Cluster Analysis of mobile communication network station location

With the rapid development of the digital new infrastructure industry, the energy demand for communication base stations in smart grid systems is escalating daily. The country is vigorously promoting the communication energy storage industry. However, the energy storage capacity of base stations is limited and widely distributed, making it difficult to effectively participate in power grid auxiliary services by only implementing the centralized control of base stations. Aiming at this issue, an interactive hybrid control mode between energy storage and the power system under the base station sleep control strategy is delved into in this paper. Grounded in the spatiotemporal traits of chemical energy storage and thermal energy storage, a virtual battery model for base stations is established and the scheduling potential of battery clusters in multiple scenarios is explored. Then, based on the time of use electricity price and user fitness indicators, with the maximum transmission signal and minimum operating cost as objective functions, a decentralized control device is used to locally and quickly regulate the communication system. Furthermore, a multi-objective joint peak shaving model for base stations is established, centrally controlling the energy storage system of the base station through a virtual battery management system. Finally, a simulation analysis was conducted on data from different types of base stations in the region, designing two distinct scheduling schemes for four regional categories. The analysis results demonstrate that the proposed model can effectively reduce the power consumption of base stations while mitigating the fluctuation of the power grid load.

In this work we investigate optimal geographical caching in heterogeneous cellular networks where different types of base stations (BSs) have different cache capacities. Users request files from a content library according to a known probability distribution. The performance metric is the total hit probability, which is the probability that a user at an arbitrary location in the plane will find the content that it requires in one of the BSs that it is covered by. We consider the problem of optimally placing content in all BSs jointly. As this problem is not convex, we provide a heuristic scheme by finding the optimal placement policy for one type of base station conditioned on the placement in all other types. We demonstrate that these individual optimization problems are convex and we provide an analytical solution. As an illustration, we find the optimal placement policy of the small base stations (SBSs) depending on the placement policy of the macro base stations (MBSs). We show how the hit probability evolves as the deployment density of the SBSs varies. We show that the heuristic of placing the most popular content in the MBSs is almost optimal after deploying the SBSs with optimal placement policies. Also, for the SBSs no such heuristic can be used; the optimal placement is significantly better than storing the most popular content. Finally, we show that solving the individual problems to find the optimal placement policies for different types of BSs iteratively, namely repeatedly updating the placement policies, does not improve the performance.

The continuously growing mobile traffic demand is pushing wireless networks to dense heterogeneous architectures with different types of base stations (BSs). In such dense heterogeneous networks (HetNets), especially in the high-rise building 3-D environment, the users need to determine which BS to be associated with before communication. Different user association schemes lead to different system performance. In this paper, a maximum instantaneous signal-to-interference-plus-noise ratio (MISINR) user association scheme is studied in the dense urban environment. A general 3-D model is utilized to model the dense urban HetNets deployed in the high-rise buildings. The coverage probability and average user rate are theoretically derived by using stochastic geometry in a general case and an interference-limited case, respectively. Numerical and simulation results demonstrate that the MISINR user association scheme has the best performance compared with other two association schemes in 3-D HetNets. From the results, it is interesting to observe that the expressions of coverage probability and average user rate can be simplified to closed-forms in the interference-limited case.

In order to support orders of traffic explosion with sustainable energy consumption, besides conventional Spectrum Efficiency (SE), Energy Efficiency (EE) is proposed as another critical metric for the next generation mobile networks (5G). This paper proposes to evaluate the potential EE gain of 5G on the basis of EARTH Energy Efficiency Evaluation Framework (E3F). As E3F indicated, the large-scale network traffic over the long term is definitely heterogeneous, which is still the trend in 5G. In this paper, relationship is deduced between the global EE metric and the snapshot EE metrics, which are obtained from small scale and short term. To be specific, this paper considers two typical 5G scenarios as different snapshots: the indoor office and the outdoor open space gathering. Each snapshot scenario has its own combinations of service/applications, hence distinct traffic model and resulted network deployment, power consumption and EE. The power model used for EE evaluation considers the different bandwidth and antenna configurations for different types of Base Stations (BSs) in different scenarios, meanwhile, it identifies the long term hardware evolution as a key factor to predict future power consumptions. Numerical analysis reveals that up to 1000x EE gain can be achieved by 5G and gain of hundreds times can be realized in 5G era, when 4G coexist with 5G.

