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In 5G, the small cell technology is proposed to cooperate with the cellular networks, and forms a Heterogeneous Network (HetNets) for achieving cooperative communications. The small cell-based cooperative communication brings several advantages: increasing system capacity in the indoor/outdoor hotspots, increasing wireless coverage, improving signal quality, reducing the eNB deployment cost, etc....
The paper proposes a customized frequency domain energy detection spectrum sensing scheme. It is needed to fulfill requirements provided by the IEEE 802.22 standard, aimed at extending Internet services to Television White Space frequencies. It provides a detection scheme allowing to achieve strict sensitivity required by the protocol either in sensing time or in detection capabilities. In particular,...
Same frequency networking (SFN) technology is widely used in modern wireless network to achieve high area spectrum efficiency. However, it brings the inter-cell interference to the users at the cell edge. Frequency allocation and power control is extensively used to diminish the effect of the interference. Most of the researches are focus on the downlink data transmission due to the fact that the...
In this paper, we propose an user-oriented graph based frequency allocation algorithm for downlink transmission in the heterogeneous network. As different users may use different communication service, they would have different data rate requirement. It is critical to fulfill all users' traffic demand before enlarging the system throughput. So, the optimization objective is simultaneously improving...
Due to higher cost and spectrum scarcity, it is expected that an efficient use of spectrum in fifth generation (5G) networks will rather rely on sharing than exclusive licenses, especially when higher frequency allocations are considered. In this paper, the performance of a dense indoor multi-operator small cell network at 10 GHz is analyzed. The main goal is to show the benefits obtained at higher...
Priority queue-based techniques improve spectrum efficiency by allocating the underutilized spectral bands (holes) of primary users to secondary users in Cognitive Radio Networks (CRN). This article proposes a Distributed Precedence Queuing scheme for Efficient Spectrum Management (DPQESM) in CRNs. The proposed method classifies the available channels into periodic and aperiodic based on the state...
Managing resources in wireless communication is a crucial task to ensure demand is satisfied at a minimal operational cost. This includes managing constraints such as co-frequency, adjacent frequency and co-site so that interference is avoided. Any occurrence of interference will affect the quality of communication conducted between parties involved. Therefore, a good and efficient method is required...
LTE networks are deployed to increase capacity and coverage especially for the indoor and cell-edge mobile users. However, such deployment comes with major challenges, radio resource management and inter-cell interferences. Fractional Frequency Reuse mechanism (FFR) is one of the most effective interference avoidance techniques. In this paper, we evaluate an existing adaptation process that adjusts...
Spectrum policy in the US (and throughout most of the world) consists generally of a set of nationally determined policies that apply uniformly to all localities. However, it is also true that there is considerable variation in the features (e.g., traffic demand or population density), requirements and constraints of spectrum use on a local basis. Global spectrum policies designed to resolve a situation...
To cope with the data surge problem and to enhance the coverage of existing cellular systems, heterogeneous networks (HetNets) are deployed in hierarchical manner, comprising of macrocells and overlaid femtocells. A novel interference mitigation technique of Reverse Frequency Allocation (RFA) scheme is introduced, which provides intercell orthogonality by dividing the cell into spatial regions and...
Channel allocation possibilities of femtocells are analyzed in this work. Femtocells have gained importance in the recent times because of their scope to offer better frequency reuse in cellular systems. They are poised to play their prominent role in future 5G systems also. While allocating the operating frequencies to femtocells, care needs to be taken to avoid interference with neighboring femtocells...
Due to the irregular topology of ultra dense cellular network (UDN), base station (BS)-centric methods are usually with low spectrum efficiency and not flexible for quality-of-service (QoS) guaranteeing. This paper investigates the QoS-aware interference coordination in UDN from a user-centric way (UCQA-IC). Targeting at enhancing the spectrum efficiency and user experience with controlled inter-cell-interference...
Resource allocation and user association are two key issues in the heterogeneous wireless cellular networks. The joint optimization on these two problems is considered as NP-hard and hence it is difficult to achieve the exact solution effectively. In this paper a novel shareable resource allocation and user association scheme is proposed with frequency reusing taken into consideration. The optimization...
UWB based on chirp waveforms has the advantages of low cost, low power consumption and high processing gain. A multiple access UWB system based on multi-chirp waveforms is proposed[ Sponsored by Tianjin science and technology planning project(No:13ZCZDSY20100)], which enables the system to gain merits of both IR-UWB and OFDM-UWB. System performance for multi-user UWB using multi-chirp waveforms is...
5G research shows more potential attention to mobile communications in information intensive industrial sectors such as power utility. In smart grid context, employing licensed assisted access (LAA) allows smart grid operators to transfer utility data between different sites using the unlicensed and licensed bands. This can play a crucial role in improving efficiency, sustainability, stability, and...
In LTE and LTE-Advanced small cells (i.e., femtocells) have shown great influence in ensuring higher quality of service (QoS). For 5G they will continue to play a vital role as well. In this paper we present an adaptive resource allocation (i.e., bandwidth and transmit power of femtocells) scheme which tries to mitigate the cross tier interference between femtocell and macrocell, ensuring overall...
The huge increase of high bandwidth demanding applications like interactive gaming, video streaming etc. over wireless channel and exponential growth of average mobile user population raise need of higher spectral density and cell capacity. The 4th Generation (4G) wireless network standardized as Long Term Evolution (LTE) utilizes advantages Orthogonal Frequency Division Multiple Access (OFDMA), where...
Currently, a number of different radio systems which are set up and work during a mission is growing rapidly. A traditional way to ensure coexistence of the radio systems and minimize interferences is a frequency allocation plan (pre-assigned frequencies) which is believed to be inefficient, whereas Dynamic Spectrum Access (DSA) is thought to introduce a more efficient spectrum usage. By using policy...
In this paper, we revisit the frequency allocation scheme (FAS) for the homogeneous cellular networks by taking the non-uniform distribution of users into account. Owing to the non-uniformly distributed user density from sector to sector, the traffic loads become highly unbalanced across whole network. Thus, to satisfy users' requests, the dynamic user-oriented FAS (Duo-FAS) is proposed to allocate...
In this paper we present the effects of Wi-Fi interference on a Wireless Sensor Network (WSN) in an aircraft. We use Time-Slotted Channel Hopping (IEEE 802.15.4e) as Link layer in the WSN network. We conduct measurements in an environment realistically representing an aircraft cabin. We provide the resulting application failure and packet drop rates with and without interference, for an exemplary...
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