J. Thriveni, B. Ashwini, A. Latha, K. R. Sandhyashree, G. Prakash, K. Venugopal, L. Patnaik
Broadcasting in Ad hoc networks is prone to broadcast storm problem and ACK implosion problem. These problems create the necessity to carefully designate some nodes in the 1-hop neighborhood of sender as forwarding nodes and reduce broadcast redundancy. In this paper, we have proposed an algorithm called enhanced double covered broadcast with negative acknowledgements (EDCBN) which focuses on achieving high delivery ratio in an environment that has high transmission error rate. We make use of negative acknowledgements to achieve better reliability. Overhead caused due to acknowledgements are avoided by allowing the sender to overhear the retransmissions from the receiver. Simulation results show that EDCBN algorithm improves the reliability of broadcast operation compared to double covered broadcast (DCB) and use less number of forwarding nodes to forward the packet in sparse network.
{"title":"Broadcast with negative acknowledgements for enhanced delivery ratio in MANET with dual coverage","authors":"J. Thriveni, B. Ashwini, A. Latha, K. R. Sandhyashree, G. Prakash, K. Venugopal, L. Patnaik","doi":"10.1109/WD.2008.4812858","DOIUrl":"https://doi.org/10.1109/WD.2008.4812858","url":null,"abstract":"Broadcasting in Ad hoc networks is prone to broadcast storm problem and ACK implosion problem. These problems create the necessity to carefully designate some nodes in the 1-hop neighborhood of sender as forwarding nodes and reduce broadcast redundancy. In this paper, we have proposed an algorithm called enhanced double covered broadcast with negative acknowledgements (EDCBN) which focuses on achieving high delivery ratio in an environment that has high transmission error rate. We make use of negative acknowledgements to achieve better reliability. Overhead caused due to acknowledgements are avoided by allowing the sender to overhear the retransmissions from the receiver. Simulation results show that EDCBN algorithm improves the reliability of broadcast operation compared to double covered broadcast (DCB) and use less number of forwarding nodes to forward the packet in sparse network.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"87 11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131220575","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}
Multiple Description Coding (MDC) is a method to solve the problem of noisy channels affecting images. Multiple descriptions (multiple copies) of images are transmitted over different channels while at the receiver; the images are reconstructed using the different copies. In this paper, five MDC methods are proposed and discussed, while results shown their improvement in images quality.
{"title":"Multiple description image transmission over unreliable channel","authors":"Ali M. Dawood, Ahmed Ali Al Shal, R. Hamila","doi":"10.1109/WD.2008.4812875","DOIUrl":"https://doi.org/10.1109/WD.2008.4812875","url":null,"abstract":"Multiple Description Coding (MDC) is a method to solve the problem of noisy channels affecting images. Multiple descriptions (multiple copies) of images are transmitted over different channels while at the receiver; the images are reconstructed using the different copies. In this paper, five MDC methods are proposed and discussed, while results shown their improvement in images quality.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129128841","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 consider a blind source separation problem in which the number of sources is unknown and all or some of the sources may be networks with frequency hopping spread spectrum capability. We should first find the number of sources and then fairly track each of the detected networks. The extracted information of detected sources are used to update an internal model in the cognitive radio that helps it to predict and avoid frequencies in which active FHSS radios in the environment are simultaneously transmitting. In the proposed method, there is no need to have several antennas for DOA estimation and this will significantly reduce implementation cost and complexity of the algorithm. Due to real time nature of the problem, the simple structure of this method in comparison with other existing algorithms will make it preferable. We propose a method based on a probabilistic classifier to separate detected networks in sequential frames. The efficiency of the proposed method is demonstrated by simulation results.
