Pub Date : 2006-12-11DOI: 10.1109/PIMRC.2006.254346
R. Kimura, R. Funada, H. Harada, S. Shimamoto
We propose a new multiple-QR-decomposition assisted group detection (multi-QRD-GD) algorithm for the development of reduced-complexity-and-latency multi-input multi-output (MIMO) orthogonal frequency division multiplexing (OFDM) receivers. In addition, we investigate an effect of adaptive grouping (AG) based on received signal-to-noise power ratio for multi-QRD-GD. In this paper, we describe the functions of the multi-QRD-GD algorithm and AG scheme. Then, we compare bit error rate (BER) performances of the proposed multi-QRD-GD and conventional detection algorithms by computer simulations. In addition, we compare the computational complexities of the algorithms
{"title":"Multiple-QR-Decomposition Assisted Group Detection for Reduced-Complexity-and-Latency MIMO-OFDM Receivers","authors":"R. Kimura, R. Funada, H. Harada, S. Shimamoto","doi":"10.1109/PIMRC.2006.254346","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.254346","url":null,"abstract":"We propose a new multiple-QR-decomposition assisted group detection (multi-QRD-GD) algorithm for the development of reduced-complexity-and-latency multi-input multi-output (MIMO) orthogonal frequency division multiplexing (OFDM) receivers. In addition, we investigate an effect of adaptive grouping (AG) based on received signal-to-noise power ratio for multi-QRD-GD. In this paper, we describe the functions of the multi-QRD-GD algorithm and AG scheme. Then, we compare bit error rate (BER) performances of the proposed multi-QRD-GD and conventional detection algorithms by computer simulations. In addition, we compare the computational complexities of the algorithms","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130989306","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.254464
C. Cozzo, Y. Wang
Own-cell interference limits capacity and coverage in the WCDMA enhanced uplink, and the use of interference cancellation (IC) techniques is required to provide high-data-rate availability. For a typical uplink WCDMA system with mixed traffic generated by few high-data-rate users and many low-rate users (e.g., voice users), this paper considers an IC receiver that cancels the high-data-rate signals prior to low-rate traffic reception. The IC receiver provides substantial capacity gains and the benefits of cancellation can be seen as increased achievable data rate for a fixed voice load and/or increased voice load for a target data load. For example, with a data rate of 1.5 Mbps, voice capacity gains are between 60% and 80%. In low voice load, the achievable data rate exceeds 3.5 Mbps. Due to the nature of traffic in WCDMA networks and the option of a short transmission time interval (TTI) for high-data-rate transmission in WCDMA Release 6, this IC scheme is an attractive solution for implementation in base station receivers. In addition, this paper considers also an uplink receiver that cancels the control channels of all users in the cell. Capacity gains are substantial in cells highly loaded with low-rate users
{"title":"Capacity Improvement with Interference Cancellation in the WCDMA Enhanced Uplink","authors":"C. Cozzo, Y. Wang","doi":"10.1109/PIMRC.2006.254464","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.254464","url":null,"abstract":"Own-cell interference limits capacity and coverage in the WCDMA enhanced uplink, and the use of interference cancellation (IC) techniques is required to provide high-data-rate availability. For a typical uplink WCDMA system with mixed traffic generated by few high-data-rate users and many low-rate users (e.g., voice users), this paper considers an IC receiver that cancels the high-data-rate signals prior to low-rate traffic reception. The IC receiver provides substantial capacity gains and the benefits of cancellation can be seen as increased achievable data rate for a fixed voice load and/or increased voice load for a target data load. For example, with a data rate of 1.5 Mbps, voice capacity gains are between 60% and 80%. In low voice load, the achievable data rate exceeds 3.5 Mbps. Due to the nature of traffic in WCDMA networks and the option of a short transmission time interval (TTI) for high-data-rate transmission in WCDMA Release 6, this IC scheme is an attractive solution for implementation in base station receivers. In addition, this paper considers also an uplink receiver that cancels the control channels of all users in the cell. Capacity gains are substantial in cells highly loaded with low-rate users","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131015506","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.253993
P. Pillai, Yim-Fun Hu, A. Lorelli
This paper describes a possible utilization of the UPnP architecture for accounting purposes in moving networks. Starting from a system architecture where the UPnP framework is used for attaching a moving network to a remote network providing a certain number of services, the paper shows how it is possible to use the same UPnP architecture for accounting users in the moving network and for transferring accounting information between a moving network and a remote network (i.e. the service provider); this allows the utilization of the same standard mechanism for all the different signalling purpose
