http://hdl.handle.net/2117/7268 Sun, 19 May 2013 14:51:39 GMT 2013-05-19T14:51:39Z webmaster.bupc@upc.edu Universitat Politècnica de Catalunya. Servei de Biblioteques i Documentació no http://hdl.handle.net/2117/19328 Title: Simulation of LTE IR H-ARQ at system level using MIESM error prediction Authors: Olmos Bonafé, Juan José; Serra, Albert; García Lozano, Mario; Ruiz Boqué, Sílvia; Pérez Díaz de Cerio, David Fri, 17 May 2013 11:30:15 GMT http://hdl.handle.net/2117/19328 2013-05-17T11:30:15Z Olmos Bonafé, Juan José; Serra, Albert; García Lozano, Mario; Ruiz Boqué, Sílvia; Pérez Díaz de Cerio, David no http://hdl.handle.net/2117/18860 Title: Energy-efficiency evaluation of a medium access control protocol for cooperative ARQ Authors: Alonso Zárate, Jesús; Stavrou, Eirini; Stamou, Adamantia; Angelidis, Pantelis; Alonso Zárate, Luis Gonzaga; Verikoukis, Christos Abstract: We present in this paper the evaluation of the energy consumption of PRCSMA, an 802.11-based medium access control protocol designed to coordinate the retransmissions from the relays in a wireless network implementing a Cooperative Automatic Retransmission Request (C-ARQ) scheme. A comparison in terms of energy efficiency with non-cooperative ARQ schemes (retransmissions performed only from the source) and with ideal C-ARQ (with perfect scheduling among the relays) is included in this paper. The main results show the conditions under which a C-ARQ scheme with PRCSMA outperforms, in terms of energy efficiency, non-cooperative ARQ schemes and also show that the overhead of the MAC layer cannot be neglected in order to accurately evaluate the performance of a C-ARQ scheme. Description: Best Paper Award in Communications QoS, Reliability and Modelling. IEEE ICC 2011 Thu, 18 Apr 2013 09:57:56 GMT http://hdl.handle.net/2117/18860 2013-04-18T09:57:56Z Alonso Zárate, Jesús; Stavrou, Eirini; Stamou, Adamantia; Angelidis, Pantelis; Alonso Zárate, Luis Gonzaga; Verikoukis, Christos no We present in this paper the evaluation of the energy consumption of PRCSMA, an 802.11-based medium access control protocol designed to coordinate the retransmissions from the relays in a wireless network implementing a Cooperative Automatic Retransmission Request (C-ARQ) scheme. A comparison in terms of energy efficiency with non-cooperative ARQ schemes (retransmissions performed only from the source) and with ideal C-ARQ (with perfect scheduling among the relays) is included in this paper. The main results show the conditions under which a C-ARQ scheme with PRCSMA outperforms, in terms of energy efficiency, non-cooperative ARQ schemes and also show that the overhead of the MAC layer cannot be neglected in order to accurately evaluate the performance of a C-ARQ scheme. http://hdl.handle.net/2117/18762 Title: Multi-radio cooperative retransmission scheme for reliable machine-to-machine multicast services Authors: Laya Romero, Andrés Ernesto; Wang, Kun; Alonso Zárate, Luis Gonzaga; Alonso Zárate, Jesús Abstract: Mobile Machine-to-Machine (M2M) market is expected to grow dramatically in the upcoming years; predictions agree that the majority of wireless traffic will correspond to this type of communication. M2M devices deployed in proximity to each other might be handled as groups or clusters when sharing the same communication attributes and serving to achieve joint target. Moreover, devices that feature multiple radio interfaces are commonly used nowadays; they can be connected to a cellular access network, e.g., LTE, and simultaneously to a short-range network, also known as capillary network, among surrounding devices, e.g., Wi-Fi and ZigBee. For services such as over-the-air (OTA) firmware update, the same information shall be sent to all the group members over the cellular access network. A Multi-Radio Cooperative Retransmission Scheme for Reliable Multicast Services is presented as a solution to reliably manage reception errors occurred over the cellular network; by carrying out retransmissions over a short-range network it is possible to reduce both the traffic load over the cellular link and the energy consumption in error recovery. Ns-3 simulations were performed with LTE network models to analyze the scheme in terms of energy consumption and prove its usefulness in autonomous, battery driven, devices. Wed, 10 Apr 2013 16:17:35 GMT http://hdl.handle.net/2117/18762 2013-04-10T16:17:35Z Laya Romero, Andrés Ernesto; Wang, Kun; Alonso Zárate, Luis Gonzaga; Alonso Zárate, Jesús no Machine-to-Machine, Multi-Radio Cooperation, Cooperative ARQ, Energy Efficiency Mobile Machine-to-Machine (M2M) market is expected to grow