Pub Date : 1991-12-02DOI: 10.1109/GLOCOM.1991.188502
A. Kajiwara, M. Nakagawa
A description is presented of a direct-sequence spread-spectrum (DS/SS) block demodulator with cross-correlation canceller which can provide high capacity per unit bandwidth. In a DS/SS block demodulator, signals are from all channels recursively detected from the received packet signal stored in buffer memory, and then the cross-correlation component is removed algebraically. The simulation results show that the capacity is higher than around 45%, and good near-far resistance capability is also achieved.<>
{"title":"Spread-spectrum block demodulator with high capacity crosscorrelation canceller","authors":"A. Kajiwara, M. Nakagawa","doi":"10.1109/GLOCOM.1991.188502","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188502","url":null,"abstract":"A description is presented of a direct-sequence spread-spectrum (DS/SS) block demodulator with cross-correlation canceller which can provide high capacity per unit bandwidth. In a DS/SS block demodulator, signals are from all channels recursively detected from the received packet signal stored in buffer memory, and then the cross-correlation component is removed algebraically. The simulation results show that the capacity is higher than around 45%, and good near-far resistance capability is also achieved.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115113762","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188484
M. Bagheri, D. Kong, W. Holden, F. C. Irizarry, D. Mahoney, D. C. Larson
To study the key technical issues in SONET (synchronous optical network byte multiplexing at gigabit/s data rates and the interworking of SONET and other broadband network elements, the authors implemented an experimental SONET STS-48 (synchronous transport signal) (2.488 Gb/s) testbed with broadband user interfaces (STS-3c and higher data rates). The testbed includes a SONET-compatible experimental STS-3c to STS-48 byte multiplexer and demultiplexer. A description is presented of the architecture, implementation, and experimental results of the high-speed components of the byte multiplexer and demultiplexer. The implementation employs a combination of custom VLSI integrated circuits and off-the-shelf components for rapid prototyping and verifying the validity of the architecture.<>
{"title":"An experimental 2.488 gigabit/sec SONET STS-3c to STS-48 byte multiplexer and demultiplexer","authors":"M. Bagheri, D. Kong, W. Holden, F. C. Irizarry, D. Mahoney, D. C. Larson","doi":"10.1109/GLOCOM.1991.188484","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188484","url":null,"abstract":"To study the key technical issues in SONET (synchronous optical network byte multiplexing at gigabit/s data rates and the interworking of SONET and other broadband network elements, the authors implemented an experimental SONET STS-48 (synchronous transport signal) (2.488 Gb/s) testbed with broadband user interfaces (STS-3c and higher data rates). The testbed includes a SONET-compatible experimental STS-3c to STS-48 byte multiplexer and demultiplexer. A description is presented of the architecture, implementation, and experimental results of the high-speed components of the byte multiplexer and demultiplexer. The implementation employs a combination of custom VLSI integrated circuits and off-the-shelf components for rapid prototyping and verifying the validity of the architecture.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123333407","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188520
D. Ghosh, J. Daly
Analytical and simulation results are presented on the performance of delta networks constructed with crossbars having multiple channels per input/output (I/O) ports. The probability of internal blocking is reduced significantly when two or more parallel channels interconnect stages of crossbars. Using small buffers (about 20 packets) at the outputs of the networks a throughput exceeding 90% can be achieved by using 3 channels per port. With further increase in the number of channels and buffer size the throughput approaches 100%. These networks can be used in telecommunication switching employing asynchronous transfer mode and in multiprocessor systems.<>
{"title":"Delta networks with multiple links and shared output buffers: a high performance architecture for packet switching","authors":"D. Ghosh, J. Daly","doi":"10.1109/GLOCOM.1991.188520","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188520","url":null,"abstract":"Analytical and simulation results are presented on the performance of delta networks constructed with crossbars having multiple channels per input/output (I/O) ports. The probability of internal blocking is reduced significantly when two or more parallel channels interconnect stages of crossbars. Using small buffers (about 20 packets) at the outputs of the networks a throughput exceeding 90% can be achieved by using 3 channels per port. With further increase in the number of channels and buffer size the throughput approaches 100%. These networks can be used in telecommunication switching employing asynchronous transfer mode and in multiprocessor systems.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"226 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123217185","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188418
Chii-Min Loau, Ji-Tsu Wu
A novel DPLL (digital phase-locked loop) has been designed and implemented. A novel phase locking technique called phase-hopping was developed. Key features of the phase-hopping DPLL (PHDPLL) are high-speed desynchronization and very narrow bandwidth (below 1 Hz). Moreover, it can be integrated with other operation circuits on a single chip by VLSI technology. Loop characteristics of the PHDPLL have been analyzed and verified by software simulation and hardware test. The optimal parameters and performance of the PHDPLL for SONET (Synchronous Optical NETwork) desynchronizer applications are presented. When the loop bandwidth of the PHDPLL is below 0.66 Hz, it is observed that the desynchronizer's output jitter meets the 1.5 unit interval peak-to-peak jitter specification.<>