{"title":"Universal Plug and Play Based Billing System for Moving Networks","authors":"P. Pillai, Yim-Fun Hu, A. Lorelli","doi":"10.1109/PIMRC.2006.253993","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.253993","url":null,"abstract":"This paper describes a possible utilization of the UPnP architecture for accounting purposes in moving networks. Starting from a system architecture where the UPnP framework is used for attaching a moving network to a remote network providing a certain number of services, the paper shows how it is possible to use the same UPnP architecture for accounting users in the moving network and for transferring accounting information between a moving network and a remote network (i.e. the service provider); this allows the utilization of the same standard mechanism for all the different signalling purpose","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127881391","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.254362
Hassan El Ghazi, C. Garnier, Y. Delignon
In this paper, we investigate the impact of Walsh-Hadamard spreading code allocation on the performance of a downlink MC-CDMA system in a time varying frequency selective channel. The analysis shows that this impact is important on the multiple access interference and the inter-carrier interference power levels. We propose a code allocation strategy that minimizes the global interference power and significantly improves the performance of the MC-CDMA system
{"title":"Efficient Spreading Code Allocation Strategy for a Downlink MC-CDMA System in a Time Varying Frequency Selective Channel","authors":"Hassan El Ghazi, C. Garnier, Y. Delignon","doi":"10.1109/PIMRC.2006.254362","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.254362","url":null,"abstract":"In this paper, we investigate the impact of Walsh-Hadamard spreading code allocation on the performance of a downlink MC-CDMA system in a time varying frequency selective channel. The analysis shows that this impact is important on the multiple access interference and the inter-carrier interference power levels. We propose a code allocation strategy that minimizes the global interference power and significantly improves the performance of the MC-CDMA system","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125373779","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.254230
Shao-Yi Hung, Po-Yu Chuang, Yi-Hsien Tseng, E. Wu, Gen-Huey Chen
Recently, ultra-wideband (UWB) technologies have attracted considerable attention for its capability, high data rate to achieve 480 Mbps, to wireless personal communications. In this paper, the problem of TCP and energy efficient transmission in IEEE 802.15.3 WPAN based on UWB technologies are addressed. Also, a simple power-efficient scheme for TCP transmission in accordance with IEEE 802.15.3 WPAN standard is proposed and NS2 is used for evaluating the performance of this proposal. The scheme design is driven by two major factors. The first one is that the scheme should provide high TCP throughput in a piconet and low end-to-end delay for TCP packets. The second one is that the scheme should be energy efficient since most mobile devices typically are powered by battery and have limited power capacity. In order to meet these requirements, the energy efficient design at the MAC layer and transport layer is taken into account by the proposed schema
{"title":"Energy Efficient TCP Transmission for IEEE 802.15.3 WPAN","authors":"Shao-Yi Hung, Po-Yu Chuang, Yi-Hsien Tseng, E. Wu, Gen-Huey Chen","doi":"10.1109/PIMRC.2006.254230","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.254230","url":null,"abstract":"Recently, ultra-wideband (UWB) technologies have attracted considerable attention for its capability, high data rate to achieve 480 Mbps, to wireless personal communications. In this paper, the problem of TCP and energy efficient transmission in IEEE 802.15.3 WPAN based on UWB technologies are addressed. Also, a simple power-efficient scheme for TCP transmission in accordance with IEEE 802.15.3 WPAN standard is proposed and NS2 is used for evaluating the performance of this proposal. The scheme design is driven by two major factors. The first one is that the scheme should provide high TCP throughput in a piconet and low end-to-end delay for TCP packets. The second one is that the scheme should be energy efficient since most mobile devices typically are powered by battery and have limited power capacity. In order to meet these requirements, the energy efficient design at the MAC layer and transport layer is taken into account by the proposed schema","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126711890","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.254239
Steve Woon, N. Golmie, Y. Sekercioglu
