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We present results from a detailed comparative study of the performance of three different frequency assignment schemes for interference management in heterogeneous LTE networks. Realistic indoor propagation models are used in order to obtain accurate results. We show that simple graph based frequency assignment schemes yield an excellent compromise between computational complexity and high performance...
Due to the exponential increment of spectrum requirement in multimedia application, leads to spectrum scarcity. Traditionally licensed spectrum is used only by licensees over relatively long time period with the help of FSA (fixed spectrum allocation) which guarantees the licensed authorized party without interference. According to FCC records, utilization efficiency varies between 15% to 85%, for...
Fractional Frequency Reuse (FFR) schemes are frequency allocation techniques used in cellular systems for interference mitigation and enhancing resource utilization. In this paper, analysis is presented comparing FFR and other FR algorithms under realistic network situations. Most implementations in literature considered uniform mobile placements and perfect grid models where well-defined hexagonal...
The aim of this paper is to summarize spectrum allocation aspects related to the control and non-payload communications link(s) for unmanned aircraft systems. We take into account the corresponding studies of ITU-R, the position of ICAO and related resolutions of world radiocommunication conferences. In addition, the current situation of the spectrum allocation for unmanned aircraft systems control...
Due to Orthogonal Frequency Division Multiple Access (OFDMA) mechanism adopted in LTE cellular networks, intra-cell interference is nearly absent. Yet, as these networks are designed for a frequency reuse factor of 1 to maximize the utilization of the licensed bandwidth, inter-cell interference coordination remains an important challenge. In both homogeneous and heterogeneous cellular networks, there...
The paper provides an overview of various techniques used to avoid intercell interference (ICI) in MIMO OFDMA systems. ICI occurs in a cellular communication system when adjacent cells use the same radio resources, i.e. frequency reuse of unity. This interference experienced is maximum by the edge users. The edge users suffer from severe ICI leading to throughput degradation. Hence edge users contribute...
The aim of the paper is to discuss and analyze the recent solutions based on coordinated Inter Cell Interference (ICI) techniques premeditated by researchers. The most thriving need of improved spectral density and user data throughput demands dense deployment of base stations and simultaneous resource allocation in same geographical area. This approach eases the problem of spectrum scarcity but increases...
Resource optimization becomes mandatory in radio spectrum because of limited resources. The effective utilization of resources is the need of wireless era. Cognitive radio is a technology which enables opportunistic access to radio spectrum and has ability to analyze and learn about the environment conditions. Most of the radio spectrum is underutilized. Cognitive radio has the ability to sense the...
The ever growing mobile data traffic, due to increasing data demand of increasing number of users, has motivated researchers to analyze performance of next generation heterogeneous wireless network (xGHWnet). The xGHWnet consists of micro base station (mBS) of Long Term Evolution (LTE) or Long Term Evolution-Advanced (LTE-advanced) mobile cellular network and pico hotpot(s) to cover dead zone or number...
The recent and rapid evolution of wireless technologies has led to a high demand in terms of resources. To solve the problem the idea of cognitive radio has been introduced to facilitate a good spectrum management and efficient use of the spectrum. In this article we present the spectrum sensing techniques which is a very important step in cognitive radio. The energy detection method used in this...
Aiming the problem that it is difficult for the stationary spectrum allocation method of existing HF access network to meet the requirement of intelligent frequency hopping technology, the communication requirement of intelligent frequency hopping HF access network is analyzed in this paper, to come up with the dynamic frequency spectrum allocation strategy and algorithm of maximum handling capacity...
Wireless networks employing small cells like femtocells are considered to be the choice of network deployment for 4G or advanced networks. This hierarchical deployment of cells introduces the necessity of effective frequency planning for mitigation of interference between different layers of network. As the scarce spectrum resources are likely to be reused to increase spectral efficiency, interference...
More cooperation or coordination is necessary for future UDN (Ultra-Dense Network) scenario of 5G network, of which ICIC (Inter-Cell Interference Coordination) is a promising and typical scheme. Cooperating cellular network may be thought as a special kind of distributed computing system, whose basic theory and toolsets could be adopted. CAP theory for distributed computing state that any networked...
Increasing demand for quality, high speed mobile services, and the expected socioeconomic benefits associated to them, have turned the attention to the need for radio spectrum with specific characteristics. The underlying reason is that such services require spectrum which is a scarce and highly valuable input. Consequently, many countries have reassigned portions of spectrum in order to maximize...
In this paper we compare three novel schemes for dynamic frequency allocation and transmission power assignment for cognitive radio networks. These spectrum allocation schemes are based on reinforcement learning and power optimization procedures. We propose the so-called RL+Power and RL+Power Coupled schemes and compare them with an existing constant power scheme. Simulation results show that the...
Next generation tactical networks has to provide high data rate and low delay, along with multiple applications with strict QoS requirements. In this work we address the problems of clustering and frequency allocation in TDMA-based frequency-hopping tactical networks. We propose Mixed Integer Linear Programming based optimal clustering solution along with a distributively implementable load-balanced...
Mobile Ad-Hoc Network (MANET) is the foundational technology for the Army's network modernization. Thus, spectrum management of MANETs is critical to efficient and effective MANET acquisition and deployment. The technical basis for the tactical spectrum management process is interference analysis. The results of interference analysis are highly dependent on the choice of interference protection criteria...
Recently, with the fast development of wireless communications, the radio spectrum has become a precious natural resource. Cognitive radio (CR) has been proposed as an important means to promote efficient use of the spectrum by exploiting the existence of spectrum holes. In this paper, we utilize wavelet packets to achieve spectrum management and signature waveform design for CR users. With legacy...
Fractional Frequency Reuse (FFR) and Coordinated Multi Point (CoMP) processing are two of the conventional methods to mitigate the Inter-Cell Interference (ICI) and to improve the average Signal-to-Interference-plus-Noise Ratio (SINR). However, FFR is associated with low system spectral efficiency and CoMP does not take any action to mitigate the inter-cluster interference. In the context of Cloud...
Due to its high data rate support and other salient features, LTE-Advanced (LTE-A) has been chosen as a promising technology for Internet of Things with billions of devices being connected and managed. Sufficient frequency resource and appropriate interference coordination techniques are eagerly needed to accommodate the network requirements. In this paper, to deal with the inter-cell interference...
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