Pub Date : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258657
S. Kaiser
The paper investigates different diversity concepts for OFDM systems. These are space frequency block codes (SFBCs) and code division multiplexing (CDM). The performances of both, and of combinations of both, are compared for coded OFDM systems in a Rayleigh fading channel. The applied SFBCs and CDM have in common that they have no rate loss and thus do not decrease the bandwidth efficiency of the system. While the SFBCs exploit space and frequency diversity, CDM exploits frequency and time diversity in OFDM systems. Additionally, the effects due to diversity gains by channel coding are taken into account in the investigations.
{"title":"Space frequency block codes and code division multiplexing in OFDM systems","authors":"S. Kaiser","doi":"10.1109/GLOCOM.2003.1258657","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258657","url":null,"abstract":"The paper investigates different diversity concepts for OFDM systems. These are space frequency block codes (SFBCs) and code division multiplexing (CDM). The performances of both, and of combinations of both, are compared for coded OFDM systems in a Rayleigh fading channel. The applied SFBCs and CDM have in common that they have no rate loss and thus do not decrease the bandwidth efficiency of the system. While the SFBCs exploit space and frequency diversity, CDM exploits frequency and time diversity in OFDM systems. Additionally, the effects due to diversity gains by channel coding are taken into account in the investigations.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"280 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125772122","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258724
Lihong Yang, Yuming Jiang, Shengming Jiang
In this paper, we propose a probabilistic preemptive (PP) scheme for service differentiation in optical burst switching (OBS) networks. By changing the preemptive probability, an OBS node can adjust the ratio of burst blocking probability between different traffic classes, while the overall blocking probability is not affected.
{"title":"A probabilistic preemptive scheme for providing service differentiation in OBS networks","authors":"Lihong Yang, Yuming Jiang, Shengming Jiang","doi":"10.1109/GLOCOM.2003.1258724","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258724","url":null,"abstract":"In this paper, we propose a probabilistic preemptive (PP) scheme for service differentiation in optical burst switching (OBS) networks. By changing the preemptive probability, an OBS node can adjust the ratio of burst blocking probability between different traffic classes, while the overall blocking probability is not affected.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121978492","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1259006
J. Qaddour, Daniel Leonard, M. Matalgah, M. Guizani
OFDM has emerged as a potential option for the delivery of broadband wireless. Since its development for military applications in the 1960s, technical implementations of OFDM have appeared in digital audio broadcasting, digital subscriber lines, high definition television terrestrial broadcasting, and other systems. The paper presents an estimation of the uplink capacity for OFDM using test wireless cellular environment simulations. Spread-spectrum signals are employed. The objective is to obtain the uplink performance for data oriented services using this intriguing new delivery system.
{"title":"Beyond 3G: uplink capacity estimation for wireless spread-spectrum orthogonal frequency division multiplexing (SS-OFDM)","authors":"J. Qaddour, Daniel Leonard, M. Matalgah, M. Guizani","doi":"10.1109/GLOCOM.2003.1259006","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1259006","url":null,"abstract":"OFDM has emerged as a potential option for the delivery of broadband wireless. Since its development for military applications in the 1960s, technical implementations of OFDM have appeared in digital audio broadcasting, digital subscriber lines, high definition television terrestrial broadcasting, and other systems. The paper presents an estimation of the uplink capacity for OFDM using test wireless cellular environment simulations. Spread-spectrum signals are employed. The objective is to obtain the uplink performance for data oriented services using this intriguing new delivery system.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122268370","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258644
Yu-Yi Cheng, Yumin Lee, Hsueh-Jyh Li
A receiver algorithm for OFDM with receiver diversity is proposed. The proposed receiver uses a new two-step blind channel estimation algorithm referred to as the subspace-MMSE channel estimator. Minimum mean square error linear diversity combining is then performed based on the estimated channel. Simulation results show that performance gain of 1-3 dB is achievable by the proposed approach.