Effective link layer triggering is the key in order to enable fast and reliable handovers across different access networks. In this paper, we investigate the use of signal strength as part of the trigger mechanism. We propose an analytical model to estimate the anticipation required in order to achieve a target handover packet loss performance, for both voice and video traffic patterns. Numerical results from the analytical model are presented and compared to simulation data obtained for realistic handover scenarios
{"title":"Effective Link Triggers to Improve Handover Performance","authors":"Steve Woon, N. Golmie, Y. Sekercioglu","doi":"10.1109/PIMRC.2006.254239","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.254239","url":null,"abstract":"Effective link layer triggering is the key in order to enable fast and reliable handovers across different access networks. In this paper, we investigate the use of signal strength as part of the trigger mechanism. We propose an analytical model to estimate the anticipation required in order to achieve a target handover packet loss performance, for both voice and video traffic patterns. Numerical results from the analytical model are presented and compared to simulation data obtained for realistic handover scenarios","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126843105","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.253961
Jingon Joung, E. Y. Kim, S. Lim, Yong-Up Jang, Won-Yong Shin, Sae-Young Chung, J. Chun, Y. H. Lee
Presented in this paper is a study of the capacity evaluation of various multiuser MIMO schemes in cellular environments. The throughputs per user of the generalized zero-forcing with rank adaptation and vector perturbation schemes are compared with the capacity bound of the Gaussian MIMO broadcast channel, obtained by dirty paper coding under proportional fairness scheduling. The average cell throughputs of these schemes are also compared. From these comparisons, this study provides vital information for applying multiuser MIMO schemes in multicell environments
{"title":"Capacity Evaluation of Various Multiuser MIMO Schemes in Downlink Cellular Environments","authors":"Jingon Joung, E. Y. Kim, S. Lim, Yong-Up Jang, Won-Yong Shin, Sae-Young Chung, J. Chun, Y. H. Lee","doi":"10.1109/PIMRC.2006.253961","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.253961","url":null,"abstract":"Presented in this paper is a study of the capacity evaluation of various multiuser MIMO schemes in cellular environments. The throughputs per user of the generalized zero-forcing with rank adaptation and vector perturbation schemes are compared with the capacity bound of the Gaussian MIMO broadcast channel, obtained by dirty paper coding under proportional fairness scheduling. The average cell throughputs of these schemes are also compared. From these comparisons, this study provides vital information for applying multiuser MIMO schemes in multicell environments","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123179358","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.254436
T. Tandai, T. Nabetani, K. Toshimitsu, T. Sakamoto
In the next-generation wireless networks, system convergence progressed towards the realization of seamless and ubiquitous environment with software defined radio (SDR). This manuscript proposes a soft-prioritization based system selection algorithm performed by SDR terminal and investigates the effectiveness of the soft-prioritization based system selection by using a concrete simulation model in the practical channel model. To maximize the quality of service (QoS), wireless communication systems are prioritized on the basis of criteria for system selection such as data rate, channel quality and cost, and those systems should be dynamically changed. However, frequent inter-system handovers based on hard-prioritization are undesirable in view of interrupting and dropping communication, particularly for real-time traffics. Wireless communication systems are softly prioritized in the soft-prioritization based system selection algorithm, and therefore inter-system handovers between systems with the same priority aren't initiated. To elucidate the validity of the soft-prioritization based system selection algorithm, a system simulation model consisting of five wireless communication systems is employed. Simulation results confirm that the soft-prioritization system selection algorithm offers higher performance in terms of the number of inter-system handovers and average throughput of best effort traffic
