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On the performance of the DQRUMA with different scheduling algorithms for multimedia traffic in an indoor environment for W-ATM networks W-ATM网络中不同调度算法下DQRUMA处理室内多媒体流量的性能研究
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923347
C. Verikoukis, J. Olmos
{"title":"On the performance of the DQRUMA with different scheduling algorithms for multimedia traffic in an indoor environment for W-ATM networks","authors":"C. Verikoukis, J. Olmos","doi":"10.1109/SCVT.2000.923347","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923347","url":null,"abstract":"The performance of the DQRUMA MAC protocol for multimedia traffic in a realistic indoor environment using the guarantee bandwidth minimising delay (GBMD) scheduling policy is evaluated by simulations. The efficiency of the GBMD is compared to the corresponding with the FCFS with priorities and the RR with priorities. The analysis was carried out for a typical multicarrier modulation scheme (OFDM) with QPSK modulation on each carrier. The hidden Markov model (HMM) is used for modelling the physical layer of the system, while a type-II hybrid-ARQ protocol based on punctured RS codes is applied in the LLC layer. The performance of each ATM traffic service in terms of mean delay, cell loss rate (CLR), and the standard deviation, the 99.9 percentile, and pdf of the delay is presented.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"55 1","pages":"103-108"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90683888","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}
引用次数: 0
Burst-by-burst adaptive wideband wireless video telephony 突发自适应宽带无线视频电话
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923365
L. Hanzo, C. Wong, P. Cherriman
{"title":"Burst-by-burst adaptive wideband wireless video telephony","authors":"L. Hanzo, C. Wong, P. Cherriman","doi":"10.1109/SCVT.2000.923365","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923365","url":null,"abstract":"The design trade-offs of interactive wireless video systems are discussed and performance comparisons are provided both in the context of second- and third-generation wireless videophone systems. We commence our discussions by a comparative study of arbitrarily programmable, but fixed-rate, videophone codecs using quarter common intermediate format (QCIF) video sequences scanned at 10 frames/s. These proprietary codecs were designed to allow direct replacement of mobile radio voice codecs in second generation wireless systems, such as the Pan-European GSM, the American IS-54 and IS-95 as well as the Japanese systems, operating at 13, 8, 9.6 and 6.7 kbps, respectively, although better video quality is maintained over higher-rate, 32 kbps cordless systems, such as the Japanese PHS and the European DECT and CT2 systems. From the range of codecs investigated, best overall performance was achieved by our vector-quantised codecs, followed by the discrete cosine transformed and the quadtree-based schemes. The associated video peak signal-to-noise ratio (PSNR) was around 30 dB, while the subjective video quality can be assessed under http://www-mobile.ecs.soton.ac.uk. A range of multimode wireless transceivers is also proposed. The second part of the paper is dedicated to burst-by-burst (BbB) adaptive wireless video transceivers employing the standard H.263 codec. It is demonstrated that the proposed BbB adaptive transceivers provide an improved video performance in comparison to their statically reconfigured counterparts in the context of both wideband BbB adaptive quadrature amplitude modulation (AQAM) transceivers and the joint-detection based code division multiple access (CDMA) transceivers of the third generation systems.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"34 1","pages":"215-232"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73508390","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}
引用次数: 4
Resource allocation for frequency-selective multiple access channels with adaptive QAM modulation 自适应QAM调制的选频多址信道资源分配
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923360
T. Sartenaer, L. Vandendorpe
{"title":"Resource allocation for frequency-selective multiple access channels with adaptive QAM modulation","authors":"T. Sartenaer, L. Vandendorpe","doi":"10.1109/SCVT.2000.923360","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923360","url":null,"abstract":"This paper addresses the problem of resource allocation in a general multiple access scenario. Powers are supposed to be fixed and maximization of the bit rate is put as an objective, with a number of fairness constraints that provide each user with individual bit rates in proportion with their needs. Linear programming algorithms give the solution for the matched filter bound. As soon as the channels are frequency-selective, the use of joint detectors is proposed. An adapted allocation algorithm is given, that implies the update of the joint detector performance for each iteration. A fast update algorithm is also proposed. Results are given for a 5-user powerline access network.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"17 1","pages":"178-185"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79250207","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}
