In this work, we adopt the analysis of a heterogeneous cellular network by means of stochastic geometry, to estimate energy and spectral network efficiency. More specifically, it has been the widely spread experience that practical field assessment of the Signal-to-Noise and Interference Ratio (SINR), being the key physical-layer performance indicator, involves quite sophisticated test instrumentation that is not always available outside the lab environment. So, in this regard, we present here a simpler test model coming out of the much easier-to-measure Bit Error Rate (BER), as the latter can deteriorate due to various impairments regarded here as equivalent with additive white Gaussian noise (AWGN) abstracting (in terms of equal BER degradation) any actual non-AWGN impairment. We validated the derived analytical model for heterogeneous two-tier networks by means of an ns3 simulator, as it provided the test results that fit well to the analytically estimated corresponding ones, both indicating that small cells enable better energy and spectral efficiencies than the larger-cell networks.

In this paper, we analyze an arbitrary heterogeneous cellular network applying stochastic geometry, and propose a modified model for assessing network spectral and energy efficiency. With this regard, we recognize that, in practice, determining Signal-to-Noise-and-Interference Ratio (SINR) as the key performance indicator, requires complex field test equipment, which might not be available or affordable. Therefore, we propose here a simple model that is based on the relatively easy measurable Bit-Error Rate (BER), whose degradation caused by various impairments is considered here as if it was due to the according additive white Gaussian noise (AWGN), thus abstracting any specific non-AWGN distortion. The proposed analytical model is verified by ns3 software network simulator, whose test results are found to match the corresponding estimated values. This indicates that both spectral and energy efficiencies of small-cell networks are higher than in larger-cell networks, even more for heterogeneous two-tier networks.

For quite a while, it has been evident that homogeneous network architectures, based on cells with a uniform radiation pattern, cannot fulfill the ever increasing demand of mobile users for capacity and service quality while still preserving spectrum and energy. However, only with the introduction of the Fourth Generation mobile communication networks to deal with the surging data traffic of multimedia applications, have smaller cells been widely used to break down service zone areas of macro base stations into multiple tiers, thus improving network performance, reducing traffic congestion, and enabling better management of spectrum and energy consumption in a macro network. In this paper, we present an analytical model for assessing the efficiency of bandwidth and energy usage, as well as of network deployment, taking into account overall network investment and maintenance costs. This paves the way to the improved planning of network coverage, and its capacity and reliability, thus preserving its spectrum and energy, as well as the environment. The analysis considers the downlink of an arbitrary heterogeneous cellular network by using tools of stochastic geometry that adopt the distribution of base stations in the form of a Poisson Point Process. The proposed analytical model is verified by the according software simulations using the ns-3 network simulator. The obtained results closely match the theoretically predicted values and boundaries, clearly indicating that, in all three analyzed aspects: spectral, energy, and deploymental, the efficiency of small-cell networks was higher with respect to traditional large-cell networks and increased even further for heterogeneous (two-tier in our tests) networks.

The main OFDM drawbacks are Carrier Frequency Offset (CFO) and large Peak-to-Average Power Ratio (PAPR), which both degrade the Bit Error Rate (BER). Specifically, we consider here clipping or any other PAPR reduction method sufficient to prevent the nonlinear high-power amplifier from generating errors. Moreover, in small cells, the signal-to-noise ratio is large, while the small time dispersion allows the OFDM symbol cyclic prefix to prevent intersymbol interference. This retains the CFO to solely determine the BER and vice versa, enabling indirect estimation of CFO-induced phase distortion by simple BER testing. However, a particular problem is measuring very low BER values (generated by alike residual CFO), which could last a long time in order to acquire statistically enough errors. The test time can be drastically reduced if the noise margin is reduced in a controllable way, by adding the interfering signal to each subcarrier at the receiver. This approach is shown to enable efficient and accurate short-term BER (and so CFO phase error) testing.