dramatically in the upcoming years; predictions agree that the majority of wireless traffic will correspond to this type of communication. M2M devices deployed in proximity to each other might be handled as groups or clusters when sharing the same communication attributes and serving to achieve joint target. Moreover, devices that feature multiple radio interfaces are commonly used nowadays; they can be connected to a cellular access network, e.g., LTE, and simultaneously to a short-range network, also known as capillary network, among surrounding devices, e.g., Wi-Fi and ZigBee. For services such as over-the-air (OTA) firmware update, the same information shall be sent to all the group members over the cellular access network. A Multi-Radio Cooperative Retransmission Scheme for Reliable Multicast Services is presented as a solution to reliably manage reception errors occurred over the cellular network; by carrying out retransmissions over a short-range network it is possible to reduce both the traffic load over the cellular link and the energy consumption in error recovery. Ns-3 simulations were performed with LTE network models to analyze the scheme in terms of energy consumption and prove its usefulness in autonomous, battery driven, devices. http://hdl.handle.net/2117/18654 Title: Improved scheduling decisions for LTE-A uplink based on MPR information Authors: Lema, Maria A.; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José Abstract: Advanced (LTE-A) allows for non-contiguous resource allocation in the uplink. The aim is to increase the spectral efficiency by exploiting users’ frequency diversity gain. This feature implies that clustered-DFT-S-OFDM must be used in the uplink, no longer preserving the single carrier property of previous releases. Multi-cluster transmission brings an increase in the signal’s Peak-to-Average Power Ratio (PAPR) and so power de-rating must be introduced to control out-of-band emissions. Maximum power Reduction (MPR) can counteract the frequency gain and bring losses to the users’ performance. This paper proposes a novel scheduler that considers the MPR information. The packet scheduler’s main task is to evaluate the gain or loss in throughput of the multi-cluster transmission over a conventional contiguous one. Based on the Sounding Reference Signals (SRSs) channel estimation, the eNB can predict the multi- cluster transmission’s performance. Results show that enabling the MPR information in the scheduler adapts the transmission mode to each particular case, enhancing the system throughput Fri, 05 Apr 2013 15:27:25 GMT http://hdl.handle.net/2117/18654 2013-04-05T15:27:25Z Lema, Maria A.; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José no Advanced (LTE-A) allows for non-contiguous resource allocation in the uplink. The aim is to increase the spectral efficiency by exploiting users’ frequency diversity gain. This feature implies that clustered-DFT-S-OFDM must be used in the uplink, no longer preserving the single carrier property of previous releases. Multi-cluster transmission brings an increase in the signal’s Peak-to-Average Power Ratio (PAPR) and so power de-rating must be introduced to control out-of-band emissions. Maximum power Reduction (MPR) can counteract the frequency gain and bring losses to the users’ performance. This paper proposes a novel scheduler that considers the MPR information. The packet scheduler’s main task is to evaluate the gain or loss in throughput of the multi-cluster transmission over a conventional contiguous one. Based on the Sounding Reference Signals (SRSs) channel estimation, the eNB can predict the multi- cluster transmission’s performance. Results show that enabling the MPR information in the scheduler adapts the transmission mode to each particular case, enhancing the system throughput http://hdl.handle.net/2117/18254 Title: Modelling channel estimation error in LTE link level simulations Authors: Serra, Albert; Olmos Bonafé, Juan José; Lema Rosas, María Ángel Abstract: Channel estimation is a key aspect for the performance of the physical layer in all MIMO-OFDM systems. In order to obtain realistic performance assessments from the LTE link level simulator, channel estimation errors must be taken into account. Implementing a detailed channel estimation algorithm may lead to long simulation time, in particular for wideband MIMO transmission modes where many channels have to be estimated, and for procedures like Wiener filtering which require matrix multiplications. In this paper we propose to simulate channel estimation errors by a Gaussian additive noise error model. The