{"title":"Blind source separation and tracking of multiple frequency hopping signals for cognitive radio communications","authors":"M. Mohammadi, Mohammad M. Taheri","doi":"10.1109/WD.2008.4812868","DOIUrl":"https://doi.org/10.1109/WD.2008.4812868","url":null,"abstract":"In this paper we consider a blind source separation problem in which the number of sources is unknown and all or some of the sources may be networks with frequency hopping spread spectrum capability. We should first find the number of sources and then fairly track each of the detected networks. The extracted information of detected sources are used to update an internal model in the cognitive radio that helps it to predict and avoid frequencies in which active FHSS radios in the environment are simultaneously transmitting. In the proposed method, there is no need to have several antennas for DOA estimation and this will significantly reduce implementation cost and complexity of the algorithm. Due to real time nature of the problem, the simple structure of this method in comparison with other existing algorithms will make it preferable. We propose a method based on a probabilistic classifier to separate detected networks in sequential frames. The efficiency of the proposed method is demonstrated by simulation results.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125939454","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 the last few years the scientific community has shown a growing interest regarding infrastructures for vehicular ad hoc networks (VANETs) communication as a special application of the more generic mobile ad hoc networks (MANETs). Adoption of a public transportation network as a VANET backbone - thanks to the full area coverage and a pre-scheduled repetitive path - can be an interesting solution in many situations where sensor networks are too expensive or does not scale well. In this paper we will discuss performances of routing protocols when applied to public transportation VANETs. We argue that, in this specific case, especially if a many-to-one communication paradigm is in place, routing strategies commonly adopted in VANETs can be a less appealing solution when compared to simpler ones, like distance vector algorithms. Through extensive simulations we demonstrate that, in the considered network scenario, a simple distance vector-based routing algorithm performs well. As a result, more complex - and resource hungry - protocols are no longer strictly needed.
{"title":"Performance evaluation of distance vector-based routing protocols for public transportation vehicular networks","authors":"F. Giudici, D. Maggiorini, G. P. Rossi","doi":"10.1109/WD.2008.4812923","DOIUrl":"https://doi.org/10.1109/WD.2008.4812923","url":null,"abstract":"In the last few years the scientific community has shown a growing interest regarding infrastructures for vehicular ad hoc networks (VANETs) communication as a special application of the more generic mobile ad hoc networks (MANETs). Adoption of a public transportation network as a VANET backbone - thanks to the full area coverage and a pre-scheduled repetitive path - can be an interesting solution in many situations where sensor networks are too expensive or does not scale well. In this paper we will discuss performances of routing protocols when applied to public transportation VANETs. We argue that, in this specific case, especially if a many-to-one communication paradigm is in place, routing strategies commonly adopted in VANETs can be a less appealing solution when compared to simpler ones, like distance vector algorithms. Through extensive simulations we demonstrate that, in the considered network scenario, a simple distance vector-based routing algorithm performs well. As a result, more complex - and resource hungry - protocols are no longer strictly needed.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125155852","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 new approach of continuous phase QPSK Band-Pass modulation technique is being developed as enhancement to the QPSK modulation scheme for inductive data transmission (NFC). The modulation is based on Gaussian filtering of the phase transition from one state to the other rather than discontinuity in phase shift. The carrier is based on low frequency 115 KHz suitable for human body energy penetration due to its large skin-depth and lower inductive power attenuation. The complete signal processing is done digitally, external coil and capacitor is used for transceiver interface. The telemetry assists a smart pill swallowed by human being to trigger an actuator for drug delivery, record temperature, or perform diagnostic task inside the body. The smart pill includes 32bit processor, 16 Kbyte memory, temperature sensor, telemetry unit, and additional external peripheries. The complete system is designed, embedded in one SoC, and realized on ASIC with chip-area less than 14 mm2.
{"title":"Enhanced telemetry system using CP-QPSK Band-Pass modulation technique suitable for smart pill medical application","authors":"N. Fawaz, D. Jansen","doi":"10.1109/WD.2008.4812855","DOIUrl":"https://doi.org/10.1109/WD.2008.4812855","url":null,"abstract":"A new approach of continuous phase QPSK Band-Pass modulation technique is being developed as enhancement to the QPSK modulation scheme for inductive data transmission (NFC). The modulation is based on Gaussian filtering of the phase transition from one state to the other rather than discontinuity in phase shift. The carrier is based on low frequency 115 KHz suitable for human body energy penetration due to its large skin-depth and lower inductive power attenuation. The complete signal processing is done digitally, external coil and capacitor is used for transceiver interface. The telemetry assists a smart pill swallowed by human being to trigger an actuator for drug delivery, record temperature, or perform diagnostic task inside the body. The smart pill includes 32bit processor, 16 Kbyte memory, temperature sensor, telemetry unit, and additional external peripheries. The complete system is designed, embedded in one SoC, and realized on ASIC with chip-area less than 14 mm2.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121749746","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}
Anelise Munaretto, R. Souza, M. Fonseca, Ricardo Borges
This paper investigates the use of MIMO techniques in a multihop wireless network. We consider that the link between any two nodes can be established using one of two different MIMO schemes and one of many modulation orders. Computer simulations were carried out in order to identify the best configuration for different channel conditions. Then, the source-to-destination route, which may be composed of multiple hops, is optimized in order to maximize the data throughput. Simulation results indicate that the adaptive selection of the MIMO technique and the modulation order for each link can considerably increase the data throughput in a multihop network.