引用次数: 1
The effect of handover quality on buffering requirements in WATM WATM中切换质量对缓冲需求的影响
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923345
T. Whitley, M. Beach
{"title":"The effect of handover quality on buffering requirements in WATM","authors":"T. Whitley, M. Beach","doi":"10.1109/SCVT.2000.923345","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923345","url":null,"abstract":"In order to maintain quality of service (QoS) guarantees during a wireless ATM handover, the cell stream must be buffered while a new connection is established. Once handoff is complete, the buffers can be emptied and normal transmission resumes. This prevents cell loss but can introduce cell delay variation (CDV) which is detrimental to real time and delay sensitive services. Additional flow control buffers can overcome this; however, the quality of the handoff will greatly affect the loading on these buffers. In this paper a lossless handover method is analysed using the Opnet simulation tool, varying qualities of handoff are modelled and the buffer loading is measured. Practical data gathered using a 5 GHz variable rate modem is included in the model to provide radio performance characteristics and allow cell retransmission rates and other factors that will affect the handover to be incorporated. The results from the Opnet simulation are presented including cell delay and delay variation, utilisation and loading of buffers and handover efficiency.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"5 1","pages":"88-93"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84610233","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}
引用次数: 0
Performance evaluation of connection admission control for W-CDMA networks using dynamic system simulations 基于动态系统仿真的W-CDMA网络接入控制性能评价
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923359
J. Mueckenheim, U. Bernhard, H. Pampel, P. Gunreben
{"title":"Performance evaluation of connection admission control for W-CDMA networks using dynamic system simulations","authors":"J. Mueckenheim, U. Bernhard, H. Pampel, P. Gunreben","doi":"10.1109/SCVT.2000.923359","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923359","url":null,"abstract":"Connection admission control (CAC) is an essential technical for code-division multiple-access (CDMA) mobile cellular communication systems. It has a strong impact on the system quality and capacity. In this paper, we investigate the UMTS wideband CDMA technology and focus on the impact of the CAC algorithms with respect to the overall network performance. Of particular interest within this context is the choice of a suitable admission criterion, i.e. when to admit or deny new service requests. For the investigations, we use a dynamic network simulation tool named STEAM (simulation tool for the evaluation of algorithms in mobile networks). The investigations on CAC reveal that e.g. by setting the admission threshold there is a trade-off between blocking and dropping of users: when increasing the threshold the blocking rate decreases while the dropping rate increases and vice versa. Hence, the operator is able to adjust the network quality in terms of blocking and dropping by setting control parameters and thresholds. In this contribution, we show the impact of these parameters and give practical design rules for network operations. By using the proposed control algorithm, it is possible to achieve high system capacities while the system load is still well controlled.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"35 1","pages":"174-177"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86701818","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}
引用次数: 9
Switched beam antennas performance evaluation and capacity increase for UMTS systems 用于UMTS系统的交换波束天线性能评估和容量增加
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923343
R. M. Rodríguez-Osorio, D. Martinez Veguillas, L. de Haro Ariet, M. Calvo Ramón
{"title":"Switched beam antennas performance evaluation and capacity increase for UMTS systems","authors":"R. M. Rodríguez-Osorio, D. Martinez Veguillas, L. de Haro Ariet, M. Calvo Ramón","doi":"10.1109/SCVT.2000.923343","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923343","url":null,"abstract":"New mobile communication services are appearing, and the rate of demand is rapidly increasing. New technologies are needed to give service to the higher number of users with the minimum of spectrum requirements. One of these technologies is the dynamic reconfiguration of the antenna radiation pattern at the base station site. Although this technique can be applied to TDMA and FDMA systems, the main improvement is obtained when using CDMA. These antenna systems pretend to minimize the interference power received from non-desired users, and maximize C/I values. This paper presents simulation results obtained for the vehicular scenario of W-CDMA UMTS macrocellular systems using switched beam antenna technology. Performance improvement obtained with respect to 120/spl deg/ three-sectorial antenna systems is shown. Both intracell and out-of-cell interference are calculated, and user mobility is taken into account in the simulator.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"72 1","pages":"82-87"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86264409","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}