noise variance of the model is calibrated as a function of the received SNR for different channel models and Doppler spreads. The model is validated by comparing the BLER curves obtained with the model with the curves obtained when using real channel estimation. Wed, 13 Mar 2013 10:39:31 GMT http://hdl.handle.net/2117/18254 2013-03-13T10:39:31Z Serra, Albert; Olmos Bonafé, Juan José; Lema Rosas, María Ángel no Channel estimation is a key aspect for the performance of the physical layer in all MIMO-OFDM systems. In order to obtain realistic performance assessments from the LTE link level simulator, channel estimation errors must be taken into account. Implementing a detailed channel estimation algorithm may lead to long simulation time, in particular for wideband MIMO transmission modes where many channels have to be estimated, and for procedures like Wiener filtering which require matrix multiplications. In this paper we propose to simulate channel estimation errors by a Gaussian additive noise error model. The noise variance of the model is calibrated as a function of the received SNR for different channel models and Doppler spreads. The model is validated by comparing the BLER curves obtained with the model with the curves obtained when using real channel estimation. http://hdl.handle.net/2117/18109 Title: Optimization of realistic full frequency reuse OFDMA-based cellular networks Authors: González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José; Lee, Dong Seop Abstract: Nowadays mobile operators are planning and de- signing their mid/long term strategies based on new OFDMA- based cellular technologies such as LTE and WiMAX. Co-siting and re-utilization of existing facilities are within their roadmap in order to keep CAPEX as low as possible. Therefore, the optimization of OFDMA networks subject to fixed/previous (and usually suboptimal) coverage is mandatory. In addition, recently there is a great interest in reducing OPEX mainly by means of energy savings. This paper presents a novel multiobjective formulation aiming at improving the performance of OFDMA networks where full frequency reuse is employed. The proposed framework is flexible and results indicate that it is also effective as it improves both spectral efficiency and cell edge performance while it simultaneously reduces energy consumption. Wed, 06 Mar 2013 15:09:28 GMT http://hdl.handle.net/2117/18109 2013-03-06T15:09:28Z González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José; Lee, Dong Seop no Nowadays mobile operators are planning and de- signing their mid/long term strategies based on new OFDMA- based cellular technologies such as LTE and WiMAX. Co-siting and re-utilization of existing facilities are within their roadmap in order to keep CAPEX as low as possible. Therefore, the optimization of OFDMA networks subject to fixed/previous (and usually suboptimal) coverage is mandatory. In addition, recently there is a great interest in reducing OPEX mainly by means of energy savings. This paper presents a novel multiobjective formulation aiming at improving the performance of OFDMA networks where full frequency reuse is employed. The proposed framework is flexible and results indicate that it is also effective as it improves both spectral efficiency and cell edge performance while it simultaneously reduces energy consumption. http://hdl.handle.net/2117/17899 Title: Help4Mood: testing and achievements of the first wireless sensor network prototype Authors: Pérez Díaz de Cerio, David; Ruiz Boqué, Sílvia; Rosell Ferrer, Francisco Javier; Ramos Castro, Juan José; Colomé Castellví, Josep Maria Abstract: Help4Mood is a closed loop approach supporting the control, communication and treatment management of patients with Major Depression. The first out of the three main components of the Help4Mood solution is the Personal Monitoring System (PMS), a set of different wireless sensors whose data sink is centralized on a laptop. The objective of this PMS is to monitor the activity of the patients, so several sensors have been chosen to cover the needs of different individuals. These include a wrist watch, a key ring, a waist/belt sensor, an under mattress sensor and a cellular phone. This paper describes the first prototype and the results obtained from this Wireless Sensor Network Wed, 20 Feb 2013 16:51:31 GMT http://hdl.handle.net/2117/17899 2013-02-20T16:51:31Z Pérez Díaz de Cerio, David; Ruiz Boqué, Sílvia; Rosell Ferrer, Francisco Javier; Ramos Castro, Juan José; Colomé Castellví, Josep Maria no Help4Mood is a closed loop approach supporting the control, communication and treatment