Wireless communications of the next generation rely on large bandwidths and orthogonal frequency division multiple access (OFDMA) techniques to achieve high data rates. In a OFDMA-based wireless wide area network (WWAN), e.g., a cellular network, interference management and handoff are keys to the system performance, such as capacity, coverage, and stability. This paper introduces novel interference management schemes for use in a OFDMA cellular communication system that include dynamic fractional frequency reuse scheme and other cell interference based power control for interference control and avoidance and handoff schemes that employs disjoint links and beacons in a OFDMA cellular communication system.
{"title":"Interference Management and Handoff Techniques in Ultra Mobile Broadband Communication Systems","authors":"M.M. Wang, T. Ji, J. Borran, T. Richardson","doi":"10.1109/ISSSTA.2008.38","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.38","url":null,"abstract":"Wireless communications of the next generation rely on large bandwidths and orthogonal frequency division multiple access (OFDMA) techniques to achieve high data rates. In a OFDMA-based wireless wide area network (WWAN), e.g., a cellular network, interference management and handoff are keys to the system performance, such as capacity, coverage, and stability. This paper introduces novel interference management schemes for use in a OFDMA cellular communication system that include dynamic fractional frequency reuse scheme and other cell interference based power control for interference control and avoidance and handoff schemes that employs disjoint links and beacons in a OFDMA cellular communication system.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125053524","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}
Based on the nature of multi-user multiple-input multiple-output (MIMO) system, a novel downlink grouped-joint transmission (GJT) precoding algorithm is put forward by using grouping technique. In the proposed algorithm, users and their corresponding transmitting signals are partitioned into G groups before been transmitted. Sequentially, the dimensions of channel matrix and other correlative data are reduced, which not affect the performance. Simulation results show that the GJT scheme improve the bit error rate (BER) performance while the complexity of base station (BS) is reduced.
{"title":"A Grouped Precoding in MU-MIMO Downlink","authors":"Yang Shi, Xianwei Xie, Xi Wang","doi":"10.1109/ISSSTA.2008.136","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.136","url":null,"abstract":"Based on the nature of multi-user multiple-input multiple-output (MIMO) system, a novel downlink grouped-joint transmission (GJT) precoding algorithm is put forward by using grouping technique. In the proposed algorithm, users and their corresponding transmitting signals are partitioned into G groups before been transmitted. Sequentially, the dimensions of channel matrix and other correlative data are reduced, which not affect the performance. Simulation results show that the GJT scheme improve the bit error rate (BER) performance while the complexity of base station (BS) is reduced.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"133 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123629756","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}
Efficiently transmitting data in wireless mesh networks requires an integrated routing, scheduling, and power control strategy. Extending previous work on fast distributed routing and power allocation in multi-hop wireless networks we present an algorithmic solution taking the transceiver structure based on interleave-division multiple access and the resulting combinatorial structure of the overall problem explicitly into account. The algorithm offers fast convergence to an optimum solution while providing robust capacity-achieving transmission in each link of a given network.
{"title":"Joint Routing and Power Allocation for IDMA Applied in Multi-Hop Wireless Networks","authors":"H. Schoneich, A. Dekorsy","doi":"10.1109/ISSSTA.2008.113","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.113","url":null,"abstract":"Efficiently transmitting data in wireless mesh networks requires an integrated routing, scheduling, and power control strategy. Extending previous work on fast distributed routing and power allocation in multi-hop wireless networks we present an algorithmic solution taking the transceiver structure based on interleave-division multiple access and the resulting combinatorial structure of the overall problem explicitly into account. The algorithm offers fast convergence to an optimum solution while providing robust capacity-achieving transmission in each link of a given network.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130137898","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 characterize Zigbee networks composed by a set of source nodes which transmit to an access point (AP) either directly or through intermediate relay nodes. In the latter case, both uniform and non-uniform clustering configurations are considered. We evaluate the delay (between transmission and reception of data packets) as a function of the network transmission rate (relative to successful packet transmissions) and tolerable network death level (which will be properly defined). Our results show the existence of a characteristic multidimensional performance surface describing the behavior of a Zigbee network in terms of the three mentioned performance indicators. We heuristically derive a closed-form expression for the network performance surface, by interpolating it through the sum of bidimensional Gaussian surfaces.
