Pub Date : 2009-03-30DOI: 10.1109/SARNOF.2009.4850298
B. Maham, A. Hjørungnes
Due to the limited energy supplies of nodes, in many applications like wireless sensor networks, energy-efficiency is crucial for extending the lifetime of these networks. We study the routing problem for multihop wireless ad hoc networks based on cooperative transmission. The source node wants to transmit messages to a single destination. Other nodes in the network may operate as relay nodes. In this paper, we propose a cooperative multihop routing for the purpose of power savings, constrained on a required outage probability at the destination. We derive two efficient power allocation schemes, which only depend on the statistics of the channels. It is shown that energy savings of 90% are achievable in line networks with 10 relays for 10−4 outage probability constraint at each receiving node.
{"title":"Minimum power allocation for cooperative routing in multihop wireless networks","authors":"B. Maham, A. Hjørungnes","doi":"10.1109/SARNOF.2009.4850298","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850298","url":null,"abstract":"Due to the limited energy supplies of nodes, in many applications like wireless sensor networks, energy-efficiency is crucial for extending the lifetime of these networks. We study the routing problem for multihop wireless ad hoc networks based on cooperative transmission. The source node wants to transmit messages to a single destination. Other nodes in the network may operate as relay nodes. In this paper, we propose a cooperative multihop routing for the purpose of power savings, constrained on a required outage probability at the destination. We derive two efficient power allocation schemes, which only depend on the statistics of the channels. It is shown that energy savings of 90% are achievable in line networks with 10 relays for 10−4 outage probability constraint at each receiving node.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134236857","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850345
S. Xi, M. Zoltowski
The Lloyd's vector quantization method is adopted to design a codebook for multiuser transmit beamforming vectors over multiple-input multiple-output (MIMO) channels which only allow limited feedback. The beamformer code-book is designed to maximize the post-processing signal-to-interference-plus-noise ratio (SINR), and the resulting codebook is called maximum SINR (MSINR) codebook. The MSINR cooperative beamforming algorithm proposed in our previous work under the assumption that the instant channel information of all users is perfectly known to each user as well as the receiver is modified to obtain the code for a given set of channel samples, which is the key step in the Lloyd's method. The obtained codebook, as revealed by the numerical results, is robust to a wide range of deviation of the actual transmit SNR from that associated with a codebook.
{"title":"Maximum SINR transmit beamforming for multiuser MIMO systems with limited feedback","authors":"S. Xi, M. Zoltowski","doi":"10.1109/SARNOF.2009.4850345","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850345","url":null,"abstract":"The Lloyd's vector quantization method is adopted to design a codebook for multiuser transmit beamforming vectors over multiple-input multiple-output (MIMO) channels which only allow limited feedback. The beamformer code-book is designed to maximize the post-processing signal-to-interference-plus-noise ratio (SINR), and the resulting codebook is called maximum SINR (MSINR) codebook. The MSINR cooperative beamforming algorithm proposed in our previous work under the assumption that the instant channel information of all users is perfectly known to each user as well as the receiver is modified to obtain the code for a given set of channel samples, which is the key step in the Lloyd's method. The obtained codebook, as revealed by the numerical results, is robust to a wide range of deviation of the actual transmit SNR from that associated with a codebook.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"213 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133232601","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850381
D. Sterne, G. Lawler
MANETs lack natural concentration points at which a single dedicated node can monitor all network traffic for intrusions. Consequently, detecting attacks on MANETs requires distributed, cooperative intrusion detection techniques. We examine an approach to organizing a cooperative intrusion detection system for MANETs as a dynamic hierarchy that adapts to changes in topology and other environmental factors. We describe the rationale for this approach, the design of a set of hierarchy services to support it, and our experience developing prototype intrusion detection components that utilize these services.