management of patients with Major Depression. The first out of the three main components of the Help4Mood solution is the Personal Monitoring System (PMS), a set of different wireless sensors whose data sink is centralized on a laptop. The objective of this PMS is to monitor the activity of the patients, so several sensors have been chosen to cover the needs of different individuals. These include a wrist watch, a key ring, a waist/belt sensor, an under mattress sensor and a cellular phone. This paper describes the first prototype and the results obtained from this Wireless Sensor Network http://hdl.handle.net/2117/17887 Title: Improving soft frequency reuse for realistic OFDMA-based cellular deployments Authors: González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Lee, DongSeop Abstract: Effective interference management is a technical challenge of utmost importance for emerging OFDMA-based technologies such as Long Term Evolution (LTE) and Worldwide Interoperability for Microwave Access (WiMAX). Static Intercell Interference Coordination techniques including Soft Frequency Reuse (SFR) have enjoyed acceptance among mobile operators as a solution to deal with this problem mainly due to their low complexity and easy implementability. However, recent results indicate that the performance of default SFR settings directly applied to realistic cellular deployments is quite suboptimal and hence optimization is mandatory. This paper addresses this issue by presenting a novel multiobjective framework able to achieve accurate fine tuning of SFR and hence, enhance system capacity and cell edge performance while reducing energy consumption. Tue, 19 Feb 2013 15:51:57 GMT http://hdl.handle.net/2117/17887 2013-02-19T15:51:57Z González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Lee, DongSeop no Effective interference management is a technical challenge of utmost importance for emerging OFDMA-based technologies such as Long Term Evolution (LTE) and Worldwide Interoperability for Microwave Access (WiMAX). Static Intercell Interference Coordination techniques including Soft Frequency Reuse (SFR) have enjoyed acceptance among mobile operators as a solution to deal with this problem mainly due to their low complexity and easy implementability. However, recent results indicate that the performance of default SFR settings directly applied to realistic cellular deployments is quite suboptimal and hence optimization is mandatory. This paper addresses this issue by presenting a novel multiobjective framework able to achieve accurate fine tuning of SFR and hence, enhance system capacity and cell edge performance while reducing energy consumption. http://hdl.handle.net/2117/17723 Title: A wireless sensor network design for the Help4Mood european project Authors: Pérez Díaz de Cerio, David; Ruiz Boqué, Sílvia; Rosell Ferrer, Francisco Javier; Ramos Castro, Juan José; Castro Robles, Joan Carles Abstract: Help4Mood is a closed loop approach supporting the control, communication and treatment management of patients with Major Depression. The first out of the three main components of the Help4Mood solution is the Personal Monitoring System (PMS), a set of different wireless sensors whose data sink is centralized on a laptop. The objective of this PMS is to monitor the activity of the patients, so several sensors have been chosen to cover the needs of different individuals. These include a wrist watch, a key ring, a waist/belt sensor, an under mattress sensor and a cellular phone. This paper describes the first prototype and the results obtained from this Wireless Sensor Network. Wed, 13 Feb 2013 14:33:25 GMT http://hdl.handle.net/2117/17723 2013-02-13T14:33:25Z Pérez Díaz de Cerio, David; Ruiz Boqué, Sílvia; Rosell Ferrer, Francisco Javier; Ramos Castro, Juan José; Castro Robles, Joan Carles no Help4Mood is a closed loop approach supporting the control, communication and treatment management of patients with Major Depression. The first out of the three main components of the Help4Mood solution is the Personal Monitoring System (PMS), a set of different wireless sensors whose data sink is centralized on a laptop. The objective of this PMS is to monitor the activity of the patients, so several sensors have been chosen to cover the needs of different individuals. These include a wrist watch, a key ring, a waist/belt sensor, an under mattress sensor and a cellular phone. This paper describes the first prototype and the results obtained from this Wireless Sensor Network. http://hdl.handle.net/2117/17512 Title: Help4Mood personal monitoring system: management of interoperatibilty in