{"title":"Soft-Prioritization Based System Selection Strategy for Software Defined Radio in Heterogeneous Networks","authors":"T. Tandai, T. Nabetani, K. Toshimitsu, T. Sakamoto","doi":"10.1109/PIMRC.2006.254436","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.254436","url":null,"abstract":"In the next-generation wireless networks, system convergence progressed towards the realization of seamless and ubiquitous environment with software defined radio (SDR). This manuscript proposes a soft-prioritization based system selection algorithm performed by SDR terminal and investigates the effectiveness of the soft-prioritization based system selection by using a concrete simulation model in the practical channel model. To maximize the quality of service (QoS), wireless communication systems are prioritized on the basis of criteria for system selection such as data rate, channel quality and cost, and those systems should be dynamically changed. However, frequent inter-system handovers based on hard-prioritization are undesirable in view of interrupting and dropping communication, particularly for real-time traffics. Wireless communication systems are softly prioritized in the soft-prioritization based system selection algorithm, and therefore inter-system handovers between systems with the same priority aren't initiated. To elucidate the validity of the soft-prioritization based system selection algorithm, a system simulation model consisting of five wireless communication systems is employed. Simulation results confirm that the soft-prioritization system selection algorithm offers higher performance in terms of the number of inter-system handovers and average throughput of best effort traffic","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"344 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123314371","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.254290
A. Iera, A. Molinaro, C. Campolo, M. Amadeo
In this paper we present a novel multi-criteria network selection algorithm for always best connected service provisioning. It relies on a suitably defined cost function, which at the same time takes into account metrics reflecting both objective, i.e. network related, and subjective, i.e. user preference related, conditions. Point of strength of our proposal is the implementation of the selection algorithm at a middleware layer; this hiding both network cost computation and 4G scenario complexity from user and application layers. The good performance observed is mainly due to the possibility of associating a weight to each cost parameter that is dynamically adapted to user preferences and profile not only on a per-session basis but also within the same session
{"title":"An Access Network Selection Algorithm Dynamically Adapted to User Needs and Preferences","authors":"A. Iera, A. Molinaro, C. Campolo, M. Amadeo","doi":"10.1109/PIMRC.2006.254290","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.254290","url":null,"abstract":"In this paper we present a novel multi-criteria network selection algorithm for always best connected service provisioning. It relies on a suitably defined cost function, which at the same time takes into account metrics reflecting both objective, i.e. network related, and subjective, i.e. user preference related, conditions. Point of strength of our proposal is the implementation of the selection algorithm at a middleware layer; this hiding both network cost computation and 4G scenario complexity from user and application layers. The good performance observed is mainly due to the possibility of associating a weight to each cost parameter that is dynamically adapted to user preferences and profile not only on a per-session basis but also within the same session","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121614774","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 : 2006-12-11DOI: 10.1109/PIMRC.2006.254384
Markus Myllylä, Pirkka Silvola, M. Juntti, Joseph R. Cavallaro
In this paper, the complexity and performance of two novel list sphere detector (LSD) algorithms are studied and evaluated in multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system. The LSDs are based on the K-best and the Schnorr-Euchner enumeration (SEE) algorithms. The required list sizes for LSD algorithms are determined for a 2times2 system with 4-quadrature amplitude modulation (QAM), 16-QAM, and 64-QAM. The complexity of the algorithms is compared by studying the number of visited nodes per received symbol vector by the algorithm in computer simulations. The SEE based LSD algorithm is found to be a less complex and a feasible choice for implementation compared to the K-best based LSD algorithm
{"title":"Comparison of Two Novel List Sphere Detector Algorithms for MIMO-OFDM Systems","authors":"Markus Myllylä, Pirkka Silvola, M. Juntti, Joseph R. Cavallaro","doi":"10.1109/PIMRC.2006.254384","DOIUrl":"https://doi.org/10.1109/PIMRC.2006.254384","url":null,"abstract":"In this paper, the complexity and performance of two novel list sphere detector (LSD) algorithms are studied and evaluated in multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system. The LSDs are based on the K-best and the Schnorr-Euchner enumeration (SEE) algorithms. The required list sizes for LSD algorithms are determined for a 2times2 system with 4-quadrature amplitude modulation (QAM), 16-QAM, and 64-QAM. The complexity of the algorithms is compared by studying the number of visited nodes per received symbol vector by the algorithm in computer simulations. The SEE based LSD algorithm is found to be a less complex and a feasible choice for implementation compared to the K-best based LSD algorithm","PeriodicalId":325797,"journal":{"name":"2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116087726","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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