In this paper we present an analytical model for planning and using network resources to improve network coverage, capacity and reliability, reduce network investment and maintenance costs, as well as reduce the electrical power consumption. The analysis considers the downlink of an arbitrary heterogeneous cellular network by using tools of stochastic geometry that adopts the distribution of base stations in the form of Poisson Point Process (PPP). To prove the analytical model, simulation based on ns-3 network simulator has been conducted, with accurately matching the theoretical values and boundaries.

Mobile operators are confronted with the fact that a large portion of the calls and data transfer take place indoors. The aim of this paper is to present an analytical model for the planning and use of network resources in the heterogeneous networks (multitier, multistandard) whose topology will enable network enhancements of indoor and outdoor coverage, capacities and reliability of communication, reduction of investment costs and maintenance of the network, as well as reduction of electricity consumption. This model should set the theoretical framework in which it is possible to upgrade efficiently the existing network with the least costs of network deployment, while at the same time providing the capacity to meet user requirements in the necessary places and at the required time. Accordingly, a set of values of network resource parameters is presented as one of the main results achieved by this model. Hence, this set grasps parameters' values which enable increased energy and spectral efficiency, as well as required capacities, the satisfactory level of quality of service, and rational energy consumption within the real network in the time domain. In addition, the results include the establishment of a connection with the necessary limit values of the radio signal parameters at the cell boundaries, considering all cell tiers.

The heterogeneous network concept in many respects meets customer requirements and maintains high energy efficiency. In this paper, we mainly investigate the impact of deployment efficiency of heterogeneous small cells BSs compared to the advantages of increasing the performance of wireless networks as a whole. We used well-known analytical models for calculating the values that can be obtained for certain network scenarios and compared them with the results of the simulation of the ns-3 simulator. This analysis shows that the introduction of small cells in traditional networks with an even distribution of base stations has a major impact on energy efficiency, and spectrum efficiency must be addressed by other mechanisms and radio resource management schemes. However, a major impact is shown in terms of significant cost reductions and CAPEX and OPEX.

As a profound and evident future trend in the field of mobile communication technologies development, heterogeneous networks became one of the crucial points of interests in wireless networks industry and academic research societies. Considering heterogeneous networks as an inseparable concept from LTE networks nowadays, which remain at position of advanced cellular system, the researchers aim to observe and solve the possible problems of inter-cell interference from the aspect of radio resource management. Hence, the lattermost trends consider heterogeneous networks through the process of connecting energy-efficient small cells to macrocells, due to undeniable importance of energy-efficient solution deployment, which was briefly presented in this paper. Also, the combination of radio resource management and heterogeneous networks turned out to be a practical compound of modern telecommunication techniques and technologies which provides a huge spectrum of possibilities for improving telecommunication services with minimized costs and increased efficiency of the whole system. The concept of radio resource management used in this paper was practically tested by small cells number variation within LTE HetNet set up in NS3 simulation environment.

The rapid growth of connected devices worldwide has dramatically increased demand for available spectrum. The changeover to spectrum efficient digital terrestrial TV transmission freed up large blocks of spectrum. This paper aims to offer the results of the analysis of 3G mobile network usage in terms of traffic based on the case of dominant mobile operator in Bosnia and Herzegovina (B&H). By this it is identified whether the demand for more radio spectrum is legitimate. In order to satisfy the requirement for extension of radio spectrum aimed for broadband services the broadcast spectrum (470 - 700 MHz) has been investigated. The rest of the UHF broadcast band (700 - 860 MHz) was not considered since it is specified as the Digital Dividend and hence was not a subject of dynamic access to the spectrum investigation. All results have been compared to the relevant researches conducted in some European, US, Asian and African countries. Ultimately the analysis results would help the modernization and enhancement of spectrum management proposing the concept of spectrum sharing and dynamic spectrum access to the national regulatory authority in B&H.

The basic functionalities of mobile network (voice service and mobility) do not satisfy all user requirements in the network. Thus the evolution of GSM was inevitable, as well as the emergence of user-oriented services. In this paper, implementation of a web service using USRP hardware device combined with OpenBTS software is described and analyzed.