{"title":"A Multi-Dimensional Characterization of Clustered Zigbee Networks","authors":"P. Medagliani, M. Martalò, G. Ferrari","doi":"10.1109/ISSSTA.2008.9","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.9","url":null,"abstract":"In this paper, we characterize Zigbee networks composed by a set of source nodes which transmit to an access point (AP) either directly or through intermediate relay nodes. In the latter case, both uniform and non-uniform clustering configurations are considered. We evaluate the delay (between transmission and reception of data packets) as a function of the network transmission rate (relative to successful packet transmissions) and tolerable network death level (which will be properly defined). Our results show the existence of a characteristic multidimensional performance surface describing the behavior of a Zigbee network in terms of the three mentioned performance indicators. We heuristically derive a closed-form expression for the network performance surface, by interpolating it through the sum of bidimensional Gaussian surfaces.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127894990","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}
Cooperation in wireless networks is beneficial for both throughput and power consumption, but requires that nodes are willing to cooperate. As the Nash equilibrium for each node would be a non-cooperative strategy, monitoring nodes' behavior is essential to ensure cooperation. In this paper we present a monitoring approach for networks implementing automatic repeat request (ARQ) and carrier sense multiple access (CSMA). Node misbehavior is detected by listening to all control packets in the network and comparing the packet decoding probability when the monitored node is a destination and when it is a potential cooperator. For this detection strategy, we derive the false alarm and miss detection probabilities, which allow to properly design the system parameters. In order to further improve detection, we propose a distance-based method, where the estimate of the decoding probabilities is improved by enforcing geometric constraints on position of nodes. Both analytical and simulated results are presented for a wireless network characterized by both path-loss and fading.
{"title":"Detection of Selfish Partners by Control Packets in ARQ-Based CSMA Cooperative Networks","authors":"S. Dehnie, Stefano Tomasin","doi":"10.1109/ISSSTA.2008.43","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.43","url":null,"abstract":"Cooperation in wireless networks is beneficial for both throughput and power consumption, but requires that nodes are willing to cooperate. As the Nash equilibrium for each node would be a non-cooperative strategy, monitoring nodes' behavior is essential to ensure cooperation. In this paper we present a monitoring approach for networks implementing automatic repeat request (ARQ) and carrier sense multiple access (CSMA). Node misbehavior is detected by listening to all control packets in the network and comparing the packet decoding probability when the monitored node is a destination and when it is a potential cooperator. For this detection strategy, we derive the false alarm and miss detection probabilities, which allow to properly design the system parameters. In order to further improve detection, we propose a distance-based method, where the estimate of the decoding probabilities is improved by enforcing geometric constraints on position of nodes. Both analytical and simulated results are presented for a wireless network characterized by both path-loss and fading.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124536591","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 report we consider asynchronous spread spectrum multiple access (SSMA) communication systems with spreading sequences of Markov chains. By refinement of the large deviations analysis, we obtain exact asymptotics of bit error probabilities in such systems. Comparing theoretical expressions of bit error probabilities with experimental results, we confirm that for too small number of users compared to the length of spreading sequences, the central limit asymptotics become invalid, but the large deviations asymptotics turn out to be relevant.
{"title":"On Exact Asymptotics of Bit Error Probabilities in SSMA Communication Systems with Spreading Sequences of Markov Chains","authors":"H. Fujisaki","doi":"10.1109/ISSSTA.2008.102","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.102","url":null,"abstract":"In this report we consider asynchronous spread spectrum multiple access (SSMA) communication systems with spreading sequences of Markov chains. By refinement of the large deviations analysis, we obtain exact asymptotics of bit error probabilities in such systems. Comparing theoretical expressions of bit error probabilities with experimental results, we confirm that for too small number of users compared to the length of spreading sequences, the central limit asymptotics become invalid, but the large deviations asymptotics turn out to be relevant.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120978402","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}
Optimum detection for the multiuser code-division multiple-access channel is prohibitively complex. This paper considers new iterative multiuser detection algorithm based on the belief propagation algorithm. Previously, the idea to apply the belief propagation algorithm to multiuser detection problem was suggested , however, it was believed that to apply the belief propagation algorithm to the detection problem is impossible because it requires an exponentially large amount of computation. It was the only fact that the parallel interference canceller is derived as an approximation of the belief propagation. In this paper, we show that the belief propagation algorithm can be applied to the detection problem by converting the factor graph structure. Performance of the detector based on the belief propagation algorithm is better than that of the parallel interference canceller.
{"title":"Multiuser Detection Algorithm for CDMA Based on the Belief Propagation Algorithm","authors":"S. Horii, T. Suko, T. Matsushima, S. Hirasawa","doi":"10.1109/ISSSTA.2008.41","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.41","url":null,"abstract":"Optimum detection for the multiuser code-division multiple-access channel is prohibitively complex. This paper considers new iterative multiuser detection algorithm based on the belief propagation algorithm. Previously, the idea to apply the belief propagation algorithm to multiuser detection problem was suggested , however, it was believed that to apply the belief propagation algorithm to the detection problem is impossible because it requires an exponentially large amount of computation. It was the only fact that the parallel interference canceller is derived as an approximation of the belief propagation. In this paper, we show that the belief propagation algorithm can be applied to the detection problem by converting the factor graph structure. Performance of the detector based on the belief propagation algorithm is better than that of the parallel interference canceller.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"281 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121044529","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 presents the algorithms and the results of multi-user detectors (MUD) on a synchronous chaos-based code division multiple access system (CDMA), which uses chaotic sequences as the spreading codes. Popular linear and non-linear MUD algorithms such as the decorrelator detector, minimum mean square error (MMSE) detector and parallel interference cancellation (PIC) detector are all considered in this paper. These conventional detectors are used to compare the BER performance with a novel blind-MUD receiver. The blind-MUD is achieved by a recently emerged learning technique called support vector machines (SVM). This method can be used to replace the conventional matched filter of the receiver and can be implemented on the forward link. All the MUD schemes are simulated over an AWGN channel and result shows that the blind-MUD compare favorably with other techniques.
