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1.
The multi-service (voice, data and HSUPA) uplink capacity and the interference statistics of the sectors of the cigar-shaped WCDMA microcell are studied using a model of 5 highway microcells. The two-slope propagation loss model with lognormal shadowing is used in the analysis. It is concluded that the voice and data service are significantly affected by HSUPA users and sector capacity decreases dramatically when one of these users gets connected to a given sector or to one next to it. Also it has been concluded that the capacity decrement is highly sensitive to the location of the HSUPA users. Thus, no more than one HSUPA with a process gain of 16 can be connected to a given base station. In this case, the HSUPA user should interrupt its transmission when it is near to the sector border. No more than one HSUPA user with a process gain of 8 is permitted in a given sector and the sector next to it. When the HSUPA user is at the sector border, its transmission should be disabled. 相似文献
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Taha Ahmed Bazil Calvo Ramón Miguel De Haro Ariet Leandro 《International Journal of Wireless Information Networks》2004,11(1):55-62
The capacity and the interference statistics of the sectors of the cross-shaped W-CDMA cell are studied using an analytical approach. A model of 49 cells is used to analyse the uplink, which limits the capacity. The cells are assumed to exist in rural zones. The capacity and the interference statistics of the microcell are studied for different sector ranges and different antenna sidelobe levels. 相似文献
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Bazil Taha-Ahmed Miguel Calvo-Ramón Leandro Haro-Ariet 《Wireless Personal Communications》2007,41(1):43-55
The capacity and the interference statistics of the sectors of the cigar-shaped W-CDMA microcell are studied. A model of 5
microcells is used to analyze the uplink. The microcells are assumed to exist in rural zones. The capacity and the interference
statistics of the microcell are studied for different sector range, different antenna side lobe levels, different values of
the break point distance, different values of the propagation parameter s
2 and different standard deviation of the power control error. 相似文献
4.
Bazil Taha-Ahmed Miguel Calvo-Ramón Leandro Haro-Ariet 《Wireless Personal Communications》2007,43(2):295-311
The capacity and the interference statistics (mean and variance) of the sectors of a Cigar-, Tee-, and Cross-shaped WCDMA
microcells are studied. Models of 5, 7, and 9 microcells are used to analyze the uplink capacity of the cigar-, Tee-, and
cross-shaped W-CDMA microcell, respectively. The capacity and the interference statistics of the microcell are studied for
different sector range and antenna side lobe levels. It is shown that the highest sector capacity is obtained when the microcell
is cigar-shaped. For a cross-shaped microcell, the sector capacity is the lowest. Also it is shown that the uplink sector
capacity will be very high if synchronous WCDMA is used in the uplink. To get the quasi maximum capacity, the sector range
should be (0.6 – 1) km and the side lobe level of the directive antenna used in each sector should be – 15 dBc or lower. 相似文献
5.
Bazil Taha-Ahmed 《Wireless Personal Communications》2008,46(2):233-246
The multi-service (combination of more than one service) capacity and interference statistics (mean and variance) of the sectors
of the street cross-shaped Wide Band Code Division Access (WCDMA) microcell are studied. A model of 21 cross-shaped microcells
is used to analyze the uplink. The two slope propagation model is used to analyze the uplink. The capacity and interference
statistics of the sectors are studied for different sector ranges, side lobe levels and power control (PC) standard deviation
errors. It is noticed that, increasing the sector range will increase the sector capacity, reducing the side lobe level will
also increase the sector capacity. Also it is noticed that, increasing the propagation exponent s
2 will increase the sector capacity, reducing the standard deviations of the shadowing parameters σ1 and σ2 will increase the sector capacity and that reducing the power control standard deviation error σc will increase the sector capacity.
相似文献
Bazil Taha-AhmedEmail: |
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介绍了WCDMA系统中软切换模型,并在此基础上深入分析了下行容量影响因素,和软切换在下行链路容量的影响,推导出下行容量计算公式,为进一步研究和仿真WCDMA下行容量提供理论基础。 相似文献
8.
Heiska Kari Posti Harri Muszynski Peter Rautiainen Terhi Numminen Jussi 《Wireless Personal Communications》2002,23(2):217-242
This paper determines the coverage reduction of the Wideband CDMA (WCDMA) downlink in the case of interference, due to adjacent narrowband system. The coverage reduction has been evaluated in terms of blocking area around the interfering base station. The analysis takes into account different interference mechanisms and their individual effects to the coverage. The interference mechanisms which have been considered here are the out-of-band emissions of the base station transmitter, the adjacent channel interference due to non-ideal sideband filtering, the intermodulation and the crossmodulation. The coverage effects in realistic network environment have been computed by using accurate ray-tracing propagation models designed for the path loss calculation in the urban environment. In the numerical examples, the effect of GSM interference has been demonstrated, but the method can be utilized with other narrowband systems as well. The results can be utilized in radio system design, radio network planning (RNP) and the frequency allocation of the WCDMA systems. 相似文献
9.
Bazil Taha-Ahmed Miguel Calvo-Ramón Leandro de Haro-Ariet 《International Journal of Wireless Information Networks》2008,15(2):90-97
In this paper, the capacity and the interference statistics of the sectors of the cigar-shaped WCDMA microcells are studied
using the hybrid model of propagation. A model of nine microcells in a metro tunnel is used to analyze the uplink capacity
and the interference statistics. The capacity and the interference statistics of the microcells in metro tunnels are studied
in this work for different propagation parameters, antenna side lobe levels, sector ranges and bends losses.
相似文献
Bazil Taha-AhmedEmail: |
10.
WCDMA 软切换门限对下行容量的影响 总被引:1,自引:0,他引:1
本文分析了WCDMA下行容量与软切换门限之间的关系,得出在不同系统负载下,通过动态改变软切换门限可以优化系统性能的结论. 相似文献
11.
