M. Yacoub, A. de Toledo, P. Gomez, P. Jeszensky, Edson B. R. Feris
This paper proposes novel reuse patterns for a microcellular network based on a square grid. An initial carrier-to-interference ratio assessment for these patterns considers the mobiles positioned at the worst-case condition and the system operating at full load. Among the possible reuse patterns (1, 2, 4, 5, 8, 9, 10, 13, ...microcells per cluster) the performance analysis investigates systems with clusters of 5, 8, 9, and 10 microcells. The results show a substantial difference in performance for the uplink and downlink, with the former performing less satisfactorily than the latter and with this difference diminishing as the size of the cluster increases. Both the 10- and the 9-microcell clusters exhibit outstanding performance and, if appropriately explored, a remarkable trade-off between capacity and interference may be encountered in the 5-microcell cluster.
{"title":"Novel reuse patterns for microcellular networks","authors":"M. Yacoub, A. de Toledo, P. Gomez, P. Jeszensky, Edson B. R. Feris","doi":"10.1109/ITS.1998.718422","DOIUrl":"https://doi.org/10.1109/ITS.1998.718422","url":null,"abstract":"This paper proposes novel reuse patterns for a microcellular network based on a square grid. An initial carrier-to-interference ratio assessment for these patterns considers the mobiles positioned at the worst-case condition and the system operating at full load. Among the possible reuse patterns (1, 2, 4, 5, 8, 9, 10, 13, ...microcells per cluster) the performance analysis investigates systems with clusters of 5, 8, 9, and 10 microcells. The results show a substantial difference in performance for the uplink and downlink, with the former performing less satisfactorily than the latter and with this difference diminishing as the size of the cluster increases. Both the 10- and the 9-microcell clusters exhibit outstanding performance and, if appropriately explored, a remarkable trade-off between capacity and interference may be encountered in the 5-microcell cluster.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115741508","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}
C. Gaibisso, G. Gambosi, M. Lancia, G. Martufi, E.A. Mastromartino
The use of a mobile code, partly interpreted language such as Java is investigated as a tool to build highly portable implementations of multimedia communication protocols. In particular, we concentrate on the implementation of the real-time protocol and focus our attention on three main issues: first, we evaluate the quality and accuracy of the services offered by some relevant primitive operations as they are provided on different Java platforms; second, we concentrate on a suitable object-oriented design which makes RTP functionalities both well-integrated and easily accessible; finally, we perform an overall evaluation of the efficiency of the proposed implementation both in terms of resulting packet loss and delay jitter.
{"title":"Mobile code implementation of the RTP protocol in Java: design choices and evaluation","authors":"C. Gaibisso, G. Gambosi, M. Lancia, G. Martufi, E.A. Mastromartino","doi":"10.1109/ITS.1998.718472","DOIUrl":"https://doi.org/10.1109/ITS.1998.718472","url":null,"abstract":"The use of a mobile code, partly interpreted language such as Java is investigated as a tool to build highly portable implementations of multimedia communication protocols. In particular, we concentrate on the implementation of the real-time protocol and focus our attention on three main issues: first, we evaluate the quality and accuracy of the services offered by some relevant primitive operations as they are provided on different Java platforms; second, we concentrate on a suitable object-oriented design which makes RTP functionalities both well-integrated and easily accessible; finally, we perform an overall evaluation of the efficiency of the proposed implementation both in terms of resulting packet loss and delay jitter.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"736 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116991659","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}
Wide-band microstrip antennas are still a challenge and in the last couple of years a number of new configurations have been reported. Most of these configurations are multilayer patch antennas with some of them achieving up to 40% in bandwidth. Recently, another new geometry has been reported, a single patch fed by a three-dimensional feed line, which in essence is a very tall patch fed by a wide-band dipole. This antenna is reported to exhibit a 90-100% bandwidth for VSWR <2:1; towards the high end of the band, however, the radiation from the wide-band dipole is too strong and interferes with the patch pattern resulting in a high crosspolarization level. In the array environment, though, the crosspolarization is reduced by the array factor. The paper analyzes the performance of an eight-element array and its scanning capabilities. To avoid grading lobes the radiating elements have to be very close to each other, so the impact of the mutual coupling is also investigated.
