"RIV/68407700:21230/14:00224892" . "Be\u010Dv\u00E1\u0159, Zden\u011Bk" . . "2"^^ . . "Silicon Valley" . "In this paper, we introduce new concept for femtocells with the purpose to minimize cross-tier interference to the macrocell users (MUEs). The cross-tier interference is mitigated by the power control algorithm minimizing the power level and, thus, ensuring that all currently active femto users (FUEs) can attach to the femto access points (FAPs). To guarantee quality of service to the FUEs even at heavy load, despite low transmitting power, the FAPs can opportunistically utilize also SU bands. To that end, we denote our scheme as a hybrid cognitive approach, which is distinguished by the fact that the FAPs can access bandwidth as a primary users (PU) and secondary users (SU) at the same time. In order to generate less overhead introduced by sensing for the purpose of determining available spectrum, we also propose an algorithm that adaptively changes a sensing period. The results show that our proposal is able to significantly reduce cross-tier interference nearly to the same level as achieved by algorithms focusing on maximization of the MUEs' performance. At the same time, our proposal ensures that the performance of the FUEs is kept at satisfactory level similarly as in the case of the algorithms focusing solely on the performance of the FUEs."@en . "Hybrid Cognitive Approach for Femtocell Interference Mitigation" . . "interference mitigation; femtocell; cognitive capabilities; sensing; power control"@en . "2"^^ . "The Thirteenth International Conference on Networks Proceeding" . "[6AF89964C9F5]" . "Hybrid Cognitive Approach for Femtocell Interference Mitigation"@en . "20035" . . "International Academy, Research and Industry Association (IARIA)" . . . "RIV/68407700:21230/14:00224892!RIV15-GA0-21230___" . "Hybrid Cognitive Approach for Femtocell Interference Mitigation" . . . "Nice" . . "In this paper, we introduce new concept for femtocells with the purpose to minimize cross-tier interference to the macrocell users (MUEs). The cross-tier interference is mitigated by the power control algorithm minimizing the power level and, thus, ensuring that all currently active femto users (FUEs) can attach to the femto access points (FAPs). To guarantee quality of service to the FUEs even at heavy load, despite low transmitting power, the FAPs can opportunistically utilize also SU bands. To that end, we denote our scheme as a hybrid cognitive approach, which is distinguished by the fact that the FAPs can access bandwidth as a primary users (PU) and secondary users (SU) at the same time. In order to generate less overhead introduced by sensing for the purpose of determining available spectrum, we also propose an algorithm that adaptively changes a sensing period. The results show that our proposal is able to significantly reduce cross-tier interference nearly to the same level as achieved by algorithms focusing on maximization of the MUEs' performance. At the same time, our proposal ensures that the performance of the FUEs is kept at satisfactory level similarly as in the case of the algorithms focusing solely on the performance of the FUEs." . . . . "Hybrid Cognitive Approach for Femtocell Interference Mitigation"@en . . . . "21230" . . "2014-02-23+01:00"^^ . "P(GP13-24931P)" . "8"^^ . . . "978-1-61208-318-6" . . "Mach, Pavel" .