In this paper the use of a node with Network Mobility (NEMO) Basic Support and enhanced capabilities for processing and executing high-level rules is proposed. This rule-based approach allows intelligent routing according to different parameters such as cost, geographical position, etc. The use of this node will facilitate the deployment of improved communication scenarios where there are complex requirements regarding the different access networks available at the time, switching between them according to administrative policies.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127135647","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}
Most existing location-based services rely on ubiquitous connectivity to deliver location-based contents to the users. However, connectivity is not available anywhere at anytime even in urban centres. Underground, indoors, remote areas, and foreign countries are examples situations where users commonly do not have guaranteed connectivity but could profit from location-based contents. In this work, we propose an open platform for publishing, distributing and maintaining location-based contents that can be accessed offline by the user on a mobile device. Additionally, we describe the prototype we implemented for proof of concept consisting of an smart phone application and a web application back office, using 2D-barcodes as location identifiers. Our prototype provides offline access, as well as publishing, installing and updating location-based content.
{"title":"OLBS: Offline Location Based Services","authors":"Pedro Coelho, Ana Aguiar, J. C. Lopes","doi":"10.1109/NGMAST.2011.22","DOIUrl":"https://doi.org/10.1109/NGMAST.2011.22","url":null,"abstract":"Most existing location-based services rely on ubiquitous connectivity to deliver location-based contents to the users. However, connectivity is not available anywhere at anytime even in urban centres. Underground, indoors, remote areas, and foreign countries are examples situations where users commonly do not have guaranteed connectivity but could profit from location-based contents. In this work, we propose an open platform for publishing, distributing and maintaining location-based contents that can be accessed offline by the user on a mobile device. Additionally, we describe the prototype we implemented for proof of concept consisting of an smart phone application and a web application back office, using 2D-barcodes as location identifiers. Our prototype provides offline access, as well as publishing, installing and updating location-based content.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126238435","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}
This document presents the development of an extension to the SMS Service for Android smart phones, which adds audio and visual characteristics to this widely used communication service. With this solution, when a SMS message is received, it is read by a 3D avatar, who performs the liparticulatory movements and the emotional facial expressions synchronized with the audio corresponding to the content of the message.
{"title":"Expressive Audiovisual Message Presenter for Mobile Devices","authors":"A. G. Goncalves, J. M. D. Martino","doi":"10.4018/jhcr.2013010105","DOIUrl":"https://doi.org/10.4018/jhcr.2013010105","url":null,"abstract":"This document presents the development of an extension to the SMS Service for Android smart phones, which adds audio and visual characteristics to this widely used communication service. With this solution, when a SMS message is received, it is read by a 3D avatar, who performs the liparticulatory movements and the emotional facial expressions synchronized with the audio corresponding to the content of the message.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128028941","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}
Mobile end user context has gained increasing attention in the mobile services industry. Context information is seen as an important component in developing new, more personalized, mobile services and applications. This paper studies the effect of end user context on smart phone usage sessions. Smart phone usage sessions are used to depict user behavior and usage habits of smart phone users on a high level. We have detected end user contexts, and extracted smart phone usage session information from handset-based data of 140 smart phone users. We first examine and describe usage sessions as such, and then in different end user contexts. According to our usage session analysis, smart phone usage is highly diversified across users. For example, the average number of sessions per day ranges from 3 to 46. Characteristics of smart phone usage sessions differ in different end user contexts. For example, an average session is 37 % longer in the Home-context than in the Office-context, but Office has 56 % more sessions per time unit than Home. The results imply that mobile services and applications need to adapt to user behavior in order to be personalized enough, and that context awareness is indeed a worthwhile step towards this.
{"title":"Diversity and End User Context in Smartphone Usage Sessions","authors":"Tapio Soikkeli, Juuso Karikoski, H. Hämmäinen","doi":"10.1109/NGMAST.2011.12","DOIUrl":"https://doi.org/10.1109/NGMAST.2011.12","url":null,"abstract":"Mobile end user context has gained increasing attention in the mobile services industry. Context information is seen as an important component in developing new, more personalized, mobile services and applications. This paper studies the effect of end user context on smart phone usage sessions. Smart phone usage sessions are used to depict user behavior and usage habits of smart phone users on a high level. We have detected end user contexts, and extracted smart phone usage session information from handset-based data of 140 smart phone users. We first examine and describe usage sessions as such, and then in different end user contexts. According to our usage session analysis, smart phone usage is highly diversified across users. For example, the average number of sessions per day ranges from 3 to 46. Characteristics of smart phone usage sessions differ in different end user contexts. For example, an average session is 37 % longer in the Home-context than in the Office-context, but Office has 56 % more sessions per time unit than Home. The results imply that mobile services and applications need to adapt to user behavior in order to be personalized enough, and that context awareness is indeed a worthwhile step towards this.","PeriodicalId":142071,"journal":{"name":"2011 Fifth International Conference on Next Generation Mobile Applications, Services and Technologies","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121853098","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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