a wireless home for mental health treatment Authors: Castro, Juan Carlos; Estevez, Soraya; Aragonés, Carlos; Pérez Díaz de Cerio, David; Ruiz Boqué, Sílvia Abstract: Help4Mood is a project inside 7th European Framework Programme (FP7) for developing a computational distributed system to support remotely the treatment of patients with major depression at home. Core components are integrated with the ICE framework. One of the main goals of this system is to use the paradigm of a Virtual Agent to support the first symptoms of clinician alert of a patient, to interact with him an to prevent some causes of relapse after monitoring he/she with different sensors. The system processes inputs from different devices for monitoring patient activity at home and how he/she sleeps (also know as the Personal Monitoring System), transmitting this data to a Decision Support System, and defining how a Virtual Agent should interact with the patient before clinical support from hospital is needed if an alert is detected. This data is transmitted by a wireless network designed to improve data communication from sensors in a home environment (easy of installation and maintenance) and implemented using customized protocols and algorithms for reducing power consumption of these sensors. The technical framework is using open source implementations of ICE and HL7-standard-based healthcare integration engines to interact with the different subsystems. Particularly, the use of these standards will contribute to commercialization of the project results and the potential impact through the development, dissemination and use. Thu, 24 Jan 2013 16:26:25 GMT http://hdl.handle.net/2117/17512 2013-01-24T16:26:25Z Castro, Juan Carlos; Estevez, Soraya; Aragonés, Carlos; Pérez Díaz de Cerio, David; Ruiz Boqué, Sílvia no Help4Mood is a project inside 7th European Framework Programme (FP7) for developing a computational distributed system to support remotely the treatment of patients with major depression at home. Core components are integrated with the ICE framework. One of the main goals of this system is to use the paradigm of a Virtual Agent to support the first symptoms of clinician alert of a patient, to interact with him an to prevent some causes of relapse after monitoring he/she with different sensors. The system processes inputs from different devices for monitoring patient activity at home and how he/she sleeps (also know as the Personal Monitoring System), transmitting this data to a Decision Support System, and defining how a Virtual Agent should interact with the patient before clinical support from hospital is needed if an alert is detected. This data is transmitted by a wireless network designed to improve data communication from sensors in a home environment (easy of installation and maintenance) and implemented using customized protocols and algorithms for reducing power consumption of these sensors. The technical framework is using open source implementations of ICE and HL7-standard-based healthcare integration engines to interact with the different subsystems. Particularly, the use of these standards will contribute to commercialization of the project results and the potential impact through the development, dissemination and use. http://hdl.handle.net/2117/17505 Title: Improving channel state information feedback for static Intercell interference coordination in LTE Authors: González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José Abstract: Intercell Interference is the main issue limiting the capacity of modern OFDMA-based cellular networks. Recently, extensive research work has been focused on intercell interference coordination since it has been recognized as a key concept to achieve seamless levels of quality of service. Nevertheless, very often this problematic is addressed as a standalone issue. In this work, a novel channel state information feedback scheme is proposed aiming at improving the overall system performance when both channel state information and static interference coordination are jointly considered. By means of the proposed scheme, gains in terms of users throughput, cell edge performance and energy efficiency are achieved with respect to existing aperiodic LTE-based mechanisms without additional complexity. Wed, 23 Jan 2013 17:33:44 GMT http://hdl.handle.net/2117/17505 2013-01-23T17:33:44Z González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José no Intercell Interference is the main issue limiting the capacity of modern OFDMA-based cellular networks. Recently, extensive research work has been focused on intercell interference coordination