Capacity Limits of Base Station Cooperation in Cellular Networks

2010 ◽  
pp. 102-132
Author(s):  
Symeon Chatzinotas ◽  
Muhammad Ali Imran ◽  
Reza Hoshyar
Keyword(s):  
Channel Model ◽  
High Capacity ◽  
Path Loss ◽  
Base Station ◽  
Cellular Systems ◽  
Current Channel ◽  
Capacity Limits ◽  
Base Station Cooperation ◽  
Rate Capacity ◽  
Sum Rate

In the information-theoretic literature, it has been widely shown that multicell processing is able to provide high capacity gains in the context of cellular systems. What is more, it has been proved that the per-cell sum-rate capacity of multicell processing systems grows linearly with the number of base station (BS) receive antennas. However, the majority of results in this area have been produced assuming that the fading coefficients of the MIMO subchannels are completely uncorrelated. In this direction, this chapter investigates the ergodic per-cell sum-rate capacity of the Gaussian MIMO cellular channel under correlated fading and BS cooperation (multicell processing). More specifically, the current channel model considers Rayleigh fading, uniformly distributed user terminals (UTs) over a planar cellular system, and power-law path loss. Furthermore, both BSs and UTs are equipped with correlated multiple antennas, which are modelled according to the Kronecker product correlation model. The per-cell sum-rate capacity is evaluated while varying the cell density of the system, as well as the level of receive and transmit correlation. In this context, it is shown that the capacity performance is compromised by correlation at the BS-side, whereas correlation at the UT-side has a negligible effect on the system’s capacity.

scholarly journals Sum Rate Analysis of MU-MIMO with a 3D MIMO Base Station Exploiting Elevation Features

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Xingwang Li ◽  
Lihua Li ◽  
Fupeng Wen ◽  
Junfeng Wang ◽  
Chao Deng
Keyword(s):  
Channel Model ◽  
Mimo Systems ◽  
Multiple Input Multiple Output ◽  
Three Dimensional ◽  
Base Station ◽  
Rate Performance ◽  
High Rise ◽  
Rate Analysis ◽  
Input Multiple Output ◽  
Sum Rate

Although the three-dimensional (3D) channel model considering the elevation factor has been used to analyze the performance of multiuser multiple-input multiple-output (MU-MIMO) systems, less attention is paid to the effect of the elevation variation. In this paper, we elaborate the sum rate of MU-MIMO systems with a 3D base station (BS) exploiting different elevations. To illustrate clearly, we consider a high-rise building scenario. Due to the floor height, each floor corresponds to an elevation. Therefore, we can analyze the sum rate performance for each floor and discuss its effect on the performance of the whole building. This work can be seen as the first attempt to analyze the sum rate performance for high-rise buildings in modern city and used as a reference for infrastructure.

On the Capacity of MIMO Cellular Systems with Base Station Cooperation

2011 ◽  
Vol 10 (11) ◽  
pp. 3720-3731 ◽  
Author(s):  
Peng Wang ◽  
Hao Wang ◽  
Li Ping ◽  
Xiaokang Lin
Keyword(s):  
Base Station ◽  
Cellular Systems ◽  
Base Station Cooperation

scholarly journals Sum Rate Analysis for Massive MIMO Downlink With MRC Beamforming and User Selection

2021 ◽  
Vol 2113 (1) ◽  
pp. 012025
Author(s):  
Yiyang Wu ◽  
Chang Chang ◽  
Fei Xie ◽  
Dacheng Ju ◽  
Yilun Pan
Keyword(s):  
Channel Model ◽  
Base Station ◽  
Transmission Model ◽  
User Selection ◽  
Selection Algorithm ◽  
User Scheduling ◽  
Downlink System ◽  
Sum Rate ◽  
Simulation Results ◽  
Mimo Downlink

Abstract Average allocation of data rate to each user is inefficient since the resource a base station can allocate is limited. Thus, user selection and user scheduling need to be applied into multi-user massive multiple-input multiple-output (MIMO) downlink system. In this paper, we mainly focus on the methods of user selection. First, we establish a downlink system model including transmission model and channel model. Then, two user-rate based user selection algorithms via the signal-to-interference-plus-noise-ratio (SINR) are proposed, where the SINR is generated by MRC beamforming. Finally, simulation results are provided to compare the performance of two proposed algorithms and their fairness towards selected users. In the simulation results, location-based selection algorithm and random selection algorithm are jointly compared. The second proposed algorithm possesses the highest total sum-rate and is the optimal algorithms among the four algorithms.

scholarly journals Channel Propagation Characteristics on the Performance of 4G Cellular Systems from High Altitude Platforms (HAPs)

2021 ◽  
Vol 13 (3) ◽  
Author(s):  
Kabiru Yusuf ◽  
Dahiru Sani Shuaibu ◽  
Suleiman Aliyu Babale
Keyword(s):  
High Altitude ◽  
Channel Model ◽  
Elevation Angle ◽  
Base Station ◽  
Cellular Systems ◽  
Frequency Variation ◽  
Propagation Characteristics ◽  
Technical Limitation ◽  
Proposed Model ◽  
High Altitude Platforms