{"title":"Using MIMO adaptive transmission for increasing the throughput of a multihop wireless network","authors":"Anelise Munaretto, R. Souza, M. Fonseca, Ricardo Borges","doi":"10.1109/WD.2008.4812837","DOIUrl":"https://doi.org/10.1109/WD.2008.4812837","url":null,"abstract":"This paper investigates the use of MIMO techniques in a multihop wireless network. We consider that the link between any two nodes can be established using one of two different MIMO schemes and one of many modulation orders. Computer simulations were carried out in order to identify the best configuration for different channel conditions. Then, the source-to-destination route, which may be composed of multiple hops, is optimized in order to maximize the data throughput. Simulation results indicate that the adaptive selection of the MIMO technique and the modulation order for each link can considerably increase the data throughput in a multihop network.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125017394","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}
Voice over Wireless LAN (VoWLAN) is becoming more and more helpful in our life and is expected to be among the most important applications in next generation networks. However, the maximum number of VoIP sessions that a WLAN can ensure is very small. Moreover, when the WLAN reaches its capacity the addition of one VoIP session affects the QoS parameters of all VoIP sessions. In this paper, we propose an adaptive technique to ensure the active VoIP sessions of users with high priority (from a provider perspective). Thus, in order to guarantee the quality of high priority sessions, we propose to downgrade the quality (low but acceptable MOS) of user sessions with low priority by changing their used codecs (e.g., ITU G729 instead of ITU G711). This technique and all related monitoring functions are defined into the proposed session-based QoS management architecture. In order to validate our approach a complete test-bed is made up by which we have performed some feasibility and gain tests.
{"title":"Codec-based adaptive QoS control for VoWLAN with differentiated services","authors":"Badis Tebbani, K. Haddadou","doi":"10.1109/WD.2008.4812886","DOIUrl":"https://doi.org/10.1109/WD.2008.4812886","url":null,"abstract":"Voice over Wireless LAN (VoWLAN) is becoming more and more helpful in our life and is expected to be among the most important applications in next generation networks. However, the maximum number of VoIP sessions that a WLAN can ensure is very small. Moreover, when the WLAN reaches its capacity the addition of one VoIP session affects the QoS parameters of all VoIP sessions. In this paper, we propose an adaptive technique to ensure the active VoIP sessions of users with high priority (from a provider perspective). Thus, in order to guarantee the quality of high priority sessions, we propose to downgrade the quality (low but acceptable MOS) of user sessions with low priority by changing their used codecs (e.g., ITU G729 instead of ITU G711). This technique and all related monitoring functions are defined into the proposed session-based QoS management architecture. In order to validate our approach a complete test-bed is made up by which we have performed some feasibility and gain tests.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131909230","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}
RFID is an automatic identification technology that enables tracking of people and objects. Both identity and location are generally key information for indoor services. An obvious and interesting method to obtain these two types of data is to localize RFID tags attached to devices or objects or carried by people. However, signals in indoor environments are generally harshly impaired and tags have very limited capabilities which pose many challenges for positioning them. In this work, we propose a classification and survey the current state-of-art of RFID localization by first presenting this technology and positioning principles. Then, we explain and classify RFID localization techniques. Finally, we discuss future trends in this domain.
{"title":"RFID tags: Positioning principles and localization techniques","authors":"M. Bouet, A. Santos","doi":"10.1109/WD.2008.4812905","DOIUrl":"https://doi.org/10.1109/WD.2008.4812905","url":null,"abstract":"RFID is an automatic identification technology that enables tracking of people and objects. Both identity and location are generally key information for indoor services. An obvious and interesting method to obtain these two types of data is to localize RFID tags attached to devices or objects or carried by people. However, signals in indoor environments are generally harshly impaired and tags have very limited capabilities which pose many challenges for positioning them. In this work, we propose a classification and survey the current state-of-art of RFID localization by first presenting this technology and positioning principles. Then, we explain and classify RFID localization techniques. Finally, we discuss future trends in this domain.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131159285","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}
Antti Alasalmi, O. Martikainen, Tomohiro Kuroda, T. Takemura, Naoto Kume, Hiroyuki Yoshihara, Tsuyoshi Nagashima, Naoki Oboshi
The research by Maliranta and Rouvinen based on the Finnish industrial statistics confirms that the productivity improvements in firms correlate to organizational and process changes (Maliranta and Rouvinen, 2003 and Maliranta and Rouvinen, 2004). These results implied a further question: Which types of process changes create the most beneficial productivity improvements in different environments. This question should be of major importance when new services are applied or developed. The research on process improvements has been done in ETLA and in the University of Oulu, where the Three Viewpoint Methodology (3VPM) (Martikainen, 2007) was developed for productivity analysis. In this paper we apply the 3VPM methodology to analyze the nursing documentation process and the impact of documentation process improvement by wireless services on core nursing process in Kyoto University Hospital. The information was collected by interviews and server logs. We have analyzed the benefit of introducing wireless PDA (Personal Digital Assistant) devices to update patient data on place instead of writing it down by hand and later storing it into the system on PC (Personal Computer) and consider other possible solutions like sensors, wireless tracking and touch by device paradigm. Nursing documentation process can be clearly improved and the improvement of the nursing process can be as much as 14%. This means that the same patient intensity can be achieved with less number of nurses.