since it has been recognized as a key concept to achieve seamless levels of quality of service. Nevertheless, very often this problematic is addressed as a standalone issue. In this work, a novel channel state information feedback scheme is proposed aiming at improving the overall system performance when both channel state information and static interference coordination are jointly considered. By means of the proposed scheme, gains in terms of users throughput, cell edge performance and energy efficiency are achieved with respect to existing aperiodic LTE-based mechanisms without additional complexity. http://hdl.handle.net/2117/17504 Title: "Green" distance-aware base station sleeping algorithm in LTE-advanced Authors: Bousia, Alexandra; Antonopoulos, Angelos; Alonso Zárate, Luis Gonzaga; Verikoukis, Christos Abstract: In this paper, we propose a switch on/off algorithm for Base Stations (BSs), which exploits the knowledge of the distance between the User Equipments (UEs) and their associated BS. Our novel approach hopes to provide an improvement to the problem of energy consumption. The major concern lies on reducing the energy consumption of the telecommunication networks by optimizing the power utilization without sacrificing the offered Quality of Service (QoS). Our proposed scheme achieves a significant power saving, based on switching off the Base Stations that are underutilized during low traffic periods (especially during night) in the LTE-Advanced. Wed, 23 Jan 2013 17:25:58 GMT http://hdl.handle.net/2117/17504 2013-01-23T17:25:58Z Bousia, Alexandra; Antonopoulos, Angelos; Alonso Zárate, Luis Gonzaga; Verikoukis, Christos no In this paper, we propose a switch on/off algorithm for Base Stations (BSs), which exploits the knowledge of the distance between the User Equipments (UEs) and their associated BS. Our novel approach hopes to provide an improvement to the problem of energy consumption. The major concern lies on reducing the energy consumption of the telecommunication networks by optimizing the power utilization without sacrificing the offered Quality of Service (QoS). Our proposed scheme achieves a significant power saving, based on switching off the Base Stations that are underutilized during low traffic periods (especially during night) in the LTE-Advanced. http://hdl.handle.net/2117/17155 Title: On the use of mutual information at bit level for accurate link abstraction in LTE with incremental redundancy H-ARQ Authors: Olmos Bonafé, Juan José; Serra, Albert; Ruiz Boqué, Sílvia; Latif, Imran Abstract: Link abstraction methods are able to predict the BLER in multicarrier wideband systems using AMC techniques under multipath fading. The basic idea is to map the vector of the subcarrier SNR’s to a single scalar, the Effective SNR (ESNR), which is then used to predict the BLER. This procedure is important during real system operation, since the mobile terminal must report the Channel Quality Indicator (CQI) to the base station, and also for the system level simulators. In order to take into account H-ARQ, it is also interesting to predict the BLER after one or more IR retransmissions have happened. With IR H-ARQ there is an additional complexity, since the BLER performance of a given redundancy version (rv) depends on the SNR experienced by the receiver at current rv but also on the SNR of previously received rv's. We propose a novel link abstraction method that can predict the BLER with good accuracy in multipath fading and including the effects of H-ARQ retransmissions. The proposed method is based on estimating the mutual information between the transmitted bits and the received LLRs. We show that, by working at bit level, the effect of unequal error protection in 16 and 64QAM modulations is properly captured without resorting to any set of calibration constants. We also show how to reduce the set of reference BLER curves when working with multiple modulation and code schemes (MCS). Simulation results for LTE downlink with SISO transmission mode are included in the paper. Wed, 19 Dec 2012 15:11:25 GMT http://hdl.handle.net/2117/17155 2012-12-19T15:11:25Z Olmos Bonafé, Juan José; Serra, Albert; Ruiz Boqué, Sílvia; Latif, Imran no Link abstraction methods are able to predict the BLER in multicarrier wideband systems using AMC techniques under multipath fading. The basic idea is to map the vector of the subcarrier SNR’s to a single scalar, the Effective SNR (ESNR), which is then used to predict the BLER. This procedure is important during real system operation, since the mobile terminal must report the Channel Quality Indicator (CQI) to the