During low traffic hours switching off the base stations is an effective way of saving energy in mobile communication network. To serve increased traffic and to fulfill large and high speed data demand, operators are deploying more number off base stations. This is leading to more energy consumption in the mobile communication network. So minimizing the energy consumption in the mobile communication has become a primary concern. In communication system maximum energy is consumed at the base stations. Hence by switching off some of the base stations at low traffic hours, energy can be saved. In this work we developed static and dynamic base station switch off methods to minimize the energy consumption during low traffic condition. Using this base station switch off methods we are able to save 12.63%, 10.81% and 12.66% of power for three different traffic scenarios.

We consider heterogeneous network (HetNet) systems comprising of two different types of base-stations (BSs): macro and small BSs. In the previous studies for HetNet, it is observed that the distribution of signal to interference plus noise ratio (SINR) is independent of the BS density. This implies that network throughput increases linearly with the number of BSs. In this paper, however, we have identified key practical factors which degrade the SINR distribution for dense HetNet. On the contrary to the previous studies, limited network throughput is verified by evaluating the areal capacity with respect to the density of BS under the practical channel model. The observation is made regardless of the deployment scenario whether the two types of BSs share the same frequency band or not. Based on the analysis and the simulation results provided in this paper, we present principal guidelines for cell deployment and system operation to improve the areal capacity of dense HetNet systems.

This paper investigates the capacity of the cooperative cellular networks and proposes to use the 2-D nested deployment on the base stations. Further analysis of sum-rate capacity and spectrum efficiency shows that this approach provides significant improvement. The study leverages the traditional model of regarding the coverage of base stations as the hexagonal blocks and views each hexagon as a macro-cell. One of the theoretical contributions of this paper is to use the invariance in the difference co-array to cover the derive the entire set of the channel fading coefficients. Furthermore, this paper proves the validity of using the average sum-rate capacity to calculate the capacity of the networks in both Rayleigh fading and non-fading channels. We also use simulations to confirm the correctness of the proposed theories from another perspective. As a result, the proposed approach remarkably improves the capacity of the network with the same amount of base stations.

The heterogeneous cellular network (HCN) is a promising technology to handle the rising number of devices due to their universal presence. This rising popularity HCN based Machine-to-Machine (M2M) communications is opening new opportunities and also bringing forth new system design issues. However, the main challenge of M2M communication is the possibility of huge traffic and significant difference in the nature of M2M traffic than the current commercial traffic for which current cellular network is designed and optimized. In this article, we investigate the uplink resource allocation problem of M2M devices (MDs) in the multiple Femto base station's coverage. We first model the uplink power and sub-carrier allocation in femtocells independently; Based on the cooperative game resource allocation among MDs is analyzed through non-transferable utility game to enhance the data rate performance with minimum utilization of power. Simulation results show that the resource allocation model based on cooperative game is able to provide a fair distribution of data rate compared with non-cooperative and greedy type of MDs.

Combine federated learning with the mobile network a good opportunity for the introduction of AI technology research and application in the mobile communication network.This article proposes a kind of the mobile network architecture based on FL to promote the integration of FL technologies with mobile communication network and to meet the joint modelling needs of users, operators, and industries. And points out some key technologies of the mobile network to illustrate how the mobile network to support FL working. Meanwhile, proposes some use cases to illustrate what possible application scenarios and values, if the FL technology is introduced into the mobile communication network.

The system capacity for future mobile communication needs to be increased to fulfill the emerging requirements of mobile services and innumerable applications. The cellular topology has for long been regarded as the most promising way to provide the required increase in capacity. However with the emerging densification of cell deployments, the traditional cellular structure limits the efficiency of the resource, and the coordination between different types of base stations is more complicated and entails heavy cost. Consequently, this study proposes frameless network architecture (FNA) to release the cell boundaries, enabling the topology needed to implement the FNA resource allocation strategy. This strategy is based on resource pooling incorporating a new resource dimension-antenna/antenna array. Within this architecture, an adaptive resource allocation method based on genetic algorithm is proposed to find the optimal solution for the multi-dimensional resource allocation problem. Maximum throughput and proportional fair resource allocation criteria are considered. The simulation results show that the proposed architecture and resource allocation method can achieve performance gains for both criteria with a relatively low complexity compared to existing schemes.

This paper provides an assessment of 3GPP standardized LTE/LTE-A uplink power control procedures in case of a co-channel operation of different types of base stations. Especially the case of femtocell deployment with an overlaying macrocell is considered. Imperfections of the currently accepted procedures in case of such networks are pointed and a modified solution is proposed. It is shown that in case of heterogeneous networks more cell-specific configuration can lead to 8% and 14% performance improvements in capacity and coverage of local cells respectively, without harm for overlying macrocells. The evaluation of the proposed scheme has been done on case of a macro and femto co-channel deployment, but should be also valid for other cell types.