{"title":"Subspace-MMSE blind channel estimation for multiuser OFDM with receiver diversity","authors":"Yu-Yi Cheng, Yumin Lee, Hsueh-Jyh Li","doi":"10.1109/GLOCOM.2003.1258644","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258644","url":null,"abstract":"A receiver algorithm for OFDM with receiver diversity is proposed. The proposed receiver uses a new two-step blind channel estimation algorithm referred to as the subspace-MMSE channel estimator. Minimum mean square error linear diversity combining is then performed based on the estimated channel. Simulation results show that performance gain of 1-3 dB is achievable by the proposed approach.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121760648","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258413
A. Seeger, M. Sikora
Closed loop transmit diversity (CLTD) for FDD WCDMA relies on low-rate feedback to achieve both beamforming and diversity gain. Since the feedback channel is not immune to errors, occasionally base station (BS) uses different antenna weight vector from the one requested by mobile station (MS). Surprisingly, most of the resulting performance degradation is caused not by reduced power of the Rx signal, but by erroneous dedicated channel estimation at the MS relying on knowledge of used weight vector. In this paper we introduce a general trellis-based antenna weight verification algorithm, which attempts to detect feedback errors and determine the most likely weight vector. By exploiting the structure of CLTD schemes proposed for WCDMA with 2 and 4 BS-antennas we show methods to reduce the complexity of our algorithm. Our comparative simulations show that antenna weight verification reduces the performance degradation due to feedback errors less than 0.5 dB at 1% frame error rate for considered 4 antenna schemes.
{"title":"Antenna weight verification for closed loop transmit diversity","authors":"A. Seeger, M. Sikora","doi":"10.1109/GLOCOM.2003.1258413","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258413","url":null,"abstract":"Closed loop transmit diversity (CLTD) for FDD WCDMA relies on low-rate feedback to achieve both beamforming and diversity gain. Since the feedback channel is not immune to errors, occasionally base station (BS) uses different antenna weight vector from the one requested by mobile station (MS). Surprisingly, most of the resulting performance degradation is caused not by reduced power of the Rx signal, but by erroneous dedicated channel estimation at the MS relying on knowledge of used weight vector. In this paper we introduce a general trellis-based antenna weight verification algorithm, which attempts to detect feedback errors and determine the most likely weight vector. By exploiting the structure of CLTD schemes proposed for WCDMA with 2 and 4 BS-antennas we show methods to reduce the complexity of our algorithm. Our comparative simulations show that antenna weight verification reduces the performance degradation due to feedback errors less than 0.5 dB at 1% frame error rate for considered 4 antenna schemes.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132071959","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258516
L. Yang, Mohamed-Slim Alouini
This paper presents general expressions for the calculation of the level crossing rate of various combinations of multiple independent random processes. These new formulas are then applied to obtain the outage rate of several communication systems and networks of current interest. Applications include for example multihop communication systems with and without selection combining as well as communication networks with routing diversity.
{"title":"Level crossing rate over multiple independent random processes-an extension of the applicability of the rice formula","authors":"L. Yang, Mohamed-Slim Alouini","doi":"10.1109/GLOCOM.2003.1258516","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258516","url":null,"abstract":"This paper presents general expressions for the calculation of the level crossing rate of various combinations of multiple independent random processes. These new formulas are then applied to obtain the outage rate of several communication systems and networks of current interest. Applications include for example multihop communication systems with and without selection combining as well as communication networks with routing diversity.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132317725","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258463
Andrey Belenky, N. Ansari
A modification to the basic deterministic packet marking (DPM), a promising IP traceback scheme, to handle fragmented traffic is proposed. The modification introduces no additional bandwidth overhead, but limited additional memory requirements and processing overhead on the DPM-enabled interface.
{"title":"Accommodating fragmentation in deterministic packet marking for IP traceback","authors":"Andrey Belenky, N. Ansari","doi":"10.1109/GLOCOM.2003.1258463","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258463","url":null,"abstract":"A modification to the basic deterministic packet marking (DPM), a promising IP traceback scheme, to handle fragmented traffic is proposed. The modification introduces no additional bandwidth overhead, but limited additional memory requirements and processing overhead on the DPM-enabled interface.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132459842","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258307
Jingnong Yang, Ye Li
Orthogonal frequency division multiplexing (OFDM) is known for its efficiency in combating frequency selectivity in wireless channels. Multiple transmit and/or multiple receive (MIMO) antennas can be employed with OFDM to achieve higher diversity or capacity. In traditional OFDM MIMO systems, transmitter beamforming and receiver combining are done in the frequency domain, which requires one discrete Fourier transform (DFT) per antenna. As recently proposed, transmitter beam-forming and receiver combining can be done in time domain, and only one DFT is needed at either the transmitter or the receiver. System complexity can thus be greatly reduced at the cost of slight performance loss. We investigate the low-complexity OFDM MIMO system where the transmitter has partial side information, specifically, the knowledge of channel correlations. We show that in multiple input single output (MISO) case, time domain beamforming can be used to do two-dimensional eigen-beamforming. For MIMO case, we derive design criteria for the transmitter beamforming and receiver combining weighting vectors, and show some suboptimal solutions. Simulations show that the performance degradation of the low-complexity combining is small.