In this paper, we investigated the effect of different channel propagation characteristics on the performance of 4G systems from high altitude platforms (HAPs). The use of High-Altitude Platforms for communication purpose in the past focused mostly on the assumption that the platform is quasi stationary. The technical limitation of the assumption was that of ensuring stability in the positioning of the platform in space. The use of antenna steering and other approaches were proposed as a solution to the said problem. In this paper, we proposed a channel model which account for the motion of the platform. This was done by investigating the effect of Doppler shift on the carrier frequency as the signals propagate between the transmitter and receiver while the High-Altitude Platform is in motion. The basic free space model was used and subjected to the frequency variation caused by the continuous random shift due to the motion of the HAPs. The trajectory path greatly affects the system performance. A trajectory of 30km, 100km and 500km radii were simulated. An acute elevation angle was used in the simulation. The proposed model was also compared to two other channel models to illustrate its performance. The results show that the proposed model behave similar to the existing models except at base station ID 35 and 45 where the highest deviation of 20dBm was observed. Other stations that deviated were less than 2dBm.

scholarly journals Low-Complexity User Scheduling with Switched Tilting for 3D Cellular Systems

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Haijing Liu ◽  
Hui Gao ◽  
Tiejun Lv
Keyword(s):  
Large Scale ◽  
Matrix Theory ◽  
Low Complexity ◽  
Base Station ◽  
Optimal Number ◽  
Cellular Systems ◽  
Rate Performance ◽  
User Scheduling ◽  
Sum Rate ◽  
Computational Resources

We propose a low-complexity user scheduling scheme to enhance the sum rate performance for a multicell downlink system, in which the base station (BS) is equipped with a large-scale active antenna array. First, we divide each cell intoNregions according to the vertical beamwidth of the BS antennas. Next, candidate user equipment (UE) items are assigned to corresponding groups to their locations. Each scheduling slot is also divided intoNequal-time subslots. Then, at each subslot, we focus on one UE group, select the optimal number,K*, of UEs for simultaneous data transmission in the manner of round-robin scheduling, and adjust the BS antenna tilting to the optimal angleθtilt*. In particular,K*andθtilt*for each UE group are both obtained by means of large-system asymptotic analysis. Benefiting from the random matrix theory tools, the asymptotic analytical results are independent of instantaneous channel state information of UE, which make it possible to solveK*andθtilt*offline, therefore saving the online computational resources significantly. Numerical results verify that the proposed scheme achieves good sum rate performance with extremely low computational complexity.

scholarly journals Sum-Rate Channel Capacity for Line-of-Sight Models

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1674
Author(s):  
Claudio Ferreira Dias ◽  
Felipe A. P. de Figueiredo ◽  
Eduardo Rodrigues de Lima ◽  
Gustavo Fraidenraich
Keyword(s):  
Series Expansion ◽  
Channel Capacity ◽  
Mathematical Problem ◽  
Joint Probability ◽  
Exact Expression ◽  
Base Station ◽  
Line Of Sight ◽  
Rate Capacity ◽  
The Mean ◽  
Sum Rate

This work considers a base station equipped with an M-antenna uniform linear array and L users under line-of-sight conditions. As a result, one can derive an exact series expansion necessary to calculate the mean sum-rate channel capacity. This scenario leads to a mathematical problem where the joint probability density function (JPDF) of the eigenvalues of a Vandermonde matrix WWH are necessary, where W is the channel matrix. However, differently from the channel Rayleigh distributed, this joint PDF is not known in the literature. To circumvent this problem, we employ Taylor’s series expansion and present a result where the moments of mn are computed. To calculate this quantity, we resort to the integer partition theory and present an exact expression for mn. Furthermore, we also find an upper bound for the mean sum-rate capacity through Jensen’s inequality. All the results were validated by Monte Carlo numerical simulation.

scholarly journals Performance Analysis of 3D Massive MIMO Cellular Systems with Collaborative Base Station

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Xingwang Li ◽  
Lihua Li ◽  
Ling Xie ◽  
Xin Su ◽  
Ping Zhang
Keyword(s):  
Lower Bound ◽  
Massive Mimo ◽  
Mimo Systems ◽  
Mimo System ◽  
Base Station ◽  
Cellular Systems ◽  
Small Scale ◽  
Pilot Contamination ◽  
3D Mimo ◽  
Sum Rate

Massive MIMO have drawn considerable attention as they enable significant capacity and coverage improvement in wireless cellular network. However, pilot contamination is a great challenge in massive MIMO systems. Under this circumstance, cooperation and three-dimensional (3D) MIMO are emerging technologies to eliminate the pilot contamination and to enhance the performance relative to the traditional interference-limited implementations. Motivated by this, we investigate the achievable sum rate performance of MIMO systems in the uplink employing cooperative base station (BS) and 3D MIMO systems. In our model, we consider the effects of both large-scale and small-scale fading, as well as the spatial correlation and indoor-to-outdoor high-rise propagation environment. In particular, we investigate the cooperative communication model based on 3D MIMO and propose a closed-form lower bound on the sum rate. Utilizing this bound, we pursue a “large-system” analysis and provide the asymptotic expression when the number of antennas at the BS grows large, and when the numbers of antennas at transceiver grow large with a fixed ratio. We demonstrate that the lower bound is very tight and becomes exact in the massive MIMO system limits. Finally, under the sum rate maximization condition, we derive the optimal number of UTs to be served.

Sign in / Sign up

Export Citation Format

Share Document