The cell planning problem with capacity expansion is examined in wireless communications. The problem decides the location and capacity of each new base station to cover expanded and increased traffic demand. The objective is to minimize the cost of new base stations. The coverage by the new and existing base stations is constrained to satisfy a proper portion of traffic demands. The received signal power at the base station also has to meet the receiver sensitivity. The cell planning is formulated as an integer linear programming problem and solved by a tabu search algorithm. In the tabu search intensification by add and drop move is implemented by short-term memory embodied by two tabu lists. Diversification is designed to investigate proper capacities of new base stations and to restart the tabu search from new base station locations. Computational results show that the proposed tabu search is highly effective. A 10% cost reduction is obtained by the diversification strategies. The gap from the optimal solutions is approximately 1/spl sim/5% in problems that can be handled in appropriate time limits. The proposed tabu search also outperforms the parallel genetic algorithm. The cost reduction by the tabu search approaches 10/spl sim/20% in problems: with 2500 traffic demand areas (TDAs) in code division multiple access (CDMA).

This paper will discuss the distributed caching strategies in clustered heterogeneous cellular networks. Basically, there are two obstacles to accomplish the caching policy in the wireless access networks, i.e., the limited storage capacity of small cells and the too small coverage area of each base station to imply content aggregation effect. Traditionally, the existing caching strategies only concern the local requests within one base station coverage, which neglects the clustered characteristics of network infrastructure and user traffic demand. In this paper, we consider a two-tier clustered cellular networks, within which small cells can exchange content to fulfill each user request. Intuitively, this cooperation between base stations increases the service capacity of clustered cellular networks as testified in our numerical simulation.

This paper provides an analytical framework with foundations in stochastic geometry to characterize the spatio-temporal interference correlation as well as the joint coverage probability at two spatial locations in a cellular network. In particular, modeling the locations of cellular base stations (BSs) as a Poisson point process, we study interference correlation at two spatial locations $\ell _{1}$ and $\ell _{2}$ separated by a distance $v$ , when the user follows the closest BS association policy at both spatial locations and moves from $\ell _{1}$ to $\ell _{2}$ . With this user displacement, two scenarios can occur: i) the user is handed off to a new serving BS at $\ell _{2}$ , or ii) no handoff occurs and the user is served by the same BS at both locations. After providing intermediate results, such as probability of handoff and distance distributions of the serving BS at the two user locations, we use them to derive exact expressions for spatio-temporal interference correlation coefficient and joint coverage probability for any distance separation $v$ . We also study two different handoff strategies: i) handoff skipping , and ii) conventional handoffs , and derive the expressions of joint coverage probability for both strategies. The exact analysis is not straightforward and involves a careful treatment of the neighborhood of the two spatial locations and the resulting handoff scenarios. To provide analytical insights, we also provide easy-to-use expressions for two special cases: i) static user ( $v =0$ ) and ii) highly mobile user ( $v \rightarrow \infty )$ . As expected, our analysis shows that the interference correlation and joint coverage probability decrease with increasing $v$ , with $v \rightarrow \infty $ corresponding to a completely uncorrelated scenario. Further design insights are also provided by studying the effect of few network/channel parameters, such as BS density and path loss on the interference correlation.

In a Poisson Point Process (PPP) network model, in which the locations of Base Stations (BSs) are randomly distributed according to a Spatial Poisson Process, has been recently used as a tractable stochastic model to analyse the performance of downlink Heterogeneous Cellular Networks (HCNs). The HCN is modelled as a multi-tier cellular network where each tier is characterised by the transmission power level, propagation path loss exponent and density of BSs. The current works on HCN enabling Intercell Interference Coordination (ICIC) technique usually deal with Strict Frequency Reuse (FR) or Soft FR with a reuse factor of $\Delta=1$ in a Rayleigh fading channel. It has been assumed that all Base Stations (BSs) transmit continuously which leads to a reduction on the impact of number of users and RBs on network performance. In this paper, the performance of Soft FR with a reuse factor of $\Delta>1$ in Rayleigh-Lognormal fading channel is evaluated. The impact of the number of users and Resource Blocks (RBs) on Intercell Interference (ICI) are presented for Round Robin scheduling and indicator functions. The results show that there are opposite trends between coverage probability of Cell-Center User (CCU) and Cell-Edge User (CEU).