{"title":"A dynamic intrusion detection hierarchy for MANETs","authors":"D. Sterne, G. Lawler","doi":"10.1109/SARNOF.2009.4850381","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850381","url":null,"abstract":"MANETs lack natural concentration points at which a single dedicated node can monitor all network traffic for intrusions. Consequently, detecting attacks on MANETs requires distributed, cooperative intrusion detection techniques. We examine an approach to organizing a cooperative intrusion detection system for MANETs as a dynamic hierarchy that adapts to changes in topology and other environmental factors. We describe the rationale for this approach, the design of a set of hierarchy services to support it, and our experience developing prototype intrusion detection components that utilize these services.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114971545","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850334
I. Lu
A novel unified approach to deal with arbitrary transmitted power constraints for designing jointly the MMSE precoders and decoders in downlink multiuser MIMO systems is developed. This work is an extension of the iterative approach developed in [1] for the total power constraint. An explicit expression relating Lagrange multipliers with the per-user constraint can be obtained using the proposed approach to mitigate the time consuming root searching for the Lagrange multipliers in [1]. Moreover, the explicit expression allows the MMSE solution subject to arbitrary transmit power constraints. In this paper, total, per-user, per-antenna, and peak power constraints are formulated in under the same format and solved using the proposed approach. It is shown in some two-user numerical examples that the raw BER performance obtained from the practical per-antenna power constraint is similar to those of the per-user and total power constraints and is 1–1.5 dB better than that of the peak power constraint.
{"title":"Joint MMSE precoder and decoder design for downlink multiuser MIMO systems with arbitrary transmit power constraints","authors":"I. Lu","doi":"10.1109/SARNOF.2009.4850334","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850334","url":null,"abstract":"A novel unified approach to deal with arbitrary transmitted power constraints for designing jointly the MMSE precoders and decoders in downlink multiuser MIMO systems is developed. This work is an extension of the iterative approach developed in [1] for the total power constraint. An explicit expression relating Lagrange multipliers with the per-user constraint can be obtained using the proposed approach to mitigate the time consuming root searching for the Lagrange multipliers in [1]. Moreover, the explicit expression allows the MMSE solution subject to arbitrary transmit power constraints. In this paper, total, per-user, per-antenna, and peak power constraints are formulated in under the same format and solved using the proposed approach. It is shown in some two-user numerical examples that the raw BER performance obtained from the practical per-antenna power constraint is similar to those of the per-user and total power constraints and is 1–1.5 dB better than that of the peak power constraint.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115742649","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850382
Paul L. Yu, J. Baras, Brian M. Sadler
Physical layer authentication techniques exploit signal characteristics to identify radios. We describe how multicarrier systems may use such techniques to stealthily authenticate while maintaining high levels of security and robustness. We show that with channel state information (CSI) at the transmitter and receiver, multicarrier authentication systems can further improve performance by carefully allocating the authentication power on each carrier
{"title":"Power allocation tradeoffs in multicarrier authentication systems","authors":"Paul L. Yu, J. Baras, Brian M. Sadler","doi":"10.1109/SARNOF.2009.4850382","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850382","url":null,"abstract":"Physical layer authentication techniques exploit signal characteristics to identify radios. We describe how multicarrier systems may use such techniques to stealthily authenticate while maintaining high levels of security and robustness. We show that with channel state information (CSI) at the transmitter and receiver, multicarrier authentication systems can further improve performance by carefully allocating the authentication power on each carrier","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"216 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122388331","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850278
Gami Hiren, M. Qasaymeh, N. Tayem, R. Pendse, M. E. Sawan
Orthogonal Frequency Division Multiplexing (OFDM) is a promising technique to handle impairments of multipath channel. Alternatively, one of its major drawbacks is the drift in reference carrier, which is known as Carrier Frequency Offset (CFO). Hence, the CFO should be estimated and compensated with a sufficient accuracy. In this paper, a new algorithm for blind CFO-OFDM estimation is obtained by introducing the Propagator Method (PM) in conjunction with the well-known MUSIC based high resolution searching algorithm. Furthermore, the PM does not require the Eigenvalue Decomposition (EVD) or Singular Value Decomposition (SVD) of the covariance matrix of the received signals; Simulations are also included to demonstrate the effectiveness of the proposed method in comparison with other conventional methods.