{"title":"Blind Multi-User Detection of a Chaos-Based CDMA System Using Support Vector Machine","authors":"J. Kao, S. Berber, V. Kecman","doi":"10.1109/ISSSTA.2008.18","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.18","url":null,"abstract":"This paper presents the algorithms and the results of multi-user detectors (MUD) on a synchronous chaos-based code division multiple access system (CDMA), which uses chaotic sequences as the spreading codes. Popular linear and non-linear MUD algorithms such as the decorrelator detector, minimum mean square error (MMSE) detector and parallel interference cancellation (PIC) detector are all considered in this paper. These conventional detectors are used to compare the BER performance with a novel blind-MUD receiver. The blind-MUD is achieved by a recently emerged learning technique called support vector machines (SVM). This method can be used to replace the conventional matched filter of the receiver and can be implemented on the forward link. All the MUD schemes are simulated over an AWGN channel and result shows that the blind-MUD compare favorably with other techniques.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116203039","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}
S. Rosati, M. Villanti, A. Vanelli-Coralli, G. Corazza
The problem of post-FFT carrier frequency recovery is investigated in the paper proposing a novel approach for both pilot structure and receiver design. In particular, a novel pilot distribution is introduced in order to minimize overlaps between two pattern shifted replicas. This allows to replaces conventional pilots with nulls in the frequency domain, introducing the so called silent pilots. As a result, the optimal receiver turns out to be very robust against severe Rayleigh fading multipath and characterized by low complexity. Performance has been analytically and numerically evaluated, comparing the proposed approach with state of the art alternatives, in both AWGN and multipath fading channels, showing considerable performance improving.
{"title":"OFDM Post-FFT Frequency Recovery Based on Silent Sub-Carriers","authors":"S. Rosati, M. Villanti, A. Vanelli-Coralli, G. Corazza","doi":"10.1109/ISSSTA.2008.90","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.90","url":null,"abstract":"The problem of post-FFT carrier frequency recovery is investigated in the paper proposing a novel approach for both pilot structure and receiver design. In particular, a novel pilot distribution is introduced in order to minimize overlaps between two pattern shifted replicas. This allows to replaces conventional pilots with nulls in the frequency domain, introducing the so called silent pilots. As a result, the optimal receiver turns out to be very robust against severe Rayleigh fading multipath and characterized by low complexity. Performance has been analytically and numerically evaluated, comparing the proposed approach with state of the art alternatives, in both AWGN and multipath fading channels, showing considerable performance improving.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125728688","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 evaluate the maximum uplink user capacity of a macrocell/microcell cellular CDMA system under non-uniform traffic loading conditions. The "hot spots" microcells are embedded within a large macrocell and operate over the same bandwidth as the large cell. The analytic method to compute Erlang user capacity takes into accounts propagation and shadowing losses, arrival process, multiple access interference and power control of user terminals. The necessary desensitivity in the microcell so that it covers only the region of the hot spot is determined. Also, we take into account the soft handoff process and the coverage regions of the microcells for the calculating of the interference in the macrocells and microcells. An analytic expression is obtained for Erlang capacity and for the maximum capacity, which depends of the interference factors and the number of embedded microcells.
{"title":"Analytic Evaluation of the Maximum Uplink Erlang Capacity of a Cellular CDMA System With Macrocells and Embedded Hotspot Microcells","authors":"J.G. Viveros-Talavera, D. Lara-Rodríguez","doi":"10.1109/ISSSTA.2008.23","DOIUrl":"https://doi.org/10.1109/ISSSTA.2008.23","url":null,"abstract":"In this paper, we evaluate the maximum uplink user capacity of a macrocell/microcell cellular CDMA system under non-uniform traffic loading conditions. The \"hot spots\" microcells are embedded within a large macrocell and operate over the same bandwidth as the large cell. The analytic method to compute Erlang user capacity takes into accounts propagation and shadowing losses, arrival process, multiple access interference and power control of user terminals. The necessary desensitivity in the microcell so that it covers only the region of the hot spot is determined. Also, we take into account the soft handoff process and the coverage regions of the microcells for the calculating of the interference in the macrocells and microcells. An analytic expression is obtained for Erlang capacity and for the maximum capacity, which depends of the interference factors and the number of embedded microcells.","PeriodicalId":334589,"journal":{"name":"2008 IEEE 10th International Symposium on Spread Spectrum Techniques and Applications","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128221806","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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