引用次数: 11
Doubling CDMA capacity by in-cell sequence reuse and soft interference cancellation 通过小区内序列复用和软干扰消除实现CDMA容量翻番
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923357
F. Vanhaverbeke, M. Moeneclaey, H. Sari
{"title":"Doubling CDMA capacity by in-cell sequence reuse and soft interference cancellation","authors":"F. Vanhaverbeke, M. Moeneclaey, H. Sari","doi":"10.1109/SCVT.2000.923357","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923357","url":null,"abstract":"We investigate a multiple access concept consisting of a combined OCDMA/OCDMA scheme that can accommodate up to 2N users, with N denoting the spreading factor. Hence, the capacity of this scheme is twice the capacity of conventional OCDMA. Multiuser interference is reduced by means of iterative soft interference cancellation. For maximum load (i.e., 2N active users), the BER performance improves with increasing N. The resulting SNR degradation at BER=10/sup -4/ is found to be negligibly small as soon as N/spl ges/64. Our performance results show the superiority of OCDMA/OCDMA over PN-CDMA, assuming both systems have spreading factor N, accommodate 2N users, and apply soft interference cancellation. In addition, the computational complexity of OCDMA/OCDMA is only half that of PN-CDMA.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"117 1","pages":"160-165"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87086625","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}
引用次数: 1
Comparison of the sensitivities of MC-CDMA and MC-DS-CDMA to carrier frequency offset MC-CDMA和MC-DS-CDMA对载波频偏的灵敏度比较
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923358
H. Steendam, M. Moeneclaey
{"title":"Comparison of the sensitivities of MC-CDMA and MC-DS-CDMA to carrier frequency offset","authors":"H. Steendam, M. Moeneclaey","doi":"10.1109/SCVT.2000.923358","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923358","url":null,"abstract":"We consider the effect of carrier frequency offset on the performance of MC-CDMA and MC-DS-CDMA, which are both combinations of the multicarrier transmission technique and the CDMA multiple access technique. We show that both systems strongly degrade in the presence of a carrier frequency offset. Furthermore, we show that, for a given spreading factor, the MC-DS-CDMA system is less (more) sensitive to carrier frequency offset than MC-CDMA when the number of modulated carriers in the former system is smaller (larger) than the spreading factor.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"114 1","pages":"166-173"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79910461","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}
引用次数: 22
Optimization of the handover algorithm based on the position of the mobile terminals 基于移动终端位置的切换算法优化
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923356
S. Kyriazakos, D. Drakoulis, G. Karetsos
{"title":"Optimization of the handover algorithm based on the position of the mobile terminals","authors":"S. Kyriazakos, D. Drakoulis, G. Karetsos","doi":"10.1109/SCVT.2000.923356","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923356","url":null,"abstract":"Position location of mobile terminals is expected to be one of the key services for mobile network operators in the near future. A variety of services may be offered, such as emergency-call assistance, fleet management, location-based value added services, navigation, stolen vehicle monitoring, improved network management and differential billing. Currently, network suppliers and research institutes worldwide are trying to conclude on the integration of positioning techniques, that fulfils related FCC and ETSI localization requirements, without exaggerating network costs. Furthermore, the rapidly increasing number of mobile subscribers in addition to the introduction of new circuit/packet-based data services, will cause serious traffic overload in cellular networks. Handover procedures use the signaling resources of the network and this is one of the system's parameters that has to be optimized. We propose an intelligent algorithm that makes use of the user's location to simplify the procedure and results in a stable system, decreasing the signaling congestion and the call-drop probability.","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"30 1","pages":"155-159"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81361575","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}
引用次数: 25
MIMO wireless for fixed broadband service 用于固定宽带服务的MIMO无线
教育传播与技术 Pub Date : 2000-10-19 DOI: 10.1109/SCVT.2000.923367
A. Paulraj
{"title":"MIMO wireless for fixed broadband service","authors":"A. Paulraj","doi":"10.1109/SCVT.2000.923367","DOIUrl":"https://doi.org/10.1109/SCVT.2000.923367","url":null,"abstract":"","PeriodicalId":58934,"journal":{"name":"教育传播与技术","volume":"11 1","pages":"263-297"},"PeriodicalIF":0.0,"publicationDate":"2000-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81656134","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}
引用次数: 0
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