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1.
The capacity and the interference statistics of the sectors of the shaped W-CDMA cell are studied. A model of five cells is used to analyze the uplink. The cells are assumed to exist in rural zones. The capacity and the interference statistics of the cell are studied using a two-slope propagation model. The expected value and the variance of the interference are given for different propagation exponent 相似文献
2.
The capacity and the interference statistics (mean value and variance) of the sectors of the cigar-shaped Wideband Code Division
Multiple Access microcells are studied. The two-slope propagation model is used in the analysis. A model of five microcells
is used to calculate the uplink capacity and interference statistics assuming highways cigar-shaped microcells. The capacity
and the interference statistics of the microcell are studied for different sector range, propagation exponent, antenna side
lobe levels and different standard deviation of the power control error. It is noticed that the quasi-maximum uplink sector
capacity can be got when the sector range R is between 600 and 1,200 m and the sidelobe level of the directive antenna used
in each sector is on the order of −15 dB. 相似文献
3.
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.
Jarkko Kaleva Petri Komulainen Markku Juntti Antti Tölli 《Wireless Personal Communications》2013,71(3):1649-1662
In this work, the effect of the multipath on the capacity and the interference statistics of the sectors of the highways cigar-shaped W-CDMA microcells is studied. A model of five microcells is used to analyze the uplink. The capacity and the interference statistics of the microcell are studied for different antenna sidelobe levels and different sector ranges. In the study, imperfect power control and limited transmitted power are assumed. Users are assumed to be within equally spaced buses and cars. The uplink capacity of the sector is studied assuming three types of services, namely, voice, 3G data and 3.75G data (representing the High Speed Uplink Packet Access). It is shown that, the sector uplink capacity depends on the buses and cars density within the sector. The capacity is also given as a function of the number of buses and cars within the sector. 相似文献
5.
The capacity and the interference statistics of the sectors of the shaped Wideband Code Division Multiple Access (W-CDMA)
microcells serving over-ground trains are studied. A model of five microcells is used to analyze the uplink. The capacity
and the interference statistics of the microcell are studied for different antenna sidelobe levels and different sector ranges.
In the study, imperfect power control and limited transmitted power are assumed. The effect of the power assigned to the uplink
pilot is taken into account. It is shown that, the sector capacity depends on the train’s position. The uplink sector capacity
limits (upper and lower) are presented. The lower capacity limit is given as a function of the sector range and the sidelobe
level of the directive antenna used in each sector. 相似文献
6.
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
7.
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: |
8.
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
9.
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
10.
In this work, the capacity and the interference statistics of the uplink of high-altitude platforms (HAPs) for asynchronous and synchronous WCDMA system assuming finite transmission power and imperfect power control are studied. Propagation loss used to calculate the received signal power is due to the distance, shadowing, and wall insertion loss. The uplink capacity for 3- and 3.75-G services is given for different cell radius assuming outdoor and indoor voice users only, data users only and a combination of the two services. For 37 macrocells HAP, the total uplink capacity is 3,034 outdoor voice users or 444 outdoor data users. When one or more than one user is an indoor user, the uplink capacity is 2,923 voice users or 444 data users when the walls entry loss is 10?dB. It is shown that the effect of the adjacent channels interference is very small. 相似文献
11.
This article estimates the reverse link capacity of an SIR-based power-controlled code-division multiple access system in a multiple cells environment. The effect of multipath fading on the interference statistics is explicitly accounted for and mobiles are assumed to connect to a base station based on minimum attenuation criterion. 相似文献
12.
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: |
13.
基于虚拟无线电通信仿真平台的中频噪声调幅干扰的抑制 总被引:1,自引:0,他引:1
基于虚拟无线电仿真平台,对中频噪声调幅干扰的统计特性进行理论分析,并对实验干扰数据进行统计特性估计,在此基础上进一步研究了语音中频段抗干扰算法。 相似文献
14.
Power control (PC) on the reverse link of a direct-sequence code-division multiple-access system is essential to increase system capacity. Perfect PC eliminates fluctuations in the received signal level and hence reduces the required signal-to-interference ratio. However, a perfect PC algorithm tracks multipath fading accurately, which results in increasing the intercell interference level. A fixed step PC algorithm becomes almost perfect when the power command rate is too fast compared to the Doppler rate, which is the case for low-mobility users. We investigate the statistics of the intercell interference assuming users are moving slowly. These statistics are then used to find the system capacity. Three parameters that can affect the capacity are considered: the number of the fading process resolvable paths, the maximum transmitted power, and soft handoff 相似文献
15.
The multiservice (voice, data, and high-speed uplink packet access (HSUPA)) uplink capacity and the interference statistics of high-altitude platforms wideband code-division multiple access macrocell are studied. The free-space propagation loss model with a log-normal shadowing is used in the analysis. It is concluded that the voice and data service are significantly affected by HSUPA users and that the macrocell capacity decreases dramatically when one of these users gets connected to it in the case that they share the same frequency band. Also, it is concluded that the capacity decrement is highly sensitive to the location of the HSUPA users. When the HSUPA users did not share the same frequency band with the voice and traditional data users, macrocell capacity will be 3 HSUPA users with a processing gain of 8 or 5.3 HSUPA users with a processing gain of 16. 相似文献
16.
17.
Duk Kyung Kim Dan Keun Sung 《Vehicular Technology, IEEE Transactions on》2001,50(3):701-710
Capacity estimation in code division multiple access (CDMA) systems is an important issue which is closely related to power control. Strength-based power control has been assumed in most analyses in which other cell interference was considered as a known and fixed variable. However, in signal-to-interference ratio (SIR)-based power-control systems, power control and other cell interference are closely related to each other and capacity can be obtained by considering this relationship. This study derives the reverse-link capacity of an SIR-based power-controlled multicode CDMA system supporting heterogeneous CBR and on-off traffic in a multiple cell environment. Mean and variance statistics of total other cell interference, and the effects of traffic and propagation parameters on system capacity are investigated 相似文献
18.
A CDMA uplink system that carries both voice and data traffic is investigated. The reservation-based admission control scheme is used to prioritize voice mobiles, and the truncated channel inversion power control scheme is used by data mobiles to improve system capacity. The performance of the system is measured by the Erlang capacity. Two methods of determining the Erlang capacity are presented. The first method decouples the analysis of blocking and outage performance, thus simplifying numerical search. The second method takes into account the impact of mobile traffic fluctuations on interference statistics, and thus yields more accurate results. Numerical results are provided that show significant differences between the two methods. Finally, the Erlang capacities of the system are compared for different power control schemes. 相似文献
19.
The authors present a summary of the results of a study on CDMA feedback power control in multipath fading radio channels. The signal and interference statistics after power control are presented for a simulated radio system which includes multiple base stations. It is shown that often used analyses based on perfect average power control lead to optimistic capacity results because interference is underestimated by 1-2 dB.<> 相似文献