{"title":"PHDPLL for SONET desynchronizer","authors":"Chii-Min Loau, Ji-Tsu Wu","doi":"10.1109/GLOCOM.1991.188418","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188418","url":null,"abstract":"A novel DPLL (digital phase-locked loop) has been designed and implemented. A novel phase locking technique called phase-hopping was developed. Key features of the phase-hopping DPLL (PHDPLL) are high-speed desynchronization and very narrow bandwidth (below 1 Hz). Moreover, it can be integrated with other operation circuits on a single chip by VLSI technology. Loop characteristics of the PHDPLL have been analyzed and verified by software simulation and hardware test. The optimal parameters and performance of the PHDPLL for SONET (Synchronous Optical NETwork) desynchronizer applications are presented. When the loop bandwidth of the PHDPLL is below 0.66 Hz, it is observed that the desynchronizer's output jitter meets the 1.5 unit interval peak-to-peak jitter specification.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121299224","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188395
F. Guillemin, J. Roberts
Cells arriving at an ATM (asynchronous transfer mode) network experience random delays due to queuing in upstream multiplexing stages. The alteration of the initial periodic nature of a constant bit rate cell stream due to such delays is the phenomenon of jitter. An assumption of Markovian dependence between the delays of successive cells makes it possible to calculate various quantities of interest for characterizing the jitter. This assumption is appropriate for two ATM multiplex models, and it was possible to investigate the effects of different source and multiplex parameters on the degree of jitter introduced. Jumping window and leaky bucket mechanisms have been dimensioned to enforce the peak rate of jittered streams. The leaky bucket is seen to be considerably more responsive than the jumping window. A synthetic characterization of jitter consists in the remote delay quantile divided by the period of the considered stream. This is sufficient to dimension the leaky bucket for one of the considered multiplex models and supports the heuristic approach of G. Niestegge (1990).<>
{"title":"Jitter and bandwidth enforcement","authors":"F. Guillemin, J. Roberts","doi":"10.1109/GLOCOM.1991.188395","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188395","url":null,"abstract":"Cells arriving at an ATM (asynchronous transfer mode) network experience random delays due to queuing in upstream multiplexing stages. The alteration of the initial periodic nature of a constant bit rate cell stream due to such delays is the phenomenon of jitter. An assumption of Markovian dependence between the delays of successive cells makes it possible to calculate various quantities of interest for characterizing the jitter. This assumption is appropriate for two ATM multiplex models, and it was possible to investigate the effects of different source and multiplex parameters on the degree of jitter introduced. Jumping window and leaky bucket mechanisms have been dimensioned to enforce the peak rate of jittered streams. The leaky bucket is seen to be considerably more responsive than the jumping window. A synthetic characterization of jitter consists in the remote delay quantile divided by the period of the considered stream. This is sufficient to dimension the leaky bucket for one of the considered multiplex models and supports the heuristic approach of G. Niestegge (1990).<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"364 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124575440","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188437
J. Ventura-Traveset, L. Bella, H. Bessai, G. Hofmann
The implementation and test of a flexible digital multi-frequency time division multiple access (MF-TDMA) modulator are presented. The modulator is able to work at several frequencies (frequency hopping) on a burst basis without preambles or guardtimes. After a brief review of some satellite concepts (e.g., MF-TDMA, onboard processor, and traffic efficiency), direct-in-band modulation is introduced as the technique selected for the digital design of this frequency hopping modulator. A mixed Si/GaAs technology has been chosen for the hardware implementation and some tests are presented to show the good performance of the device.<>
{"title":"A flexible digital multicarrier modulator for multi-frequency TDMA satellite transmission","authors":"J. Ventura-Traveset, L. Bella, H. Bessai, G. Hofmann","doi":"10.1109/GLOCOM.1991.188437","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188437","url":null,"abstract":"The implementation and test of a flexible digital multi-frequency time division multiple access (MF-TDMA) modulator are presented. The modulator is able to work at several frequencies (frequency hopping) on a burst basis without preambles or guardtimes. After a brief review of some satellite concepts (e.g., MF-TDMA, onboard processor, and traffic efficiency), direct-in-band modulation is introduced as the technique selected for the digital design of this frequency hopping modulator. A mixed Si/GaAs technology has been chosen for the hardware implementation and some tests are presented to show the good performance of the device.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124624150","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188639
S. Liew
The author investigates the general problem of multicast routing in the three-stage Clos switching network, with point-to-point routing as a special case. An optimal and a heuristic algorithm have been designed and tested. The results show that the heuristic algorithm can find multicast routes that are close to optimal within a response time that is significantly lower than that of the optimal algorithm. Further analysis of the experimental data suggests a hybrid implementation in which the optimal and heuristic algorithms are run in parallel with a set time limit. The algorithms and the discussion provided also apply to other networks, including wide-area communication networks, with a two-hop structure.<>
{"title":"Multicast routing algorithms for 3-stage Clos ATM switching networks","authors":"S. Liew","doi":"10.1109/GLOCOM.1991.188639","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188639","url":null,"abstract":"The author investigates the general problem of multicast routing in the three-stage Clos switching network, with point-to-point routing as a special case. An optimal and a heuristic algorithm have been designed and tested. The results show that the heuristic algorithm can find multicast routes that are close to optimal within a response time that is significantly lower than that of the optimal algorithm. Further analysis of the experimental data suggests a hybrid implementation in which the optimal and heuristic algorithms are run in parallel with a set time limit. The algorithms and the discussion provided also apply to other networks, including wide-area communication networks, with a two-hop structure.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114678077","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188416
