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Ítem A flexible mid-term frequency domain scheduler for resource allocation in Hetnets based on the SINR requested by users(Institute of Electrical and Electronics Engineers Inc., 2014-11-05) Navarro Cadavid, AndrésThis article solves the resource allocation problem for the downlink of a multi-cell, multiservice Wireless Mobile Communications System (WMCS) with heterogeneous architecture deployed into an urban environment using Orthogonal Frequency Division Multiple Access (OFDMA) in its physical level. The optimization model aims to equitably satisfy services to users by making an efficient use of the available resources using the Signal to Interference-plus-Noise Ratio (SINR). It is a Mixed Integer Nonlinear Programming (MINLP) model whose solution is complex to obtain directly. The proposed solution algorithm decouples the solution space of the problem and uses an iterative and distributed approach to implement a frequency-domain scheduler in the medium term that uses a global vision of the system to allocate resources trying to obtain the SINR required for all users (the proposed goal). Since it is not always possible to achieve the proposed goal, we take advantage of the elasticity of some of the services offered and incorporating the slack variable ΔPref to solve it. The approach allows selecting the frequency allocation strategy, the exploration focus of the search space and the system administrator's vision.Ítem A flexible mid-term frequency domain scheduler for resource allocation in HetNets based on the SINR requested by users(Elsevier, 2015-03-01) Pachón de la Cruz, AlvaroThis article treats the resource allocation problem for the downlink of a multi-cell, multiservice Wireless Mobile Communications System (WMCS) with heterogeneous architecture deployed into an urban environment using Long Term Evolution (LTE) and Orthogonal Frequency Division Multiple Access (OFDMA) in its physical level. The optimization model aims to satisfy services to users by making an efficient use of the available resources, and a fair frequency block allocation, using the Signal to Interference-plus-Noise Ratio (SINR). It is a Mixed Integer Nonlinear Programming (MINLP) model whose solution is complex to obtain directly. The proposed solution algorithm decouples the solution space of the problem and uses an iterative and semi-distributed approach to implement a frequency-domain scheduler in the medium term that uses a global vision of the system to allocate resources trying to obtain the SINR required for all users (the proposed goal). Since it is not always possible to achieve it, we take advantage of the elasticity of some of the services offered and incorporate a slack variable to solve it. The approach allows selecting the frequency allocation strategy, the exploration focus of the search space and the system administrator's vision. The results obtained show that the implementation that uses a coordinated frequency allocation obtains better results in the amount of users with full satisfaction and in the use of power when compared to implementations using other frequency allocation strategies. In scenarios with heterogeneous architecture, the combined effect of picocells and coordinated frequency allocation improves the value for the defined performance metrics.Ítem Resource Allocation in OFDMA as an Optimization Problem(IGI Global, 2014-08-01) García Palomares, UbaldoWireless mobile communication systems (WMCS) face the challenge of satisfying the requirements of an increasing number of users demanding diverse services. WMCS service providers have multiple challenges: increasing number of users, full satisfaction of service requirements, and introduction of new technologies. Adequate resource management becomes a key factor for guaranteeing a successful relationship between service provider and users, for meeting system performance goals, and to achieve financial sustainability.