{"title":"Core nursing process improvement enabled by wireless services","authors":"Antti Alasalmi, O. Martikainen, Tomohiro Kuroda, T. Takemura, Naoto Kume, Hiroyuki Yoshihara, Tsuyoshi Nagashima, Naoki Oboshi","doi":"10.1109/WD.2008.4812829","DOIUrl":"https://doi.org/10.1109/WD.2008.4812829","url":null,"abstract":"The research by Maliranta and Rouvinen based on the Finnish industrial statistics confirms that the productivity improvements in firms correlate to organizational and process changes (Maliranta and Rouvinen, 2003 and Maliranta and Rouvinen, 2004). These results implied a further question: Which types of process changes create the most beneficial productivity improvements in different environments. This question should be of major importance when new services are applied or developed. The research on process improvements has been done in ETLA and in the University of Oulu, where the Three Viewpoint Methodology (3VPM) (Martikainen, 2007) was developed for productivity analysis. In this paper we apply the 3VPM methodology to analyze the nursing documentation process and the impact of documentation process improvement by wireless services on core nursing process in Kyoto University Hospital. The information was collected by interviews and server logs. We have analyzed the benefit of introducing wireless PDA (Personal Digital Assistant) devices to update patient data on place instead of writing it down by hand and later storing it into the system on PC (Personal Computer) and consider other possible solutions like sensors, wireless tracking and touch by device paradigm. Nursing documentation process can be clearly improved and the improvement of the nursing process can be as much as 14%. This means that the same patient intensity can be achieved with less number of nurses.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133838427","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 paper addresses the issue of wireless bandwidth partitioning of a mobile WiMAX cell. We consider a complete partitioning strategy, where the wireless bandwidth capacity of a cell is divided into trunks. Each partition is strictly reserved to a particular type of connection. Precisely, we distinguish four IEEE 802.16e 2005 service classes: UGS, rtPS, nrtPS and ErtPS. As we consider mobility, we also differentiate new call request from handoff ones. In addition, we take into consideration the adaptive modulation and coding (AMC) scheme, through the partition of the cell into different areas associated to a particular modulation and coding scheme. The purpose of the paper is to determine, using an analytical model and a heuristic approach, the nearly-optimal sizes of the partition sizes dedicated to each type of connection, which is characterized by 1) its service class, 2) type of request and 3) modulation and coding scheme. The main concern here is to propose simple and robust computational methods, which can be easily and efficiently used to dimension a mobile WiMAX network.
{"title":"Bandwidth partitioning for Mobile WiMAX service provisioning","authors":"Sondes Khemiri, K. Boussetta, N. Achir","doi":"10.1109/WD.2008.4812926","DOIUrl":"https://doi.org/10.1109/WD.2008.4812926","url":null,"abstract":"This paper addresses the issue of wireless bandwidth partitioning of a mobile WiMAX cell. We consider a complete partitioning strategy, where the wireless bandwidth capacity of a cell is divided into trunks. Each partition is strictly reserved to a particular type of connection. Precisely, we distinguish four IEEE 802.16e 2005 service classes: UGS, rtPS, nrtPS and ErtPS. As we consider mobility, we also differentiate new call request from handoff ones. In addition, we take into consideration the adaptive modulation and coding (AMC) scheme, through the partition of the cell into different areas associated to a particular modulation and coding scheme. The purpose of the paper is to determine, using an analytical model and a heuristic approach, the nearly-optimal sizes of the partition sizes dedicated to each type of connection, which is characterized by 1) its service class, 2) type of request and 3) modulation and coding scheme. The main concern here is to propose simple and robust computational methods, which can be easily and efficiently used to dimension a mobile WiMAX network.","PeriodicalId":247938,"journal":{"name":"2008 1st IFIP Wireless Days","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132660071","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：