{"title":"Subspace based blind CFO estimation for OFDM by exploiting used carriers","authors":"Gami Hiren, M. Qasaymeh, N. Tayem, R. Pendse, M. E. Sawan","doi":"10.1109/SARNOF.2009.4850278","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850278","url":null,"abstract":"Orthogonal Frequency Division Multiplexing (OFDM) is a promising technique to handle impairments of multipath channel. Alternatively, one of its major drawbacks is the drift in reference carrier, which is known as Carrier Frequency Offset (CFO). Hence, the CFO should be estimated and compensated with a sufficient accuracy. In this paper, a new algorithm for blind CFO-OFDM estimation is obtained by introducing the Propagator Method (PM) in conjunction with the well-known MUSIC based high resolution searching algorithm. Furthermore, the PM does not require the Eigenvalue Decomposition (EVD) or Singular Value Decomposition (SVD) of the covariance matrix of the received signals; Simulations are also included to demonstrate the effectiveness of the proposed method in comparison with other conventional methods.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125995669","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850350
G. Auer, S. Videv, Birendra Ghimire, H. Haas
A distributed reservation protocol tailored for cellular wireless networks is presented that facilitates contention free inter-cellular slot allocation and reservation. While reserved slots are protected from inter-cell interference by a busy burst enabled reservation protocol, collisions due to simultaneously accessed unreserved slots by neighboring cells are mitigated by means of resource partitioning patterns. Cyclically shifting these partitioning patterns in time allows each cell to successively probe all slots within a fixed time interval. This establishes an intercellular slot contention policy that dynamically controls the initial spatial reuse, in terms of concurrently accessed radio resources by neighboring cells. Despite the controlled spatial reuse of resource during contention, the possibility of a cell to use all available radio resources, if the load and interference situation permits, remains unaffected. As a consequence, loss in spectrum efficiency as observed in frequency-planned cellular systems is avoided.
{"title":"Contention free dynamic slot allocation in cellular networks","authors":"G. Auer, S. Videv, Birendra Ghimire, H. Haas","doi":"10.1109/SARNOF.2009.4850350","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850350","url":null,"abstract":"A distributed reservation protocol tailored for cellular wireless networks is presented that facilitates contention free inter-cellular slot allocation and reservation. While reserved slots are protected from inter-cell interference by a busy burst enabled reservation protocol, collisions due to simultaneously accessed unreserved slots by neighboring cells are mitigated by means of resource partitioning patterns. Cyclically shifting these partitioning patterns in time allows each cell to successively probe all slots within a fixed time interval. This establishes an intercellular slot contention policy that dynamically controls the initial spatial reuse, in terms of concurrently accessed radio resources by neighboring cells. Despite the controlled spatial reuse of resource during contention, the possibility of a cell to use all available radio resources, if the load and interference situation permits, remains unaffected. As a consequence, loss in spectrum efficiency as observed in frequency-planned cellular systems is avoided.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117119206","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850342
Mohamed Elalem, Lian Zhao
WCDMA is becoming widely accepted as one of the most promising solutions to meet the increasing demand for high-capacity wireless networks of the future. The most important inherent characteristic of WCDMA systems is their interference-limited capacity. The user distribution is a very important issue. In most previous studies it is assumed that the spatial distribution of the users is uniform within the cell. This paper presents a study of the effect of a selected user distribution on the performance of a WCDMA cellular system. A more realistic user distribution is chosen with specific parameters and a new interference distribution factor is developed as a function of these parameters. The capacity and coverage are compared for the uniform and nonuniform user distributions.