{"title":"Low complexity OFDM MIMO system based on channel correlations","authors":"Jingnong Yang, Ye Li","doi":"10.1109/GLOCOM.2003.1258307","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258307","url":null,"abstract":"Orthogonal frequency division multiplexing (OFDM) is known for its efficiency in combating frequency selectivity in wireless channels. Multiple transmit and/or multiple receive (MIMO) antennas can be employed with OFDM to achieve higher diversity or capacity. In traditional OFDM MIMO systems, transmitter beamforming and receiver combining are done in the frequency domain, which requires one discrete Fourier transform (DFT) per antenna. As recently proposed, transmitter beam-forming and receiver combining can be done in time domain, and only one DFT is needed at either the transmitter or the receiver. System complexity can thus be greatly reduced at the cost of slight performance loss. We investigate the low-complexity OFDM MIMO system where the transmitter has partial side information, specifically, the knowledge of channel correlations. We show that in multiple input single output (MISO) case, time domain beamforming can be used to do two-dimensional eigen-beamforming. For MIMO case, we derive design criteria for the transmitter beamforming and receiver combining weighting vectors, and show some suboptimal solutions. Simulations show that the performance degradation of the low-complexity combining is small.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130069545","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258711
Xi Yang, B. Ramamurthy
Next-generation optical transport networks will automatically and dynamically provision end-to-end connections. In this paper, we study the problem of inter-domain dynamic routing under a multi-layer multi-domain network model, which allows the end-to-end connections to be set up not only across multiple routing domains but also through two transport layers: the optical layer and the digital layer. In this model, a connection can traverse the domain boundary either through optical bypass or through optical-electrical-optical (O/E/O) processing. We propose an inter-domain dynamic routing scheme with modest time complexity to address the problem from an algorithmic perspective.
{"title":"Inter-domain dynamic routing in multi-layer optical transport networks","authors":"Xi Yang, B. Ramamurthy","doi":"10.1109/GLOCOM.2003.1258711","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258711","url":null,"abstract":"Next-generation optical transport networks will automatically and dynamically provision end-to-end connections. In this paper, we study the problem of inter-domain dynamic routing under a multi-layer multi-domain network model, which allows the end-to-end connections to be set up not only across multiple routing domains but also through two transport layers: the optical layer and the digital layer. In this model, a connection can traverse the domain boundary either through optical bypass or through optical-electrical-optical (O/E/O) processing. We propose an inter-domain dynamic routing scheme with modest time complexity to address the problem from an algorithmic perspective.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130440480","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 : 2003-12-01DOI: 10.1109/GLOCOM.2003.1258315
Genyuan Wang, Huiyong Liao, Haiquan Wang, X. Xia
A systematic diagonal space-time block code (cyclotomic space-time code) design is proposed by using high dimensional cyclotomic lattices and some algebraic number theory. This design can be applied to any number of transmit antennas and for a fixed number of transmit antennas, there are infinitely many cyclotomic space-time codes. It is shown that all the cyclotomic space-time codes from the design have full diversity. Furthermore, optimal cyclotomic space-time codes from the design for different numbers of transmit antennas are obtained, where the optimality is in the sense that, for a fixed mean transmission signal power, its diversity product is maximized, or for a fixed diversity product, its mean transmission signal power is minimized. Although there are some cyclotomic space-time codes existed in the literature, most of them are not optimal.
{"title":"Systematic and optimal cyclotomic space-time code designs","authors":"Genyuan Wang, Huiyong Liao, Haiquan Wang, X. Xia","doi":"10.1109/GLOCOM.2003.1258315","DOIUrl":"https://doi.org/10.1109/GLOCOM.2003.1258315","url":null,"abstract":"A systematic diagonal space-time block code (cyclotomic space-time code) design is proposed by using high dimensional cyclotomic lattices and some algebraic number theory. This design can be applied to any number of transmit antennas and for a fixed number of transmit antennas, there are infinitely many cyclotomic space-time codes. It is shown that all the cyclotomic space-time codes from the design have full diversity. Furthermore, optimal cyclotomic space-time codes from the design for different numbers of transmit antennas are obtained, where the optimality is in the sense that, for a fixed mean transmission signal power, its diversity product is maximized, or for a fixed diversity product, its mean transmission signal power is minimized. Although there are some cyclotomic space-time codes existed in the literature, most of them are not optimal.","PeriodicalId":301154,"journal":{"name":"GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130464513","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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