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In this paper, a distributed and autonomous technique for resource and power allocation in orthogonal frequency division multiple access (OFDMA) femto-cellular networks is presented. Here, resource blocks (RBs) and their corresponding transmit powers are assigned to the user(s) in each cell individually without explicit coordination between femto-base stations (FBSs). The "allocatability" of each resource is determined utilising only locally available information of the following quantities:• the required rate of the user;• the quality (i.e., strength) of the desired signal;• the level of interference incident on each RB; and• the frequency-selective fading on each RB.Using a fuzzy logic system, the time-averaged values of each of these inputs are combined to determine which RBs are most suitable to be allocated in a particular cell, i.e., which resources can be assigned such that the user requested rate(s) in that cell are satisfied. Furthermore, link adaptation (LA) is included, enabling users to adjust to varying channel conditions. A comprehensive study in a femto-cell environment is performed, yielding system performance improvements in terms of throughput, energy efficiency and coverage over state-of-the-art inter-cell interference coordination (ICIC) techniques. Index Termsautonomous resource allocation, distributed ICIC, fuzzy logic, OFDMA, femto-cellular networks. I. INTRODUCTIONFuture wireless networks are moving towards heterogeneous architectures, where in each cell a user may have over four different types of access points (APs) (e.g., macro-, pico-, femtocells, relays and/or remote radio heads) [1]. Intuitively, this has many positive effects for a September 14, 2018 DRAFT 2 mobile station (MS), which can now choose from several base stations (BSs) to find the most suitable. However, pico-and femto-cellular overlays also imbue many difficulties, e.g., cellorganisation/optimisation, resource assignment to users, and especially interference coordination between APs within the same and neighbouring cells. Standard inter-cell interference coordination (ICIC) techniques based on network architectures [2, 3] only go so far in dealing with these challenges, and hence a new approach is necessary. A. Challenges in Heterogeneous Networks (HetNets)Through the various types, locations and dense deployment of APs, and the different transmissions powers/ranges associated with them, numerous technical challenges are posed by femto/picocell overlays [1,4,5]. These mainly fall into the following areas:• Network self-organisation -Self-configuration and -optimisation are required of all cells.In cellular networks, such organisation can be performed via optimisation techniques [6], however these tasks become increasingly difficult given the additional APs and network parameters to be considered, motivating a distributed configuration approach [7].• Backhauling -Connecting the different BSs to the core-network necessitates extra infrastructure [1]. In the femto-cell case, the long delay of connection via wired backhaul...

One of the key challenges for future orthogonal frequency division multiple access-based networks is inter-cell interference coordination. With full frequency reuse and small inter-site distances, coping with co-channel interference (CCI) in such networks has become increasingly important. In this article, an uplink interference protection (ULIP) technique to combat CCI is introduced and investigated. The level of uplink interference originating from neighbouring cells (affecting co-channel mobile stations (MSs) in the cell of interest) can be effectively controlled by reducing the transmit power of the interfering MSs. This is done based on the target signal-to-noise-plus-interference ratio (SINR) and tolerable interference of the vulnerable link. Bands are prioritised in order to differentiate those (vulnerable/victim) MSs that are to be protected from interference and those (aggressor/interfering MSs) that are required to sacrifice transmission power to facilitate the protection. Furthermore, MSs are scheduled such that those users with poorer transmission conditions receive the highest interference protection, thus balancing the areal SINR distribution and creating a fairer allocation of the available resources. In addition to interference protection, the individual power reductions also serve to decrease the total system uplink power, resulting in a greener system. It is shown through analytic derivation that the introduction of ULIP guarantees an increase in energy efficiency for all MSs, with the added benefit that gains in overall system throughput are also achievable. Extensive system level simulations validate these findings.

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In this paper, Pareto Femto-Cell Scheduling (PFCS), a novel scheduling mechanism for randomly deployed femtocells, is presented. Here, the signal-to-interference-plus-noise ratio (SINR) targets of femto-users are adapted such that the sufficient conditions for Pareto optimal power control (POPC) are fulfilled. Furthermore, interference from full bandwidth users is managed such that as many mobile stations (MSs) as possible can transmit. Due to the random nature of femto-base station (FBS) deployment, interference graphs are used to group femtocells (and hence, users) such that target spectral efficiencies can be achieved at Pareto optimum power. Simulation results show that PFCS achieves significant system capacity gains over other SINR-target-based power allocation techniques, while maximising coverage in dense mobile environments. Furthermore, substantial power savings can be achieved.

Introduction: The objective of this paper is to demonstrate techniques on how to improve hip flexibility and mobility, especially for track and field athletes. It also seeks to explain the underlying importance of hip flexibility and mobility. When athlete's hips are stiff and inflexible, muscle imbalance may occur and increase the risk of injury. Muscle imbalance in the hip often causes knee and hip pain, due to the hip flexors and quadriceps overworking in order to compensate for weaker muscles. The hip mobility and flexibility exercises illustrated here are designed to significantly improve the range of motion (ROM) of the hips. Enhanced ROM can improve motor performance, skill execution, and even prevent injury. Excellent hip extension improves the ability to assist the hip in developing power. Methods: 9 Hip Mobility and 6 Hip Flexibility exercises are described in this paper. The exercises are to be performed 3× per week with at least 24 hours break in-between to achieve optimum results. Conclusion: This paper sought to outline the importance of hip mobility and flexibility, in particular for non-contact-sport athletes (such as those in track and field), and their effects on athletic performance and injury prevention. After proximately 6 weeks, the ROM of the hip will be expected to improve significantly.

In this paper the capacity of decentralized wireless networks is addressed. An exclusion region is introduced that protects active receivers from destructive interference of nearby transmitters. An exclusion range imposes an upper bound on the interference that a transmitter may cause to receivers of competing links. While an exclusion region avoids excessive interference and thus improves capacity per link, the spatial reuse in terms of concurrently served links is compromised. The resulting trade-off is elaborated by computer simulations, so to optimize the exclusion range as a function of the user density and maximum transmit power. We demonstrate that by an appropriately specified exclusion range, the network capacity is substantially enhanced. In this context, it has been found that the exclusion range that maximizes the system capacity does not vary greatly when changing the a priori user density. In addition, the trade-off between maximizing the system capacity and maintaining fairness is investigated.Index Terms-Network capacity, interference temperature constraint, decentralized interference management, receiver feedback, multiple access.