{"title":"Realistic user distribution and its impact on capacity and coverage for a WCDMA mobile network","authors":"Mohamed Elalem, Lian Zhao","doi":"10.1109/SARNOF.2009.4850342","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850342","url":null,"abstract":"WCDMA is becoming widely accepted as one of the most promising solutions to meet the increasing demand for high-capacity wireless networks of the future. The most important inherent characteristic of WCDMA systems is their interference-limited capacity. The user distribution is a very important issue. In most previous studies it is assumed that the spatial distribution of the users is uniform within the cell. This paper presents a study of the effect of a selected user distribution on the performance of a WCDMA cellular system. A more realistic user distribution is chosen with specific parameters and a new interference distribution factor is developed as a function of these parameters. The capacity and coverage are compared for the uniform and nonuniform user distributions.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127020320","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850338
L. Sofman, B. Krogfoss, A. Agrawal
In an IPTV network, a large amount of unicast traffic from the Video Head Office (VHO) to subscribers requires significant BW and equipment resources in the network. Caching of video content allows reduction of bandwidth and IPTV network cost. In this paper, we consider a caching architecture in which part of the content is cached at the edge of the network (e.g., at DSLAMs), and the remaining part is stored in server(s) at the VHO. We assume that the community of subscribers subtended at each cache location (DSLAM) may have unique interests. Therefore, the list of cached items is customized for each cache location (e.g., individual DSLAM), and different cache locations should store different content. We consider U-turn caching where titles cached at a given DSLAM may serve the requests of subscribers that are subtended not only at this DSLAM but also from those subtended at neighboring DSLAMs. We discuss how the U-turn caching architecture allows increased cache effectiveness (hit rate) by sharing cache resources in the access nodes (DSLAMs).
{"title":"U-turn caching optimization in IPTV networks","authors":"L. Sofman, B. Krogfoss, A. Agrawal","doi":"10.1109/SARNOF.2009.4850338","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850338","url":null,"abstract":"In an IPTV network, a large amount of unicast traffic from the Video Head Office (VHO) to subscribers requires significant BW and equipment resources in the network. Caching of video content allows reduction of bandwidth and IPTV network cost. In this paper, we consider a caching architecture in which part of the content is cached at the edge of the network (e.g., at DSLAMs), and the remaining part is stored in server(s) at the VHO. We assume that the community of subscribers subtended at each cache location (DSLAM) may have unique interests. Therefore, the list of cached items is customized for each cache location (e.g., individual DSLAM), and different cache locations should store different content. We consider U-turn caching where titles cached at a given DSLAM may serve the requests of subscribers that are subtended not only at this DSLAM but also from those subtended at neighboring DSLAMs. We discuss how the U-turn caching architecture allows increased cache effectiveness (hit rate) by sharing cache resources in the access nodes (DSLAMs).","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125511033","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850284
Gideon S. K. Yong, C. Saavedra
A novel quadrature generator is presented in this paper that exhibits a 40% operating frequency bandwidth. Current circuits do not generally provide quadrature signals over such a wide fractional bandwidth and they are often susceptible to variances in component values, which can shift their operating frequency. In this work, this is resolved with the use of a negative feedback network including a pair of phase shifters and two variable gain amplifiers to actively compensate the imbalances over a large frequency range. Experimental results show a 2GHz bandwidth centered at 5 GHz while maintaining a phase error below 8° and less than 1.5 dB in amplitude error. The circuit, without bonding pads, uses an area of only 0.28mm2.
{"title":"A wideband feedback compensated quadrature generator","authors":"Gideon S. K. Yong, C. Saavedra","doi":"10.1109/SARNOF.2009.4850284","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850284","url":null,"abstract":"A novel quadrature generator is presented in this paper that exhibits a 40% operating frequency bandwidth. Current circuits do not generally provide quadrature signals over such a wide fractional bandwidth and they are often susceptible to variances in component values, which can shift their operating frequency. In this work, this is resolved with the use of a negative feedback network including a pair of phase shifters and two variable gain amplifiers to actively compensate the imbalances over a large frequency range. Experimental results show a 2GHz bandwidth centered at 5 GHz while maintaining a phase error below 8° and less than 1.5 dB in amplitude error. The circuit, without bonding pads, uses an area of only 0.28mm2.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131202824","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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