{"title":"A new class of wide-band microstrip arrays","authors":"N. Herscovici","doi":"10.1109/ITS.1998.718430","DOIUrl":"https://doi.org/10.1109/ITS.1998.718430","url":null,"abstract":"Wide-band microstrip antennas are still a challenge and in the last couple of years a number of new configurations have been reported. Most of these configurations are multilayer patch antennas with some of them achieving up to 40% in bandwidth. Recently, another new geometry has been reported, a single patch fed by a three-dimensional feed line, which in essence is a very tall patch fed by a wide-band dipole. This antenna is reported to exhibit a 90-100% bandwidth for VSWR <2:1; towards the high end of the band, however, the radiation from the wide-band dipole is too strong and interferes with the patch pattern resulting in a high crosspolarization level. In the array environment, though, the crosspolarization is reduced by the array factor. The paper analyzes the performance of an eight-element array and its scanning capabilities. To avoid grading lobes the radiating elements have to be very close to each other, so the impact of the mutual coupling is also investigated.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124903398","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}
The performance of dual space diversity reception combined with a decision feedback equalizer (DFE) in an indoor wireless channel at 57.5 GHz over arched and rectangular buildings is investigated. The impulse responses of arched and rectangular buildings for any transmitter-receiver location are computed by shooting and bouncing ray/image techniques. By using the impulse responses of these multipath channels, the impact of shapes of buildings is presented and the bit error rate performance of a BPSK (binary phase shift keying) system with phase and timing recovery circuits are also calculated. Moreover, a dual space antenna diversity technique and decision feedback equalizer with four forward and three feedback taps are used to combat the multipath fading. Numerical results show that the mean RMS (root mean square) delay spread for the arched building is smaller than that for the rectangular building. In addition, it is also found that the transmission rate can be up to 20 Mbps for an indoor millimeter-wave channel of these two buildings by using dual space diversity and DFE.
{"title":"Dual diversity combining and decision feedback equalizer in indoor wireless channel at 57.5 GHz","authors":"Shi-Cheng Hung, Ching-Chuan Chiu","doi":"10.1109/ITS.1998.713136","DOIUrl":"https://doi.org/10.1109/ITS.1998.713136","url":null,"abstract":"The performance of dual space diversity reception combined with a decision feedback equalizer (DFE) in an indoor wireless channel at 57.5 GHz over arched and rectangular buildings is investigated. The impulse responses of arched and rectangular buildings for any transmitter-receiver location are computed by shooting and bouncing ray/image techniques. By using the impulse responses of these multipath channels, the impact of shapes of buildings is presented and the bit error rate performance of a BPSK (binary phase shift keying) system with phase and timing recovery circuits are also calculated. Moreover, a dual space antenna diversity technique and decision feedback equalizer with four forward and three feedback taps are used to combat the multipath fading. Numerical results show that the mean RMS (root mean square) delay spread for the arched building is smaller than that for the rectangular building. In addition, it is also found that the transmission rate can be up to 20 Mbps for an indoor millimeter-wave channel of these two buildings by using dual space diversity and DFE.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"30 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123737322","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}
Aggregate data traffic generated by LAN interconnection over ATM service will certainly be a major component of ATM network traffic. Therefore, it is important to correctly dimension ATM networks in order to support this kind of traffic. In order to achieve this goal, we need a precise traffic model. Bellcore researchers, based on rigorous statistical analyses of a great amount of aggregate Ethernet traffic, have proposed the self-similar or fractal model for this kind of traffic. This model has very distinct statistical properties when compared to traditional aggregate data traffic models such as the Poisson, and the exponential ON-OFF model. Additionally the pseudo-self-similar model, a Markovian model that behaves close to self-similar traffic, has been proposed. This model aims at easing the performance evaluation of ATM networks with self-similar traffic by re-using the analytic methods developed for Markovian models. We study the statistical multiplexing of aggregate data traffic in ATM networks. We aim at determining the impact of the self-similar model in statistical multiplexing (with respect to the Poisson and exponential ON-OFF models) and the feasibility of using the pseudo-self-similar model in this kind of study.
