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In today's cellular networks, it becomes harder to provide the resources for the increasing and fluctuating traffic demand exactly in the place and at the time where and when they are needed. Moreover, a cellular network which can cover indoor areas and hot-spots is a complicated and expensive task. Therefore, a new hierarchical topology is put forward to solve the problem, and the topology have application...
In current cellular networks base stations (BSs) usually perform independent scheduling without coordinating the resource allocation among different cells. This, however, often leads to high interference levels in cellular networks operating with universal frequency reuse, such as the 3GPP UTRAN Long Term Evolution (LTE). Coordinated scheduling between different BSs may mitigate this problem by taking...
The race toward higher throughputs for cellular network users is getting more difficult everyday. On the one hand cellular network operators wish to increase benefits by offering new services to users, but on the other hand spare radio resource are shrinking away. The spreading of WiFi-3G dual mode devices is making this fight even harder. The new ”Femtocell” technology is expected to be the rescuer...
In GERAN networks, Multiple Users Reusing One Single timeslot (MUROS) promises to enhance the cell capacity through pairing of two or more users onto a single timeslot. So far no work has been done on the basis on which the different users would be paired. The criteria used for the pairing decision to pair two or more users is critical for MUROS as this will eventually decide the actual gains due...
Current cellular systems suffer from co-channel interference, when simultaneous transmissions in other cells use the same physical resources. Schemes involving cooperation between Base Stations (BS) are currently discussed for further releases of the 3GPP Long Term Evolution (LTE) system as a promising method to mitigate co-channel interference for users located at cell-edge. The BS cooperation approach...
This paper studies the different ways of extending wireless coverage for high data rates and improving the data capacity in a building. The solutions considered include deployments of single or multiple small base stations, i.e. Picocell or Femtocell, and distributed antenna system, operated on the same frequency as the macro cellular network. We look at the radio performance of each solution in a...
This paper discusses the use of high altitude platforms, HAPs, to provide mobile communication services to on-ground customers. The paper explains the behavior of UMTS radio network in a situation, where the service is being provided by HAP and terrestrial base stations in a disaster scenario. In the disaster scenario, a set of adjacent terrestrial cellular base stations in the middle of the network...
Incorporating relay nodes in cellular networks, e.g. UMTS/ HSPA, is beneficial for extending coverage as well as for service enhancement. In this paper we study the inter-cell interference generated by a relay-enabled cell and how this influences the performance of mobile users. The performance measures of interest are the inter-cell interference distribution, realized rates and flow throughput. Our...
Coordinated Multipoint (CoMP) transmission techniques have been considered as tools to improve cell-edge and average data throughput for LTE-Advanced. First investigations of CoMP techniques in homogeneous hexagonal macro layouts have shown that interference coordination needs to involve dominant interferers to allow significant gain. Therefore, in the present paper the application of CoMP in a heterogeneous...
In this paper the impact of the overlay of CDMA2000 1x-EVDO and CDMA2000 cellular systems in terms of throughput is investigated. Currently, the 3G cellular systems furthermore to provide only voice services are focusing to offer a variety of data applications such as VoIP, video, telephony, wireless gaming, and push-to-talk (PTT), along with a high demand of downlink intensive applications. The result...
In this paper we analyze the performance of the UMTS Enhanced Uplink (EUL) in a network scenario, under various packet scheduling schemes. Besides the impact of the intrinsic differences of the scheduling schemes on EUL performance (which we studied in a previous paper for a single cell scenario), we are particularly interested in how the different scheduling schemes influence EUL performance through...
The target of this paper is to investigate different traffic handling strategies to increase the capacity of the network. Impact of deploying UMTS900 with other GSM900/1800 and UMTS2100 layer was also observed in terms of capacity of the network. Number of mobile users is increasing enormously, and it is expected that the demand for data services and different kind of multimedia services will grow...
Nowadays cellular systems operate with frequency reuse one, where adjacent cells use the same frequency band. Use equipments (UEs) located at cell edge are mostly affected by the resulting co-channel interference. In addition, cell edge UEs suffer from their weak carrier signal strength. This paper proposes a new method to increase the performance of cell edge UEs by means of information exchange...
In this paper, we evaluate analytically the capacity gain if we use the HSDPA system in band VIII. This work is based on a statistical approach that calculates the cell capacity knowing the throughput at each distance to the base station. This throughput is obtained by thorough simulations that take into account the propagation, environment (urban/rural, indoor/outdoor) and different mobile categories...
Third generation (3G) cellular networks are being implemented in many countries at high rate. Due to the fact that manual cell planning is a time consuming process and prone to a degree of error and inefficiency, there is a need for automated approaches to optimise coverage, capacity and quality of cellular networks in a fraction of the time. This paper studies the application of genetic algorithms...
This paper describes concretely the assessment of the GSM900 Base station transmission influence on UMTS900 Equipment receiver in coordinated deployment case according to some spectral masks in reception. This work is based on theoretical approaches which quantify the GSM interference level and shows the filter importance in coexistence issues between UMTS900 and GSM900. In order to minimize the GSM...
This paper solves the joint power control and SIR assignment problem through distributed algorithms in the uplink of multi-cellular wireless networks. The 1993 Foschini-Miljanic distributed power control can attain a given fixed and feasible SIR target. In data networks, however, SIR needs to be jointly optimized with transmit powers in wireless data networks. In the vast research literature since...
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