V. Jain, A.B. Asgill, P. Bobrek
The authors present a purely digital timing recovery scheme for optical OOK receivers, which offers the advantages of low hardware complexity and low jitter. In this technique, the computation of the timing function is based on symbol-rate samples of the received signal. A gain scheduling strategy is used for the timing updates; a short training set of symbols accompanied by large gain for the timing updates is followed by data symbols and low gain for the timing updates. This allows the use of large correction step sizes during training, leading to fast convergence. It is particularly suitable for an all digital optical system.<>
{"title":"Synchronization technique for optical OOK receivers","authors":"V. Jain, A.B. Asgill, P. Bobrek","doi":"10.1109/GLOCOM.1991.188416","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188416","url":null,"abstract":"The authors present a purely digital timing recovery scheme for optical OOK receivers, which offers the advantages of low hardware complexity and low jitter. In this technique, the computation of the timing function is based on symbol-rate samples of the received signal. A gain scheduling strategy is used for the timing updates; a short training set of symbols accompanied by large gain for the timing updates is followed by data symbols and low gain for the timing updates. This allows the use of large correction step sizes during training, leading to fast convergence. It is particularly suitable for an all digital optical system.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123423398","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188449
L. Bickers, I. Cade, K. James, S. James
The proposal of new network architectures for the access network, such as TPON (telephony over a passive optical network), led to the study of ways in which the new architecture can be integrated into existing systems. A testbed designed to explore the integration issues is described. Emphasis is placed on the operational experience gained using the testbed. The key objectives of the testbed were to determine the optimum operations and maintenance (O&M) procedures to allow the introduction of TPON systems into BT's existing O&M architecture; to identify the network management requirements; and to gain an improved understanding of the wider implications for mass deployment of fiber in the loop. The design of the testbed involved a passive optical network, a head-end multiplexer, and a remote-end multiplexer. The O&M development process of iterating procedure definition, prototyping, experimentation, and evaluation has proven successful in helping to define the optimum O&M procedures and tools.<>
{"title":"Operations and maintenance experimental testbed for a business TPON system","authors":"L. Bickers, I. Cade, K. James, S. James","doi":"10.1109/GLOCOM.1991.188449","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188449","url":null,"abstract":"The proposal of new network architectures for the access network, such as TPON (telephony over a passive optical network), led to the study of ways in which the new architecture can be integrated into existing systems. A testbed designed to explore the integration issues is described. Emphasis is placed on the operational experience gained using the testbed. The key objectives of the testbed were to determine the optimum operations and maintenance (O&M) procedures to allow the introduction of TPON systems into BT's existing O&M architecture; to identify the network management requirements; and to gain an improved understanding of the wider implications for mass deployment of fiber in the loop. The design of the testbed involved a passive optical network, a head-end multiplexer, and a remote-end multiplexer. The O&M development process of iterating procedure definition, prototyping, experimentation, and evaluation has proven successful in helping to define the optimum O&M procedures and tools.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124036375","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 : 1991-12-02DOI: 10.1109/GLOCOM.1991.188433
H. A. Henriques, F. Abbas, M. Nakhla
The authors present results of laboratory measurements of the power spectral density of various types of satellite television carriers modulated with live video in a way that can be readily utilized by satellite network operators wishing to protect their narrowband digital carriers according to CCIR Recommendation 523. From these results, it can be seen that, although for television carriers modulated with energy dispersal signal alone a large improvement in the interference situation can be obtained by replacing frame rate energy dispersal with other types of waveforms, the modulation of the carrier with live video will limit the benefit of the improvement since it will now represent the worst case. For this reason, a special operational procedure for the transmission of television carriers is suggested which could improve the interference situation without the need to replace the frame rate energy dispersal signal.<>
{"title":"Interference from television carriers into narrowband digital carriers","authors":"H. A. Henriques, F. Abbas, M. Nakhla","doi":"10.1109/GLOCOM.1991.188433","DOIUrl":"https://doi.org/10.1109/GLOCOM.1991.188433","url":null,"abstract":"The authors present results of laboratory measurements of the power spectral density of various types of satellite television carriers modulated with live video in a way that can be readily utilized by satellite network operators wishing to protect their narrowband digital carriers according to CCIR Recommendation 523. From these results, it can be seen that, although for television carriers modulated with energy dispersal signal alone a large improvement in the interference situation can be obtained by replacing frame rate energy dispersal with other types of waveforms, the modulation of the carrier with live video will limit the benefit of the improvement since it will now represent the worst case. For this reason, a special operational procedure for the transmission of television carriers is suggested which could improve the interference situation without the need to replace the frame rate energy dispersal signal.<<ETX>>","PeriodicalId":343080,"journal":{"name":"IEEE Global Telecommunications Conference GLOBECOM '91: Countdown to the New Millennium. Conference Record","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129592651","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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