{"title":"Statistical multiplexing of aggregate data traffic in ATM networks","authors":"A.L.I. Oliveira, J. Monteiro","doi":"10.1109/ITS.1998.713100","DOIUrl":"https://doi.org/10.1109/ITS.1998.713100","url":null,"abstract":"Aggregate data traffic generated by LAN interconnection over ATM service will certainly be a major component of ATM network traffic. Therefore, it is important to correctly dimension ATM networks in order to support this kind of traffic. In order to achieve this goal, we need a precise traffic model. Bellcore researchers, based on rigorous statistical analyses of a great amount of aggregate Ethernet traffic, have proposed the self-similar or fractal model for this kind of traffic. This model has very distinct statistical properties when compared to traditional aggregate data traffic models such as the Poisson, and the exponential ON-OFF model. Additionally the pseudo-self-similar model, a Markovian model that behaves close to self-similar traffic, has been proposed. This model aims at easing the performance evaluation of ATM networks with self-similar traffic by re-using the analytic methods developed for Markovian models. We study the statistical multiplexing of aggregate data traffic in ATM networks. We aim at determining the impact of the self-similar model in statistical multiplexing (with respect to the Poisson and exponential ON-OFF models) and the feasibility of using the pseudo-self-similar model in this kind of study.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116014627","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}
The objective of this paper is the study of the broadband-integrated services digital network (B-ISDN) meta-signalling protocol. The new paradigm that will be introduced to the service offered to the user and to his environment is discussed, and the meta-signalling protocol is described, as an important part of this new paradigm. An implementation of the meta-signalling management for a B-ISDN user-network interface and software to control these management functions are proposed.
{"title":"A meta-signalling management implementation for public ATM networks","authors":"W.B. Fortes, R.R. Scarabucci","doi":"10.1109/ITS.1998.718440","DOIUrl":"https://doi.org/10.1109/ITS.1998.718440","url":null,"abstract":"The objective of this paper is the study of the broadband-integrated services digital network (B-ISDN) meta-signalling protocol. The new paradigm that will be introduced to the service offered to the user and to his environment is discussed, and the meta-signalling protocol is described, as an important part of this new paradigm. An implementation of the meta-signalling management for a B-ISDN user-network interface and software to control these management functions are proposed.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114421629","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}
The classical analysis of the downlink power control in CDMA cellular systems neglects the background noise in the mobile receivers and leads to a solution for the equalized signal-to-interference ratio by solving an eigenvalue problem. By considering the background noise, we obtain a general solution that includes the previous result and is optimal in the sense that it minimizes the transmitted power. Detailed illustration is presented for an homogeneous system and a general formulation is given for non-homogeneous systems.
{"title":"General analysis of downlink power control in CDMA systems","authors":"A. Da Rocha Lima, J. Brandão","doi":"10.1109/ITS.1998.713112","DOIUrl":"https://doi.org/10.1109/ITS.1998.713112","url":null,"abstract":"The classical analysis of the downlink power control in CDMA cellular systems neglects the background noise in the mobile receivers and leads to a solution for the equalized signal-to-interference ratio by solving an eigenvalue problem. By considering the background noise, we obtain a general solution that includes the previous result and is optimal in the sense that it minimizes the transmitted power. Detailed illustration is presented for an homogeneous system and a general formulation is given for non-homogeneous systems.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114545692","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}
Luis J. de la Cruz, Esteve Pallarès, J. Alins, J. Mata
Recent studies and traffic measurements have shown that variable bit rate (VBR) video traffic, as well as local area network (LAN) traffic, exhibits long-range dependence (LRD). When this kind of traffic is transmitted over ATM networks, the LRD property implies a larger requirement in buffer allocation and channel capacity. A new fractional ARIMA model for VBR MPEG video traffic at frame level is presented. The fractional integrative component of the model is based on a process called "fractional differencing". The model is obtained from three very long sequences. It is used to synthesize artificial traffic, which presents the desired LRD.