Bazil Taha Ahmed Miguel Calvo Ramón Leandro De Haro Ariet 《Wireless Personal Communications》2004,31(1):19-31
The uplink capacity and the interference statistics (mean and variance) of the sectors of the cigar-shaped W-CDMA microcell are studied. A model with eighteen sectors is used to analyze the uplink. The microcells are assumed to exist in a long tunnel with at least nine base stations. The hybrid model of propagation is used in the calculations. The capacity and the interference statistics of the sectors are studied in terms of the most important parameters: sector radius, specific attenuation factor, antenna sidelobe levels, bend losses and the power control standard deviation error. 相似文献
12.
The uplink capacity and the interference statistics (mean and variance) of the sectors of the cigar-shaped W-CDMA microcell are studied. A model with eighteen sectors is used to analyze the uplink. The microcells are assumed to exist in a long tunnel with at least nine base stations. The hybrid model of propagation is used in the calculations. The capacity and the interference statistics of the sectors are studied in terms of the most important parameters: sector radius, specific attenuation factor, antenna sidelobe levels, bend losses and the power control standard deviation error. 相似文献
13.
In this work, the multiservice uplink capacity of single and multiple femtocells is given. The COST231 multiwall and multifloor indoor propagation model has been used to calculate the indoor propagation loss. Results show that the uplink capacity of a deployed femtocell will reduce by 2 % if two extra femtocells are deployed in the same building higher and lower of it. Results also show that the uplink capacity is slightly affected if there are several femtocells deployed in the buildings around the one at which the femtocell under study is already exists. It is demonstrated that uplink capacity is interference limited if the femtocell is deployed to serve the users in three floors. Results show that the uplink capacity will be interference and noise limited if the femtocell is deployed to serve the users in five floors. Finally, it is found that the effect of the interference due to the uniformly distributed users within the macrocell around the femtocell is insignificant. 相似文献
14.
In this paper, the performance of turbo coding in WCDMA downlink is considered in conjunction with receivers using two adaptive
channel equalizers. Bit error and frame error rates are compared to the performance of the conventional Rake receiver. Special
consideration is given to the cases with two receive antennas, the efficiency of the channel interleaver, the number of iterations
in decoding, the performance with various numbers of users, the influence of mobile receiver velocity as well as to the effect
of power control. The simulation results show that turbo coding, combined with power control and channel equalizers is a very
efficient way to implement reliable data transmissions in WCDMA downlink. The results in the paper also verify that the adaptive
channel equalizers is a very promising technique to improve the receiver performance and increase the user capacity. 相似文献
15.
Interference performance is among the most important issues especially in WCDMA cellular networks planning coverage and capacity.
F-factor has been introduced in previous works to model the interference in WCDMA downlink dimensioning process. In this paper, we
establish its PDF expression assuming one interferer in the serving cell both with and without correlated shadowing effect.
Uniform and non-uniform traffic situations are distinguished through the study of both uniform and non-uniform traffic load
cases. Then, we generalize the expression for multiple interfering cell tiers. We show the impact of this evaluation on the
design process in order to increase the capacity of a network.
Anis Masmoudi received his Engineering diploma in 1999 from Sup'Com (Ecole Supérieure des Communications de Tunis: High Communication School of Tunis) then graduated in 2001 with Master of Science from Ecole Nationale d'Ingénieurs de Tunis (ENIT). He worked in 2000–03 as a research engineer in Centre d'Etudes et de Recherches des Télécommunications (CERT), then he is recruited in 2003 by Institut National des Sciences et de Technologie (INSAT) as a teacher assistant. His PHD research work is focused on mobile cellular networks planning, WCDMA / HSDPA dimensioning
processes and 3G networks optimisation in cooperation with Institut National des Télécommunications d'Evry -France (INT).
Sami Tabbane is Professor at Ecole Supérieure des Communications de Tunis (Sup'Com). He has graduated from Ecole des Mines de Paris in 1988 and got a PhD of Ecole Nationale Supérieure des Télécommunications de Paris (ENST) in 1991. He started his carreer at Centre National d'Etudes des Télécommunications (CNET) in Issy les Moulineaux in 1992–94 and was recruited by Sup'Com in 1994. His main research areas are: mobility management
(handover and location management), cellular networks planning and service implementation and optimization in 3G networks.
He is the co-author of “Réseaux GSM” (Hermes, 1995) and “Ingénierie des Services de Télécommunications” (Hermes-Lavoisier, 2005). He is the author of “Réseaux Mobiles” (Hermes, 1997), “Handbook of Mobile Networks” (Artech House, 2000), “Ingénierie des Réseaux Cellulaires” (Hermes-Lavoisier, 2002). 相似文献
16.
发射功率控制是CDMA系统的关键技术之一。在WCDMA的软切换中,传统下行链路功率控制方案的实现主要存在两个问题:基站发射功率的失衡和下行链路干扰的增大。为解决上述问题,本介绍三种新的下行功率控制方案:降低TPC频率功率控制、调整环功率控制和站选择分集发射功率控制。其中前两种方案用于恢复软切换中基站发射功率的平衡,而最后一种方案用于减小下行链路干扰。研究表明,利用上述方案能够有效减小软切换中基站发射功率的差异或下行链路干扰,从而提高了系统容量。 相似文献
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WCDMA系统采用独特的信道编码复用方案支持多媒体业务的传输,较好地实现对具有不同速率和QoS要求的各种业务的承载,然而也大大增加了系统的复杂度,并引入了长的处理时延。文章针对WCDMA技术规范,采用基于地址映射的搬移算法,用较少的硬件资源和较短的处理时延,实现了下行链路的解复用。 相似文献