{"title":"Self-similar traffic generation using a fractional ARIMA model. Application to the VBR MPEG video traffic","authors":"Luis J. de la Cruz, Esteve Pallarès, J. Alins, J. Mata","doi":"10.1109/ITS.1998.713099","DOIUrl":"https://doi.org/10.1109/ITS.1998.713099","url":null,"abstract":"Recent studies and traffic measurements have shown that variable bit rate (VBR) video traffic, as well as local area network (LAN) traffic, exhibits long-range dependence (LRD). When this kind of traffic is transmitted over ATM networks, the LRD property implies a larger requirement in buffer allocation and channel capacity. A new fractional ARIMA model for VBR MPEG video traffic at frame level is presented. The fractional integrative component of the model is based on a process called \"fractional differencing\". The model is obtained from three very long sequences. It is used to synthesize artificial traffic, which presents the desired LRD.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129719588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the last few years, various types of wireless networks have become available and cost-effective for commercial applications. In order to become a real alternative to traditional wireline telecommunications, wireless networks should provide competitive quality, reliability and availability of service. These requirements imply a need for a wireless fault management system with features similar to those incorporated in wireline counterparts. Despite a significant need for fault management in wireless networks, there has been almost no such proposals nor deployments. Existing wireless fault management systems provide management of mobile switching centers (MSG), rarely of base stations. Traditionally, base stations measure signal quality, and send alarms to a network management center (NMC) if some of the signal parameters are out of allowed range. This solution has been proven to be insufficient since it is possible to detect the signal quality at a base station's site, not at a subscriber's site. The proposed overlay signal monitoring system collects various signal parameters at a subscriber's site, determines if these parameters are within the allowed range of values, and generates an alarm if it is not the case. The NMC receives alarms and handles them as in wireline networks. This paper describes elements of the signal monitoring system, and how it detects and locates base station failures, signal degradation, co-channel and adjacent channel interference in a network. A mechanism for alarm generation and reporting is also described, as well as the interface between the signal monitoring system and existing network management center.
{"title":"Signal monitoring system for wireless network operation and management","authors":"J. Vucetic, P. Kline","doi":"10.1109/ITS.1998.713135","DOIUrl":"https://doi.org/10.1109/ITS.1998.713135","url":null,"abstract":"In the last few years, various types of wireless networks have become available and cost-effective for commercial applications. In order to become a real alternative to traditional wireline telecommunications, wireless networks should provide competitive quality, reliability and availability of service. These requirements imply a need for a wireless fault management system with features similar to those incorporated in wireline counterparts. Despite a significant need for fault management in wireless networks, there has been almost no such proposals nor deployments. Existing wireless fault management systems provide management of mobile switching centers (MSG), rarely of base stations. Traditionally, base stations measure signal quality, and send alarms to a network management center (NMC) if some of the signal parameters are out of allowed range. This solution has been proven to be insufficient since it is possible to detect the signal quality at a base station's site, not at a subscriber's site. The proposed overlay signal monitoring system collects various signal parameters at a subscriber's site, determines if these parameters are within the allowed range of values, and generates an alarm if it is not the case. The NMC receives alarms and handles them as in wireline networks. This paper describes elements of the signal monitoring system, and how it detects and locates base station failures, signal degradation, co-channel and adjacent channel interference in a network. A mechanism for alarm generation and reporting is also described, as well as the interface between the signal monitoring system and existing network management center.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128241487","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}
We propose and analyze a quality-based admission control policy for the integration of voice and data in DS-CDMA systems. The data users are assigned a higher transmission power level over voice users to achieve a lower bit error rate. The admission policy determines the acceptance of a call request based on its specific quality of service (QoS) and the network resources. The system ensures that an accepted voice call enjoys its specific QoS without degrading the quality of existing voice calls. A power-control-based and a variable-rate-based admission policy are proposed and compared.
本文提出并分析了一种基于质量的DS-CDMA系统话音数据融合准入控制策略。数据用户被赋予比语音用户更高的传输功率，以实现更低的误码率。允许策略根据呼叫请求的特定QoS (quality of service)和网络资源来决定是否接受呼叫请求。系统可确保已接收的语音呼叫享有特定的QoS，而不会降低现有语音呼叫的质量。提出了基于功率控制和基于可变速率的录取策略，并进行了比较。
{"title":"Access control schemes for DS-CDMA cellular system supporting an integrated voice/data traffic","authors":"H. Um","doi":"10.1109/ITS.1998.713094","DOIUrl":"https://doi.org/10.1109/ITS.1998.713094","url":null,"abstract":"We propose and analyze a quality-based admission control policy for the integration of voice and data in DS-CDMA systems. The data users are assigned a higher transmission power level over voice users to achieve a lower bit error rate. The admission policy determines the acceptance of a call request based on its specific quality of service (QoS) and the network resources. The system ensures that an accepted voice call enjoys its specific QoS without degrading the quality of existing voice calls. A power-control-based and a variable-rate-based admission policy are proposed and compared.","PeriodicalId":205350,"journal":{"name":"ITS'98 Proceedings. SBT/IEEE International Telecommunications Symposium (Cat. No.98EX202)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130418510","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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