base station, and also for the system level simulators. In order to take into account H-ARQ, it is also interesting to predict the BLER after one or more IR retransmissions have happened. With IR H-ARQ there is an additional complexity, since the BLER performance of a given redundancy version (rv) depends on the SNR experienced by the receiver at current rv but also on the SNR of previously received rv's. We propose a novel link abstraction method that can predict the BLER with good accuracy in multipath fading and including the effects of H-ARQ retransmissions. The proposed method is based on estimating the mutual information between the transmitted bits and the received LLRs. We show that, by working at bit level, the effect of unequal error protection in 16 and 64QAM modulations is properly captured without resorting to any set of calibration constants. We also show how to reduce the set of reference BLER curves when working with multiple modulation and code schemes (MCS). Simulation results for LTE downlink with SISO transmission mode are included in the paper. http://hdl.handle.net/2117/16573 Title: An analytical view of static intercell interference coordination techniques in OFDMA networks Authors: González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José Abstract: This paper presents a novel methodology to assess the downlink performance of static intercell interference coordination techniques in the context of OFDMA-based cellular networks. In the last few years, interference mitigation techniques have been considered a research topic of utmost importance since intercell interference is the main issue limiting the capacity of modern cellular technologies such as LTE and WiMAX. The methodology presented in this paper should be understood not only as an analytical shortcut to foresee overall network interference conditions but also a mean to properly establish bounds to parameters associated to static intercell interference techniques operation. Moreover, the analysis allows to take into account both local large scale fading particularities and mobile operators’ preferences. In this sense, results show how the resulting set of preferred operational points is in general operatordependent and hence, the usefulness of the proposed framework is established. Tue, 25 Sep 2012 17:48:55 GMT http://hdl.handle.net/2117/16573 2012-09-25T17:48:55Z González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José no This paper presents a novel methodology to assess the downlink performance of static intercell interference coordination techniques in the context of OFDMA-based cellular networks. In the last few years, interference mitigation techniques have been considered a research topic of utmost importance since intercell interference is the main issue limiting the capacity of modern cellular technologies such as LTE and WiMAX. The methodology presented in this paper should be understood not only as an analytical shortcut to foresee overall network interference conditions but also a mean to properly establish bounds to parameters associated to static intercell interference techniques operation. Moreover, the analysis allows to take into account both local large scale fading particularities and mobile operators’ preferences. In this sense, results show how the resulting set of preferred operational points is in general operatordependent and hence, the usefulness of the proposed framework is established. http://hdl.handle.net/2117/16572 Title: On the role of downlink control information in the provision of QoS for NRT services in LTE Authors: González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José Abstract: The provision of Quality of Service (QoS) to users of LTE networks depends to a large degree on the choice of an appropriate scheduling algorithm able to meet the requirements of mobile operators. Dynamic packet scheduling has been recognized as a key approach to maximize the utility of OFDMAbased systems due to its inherent ability to exploit the frequency selectiveness of wideband channels both in time and frequency domain. However, one of the main issues associated to dynamic scheduling is the high amount of signaling overhead required to provide users with resource allocation information. While the impact of control channel limitations on LTE VoIP capacity has been widely studied yet, tradeoffs associated to control channel usage and the provision of QoS for Non-Real Time (NRT) services has been basically omitted in current literature. In this paper, such tradeoffs have been addressed from several perspectives. Results show that the relationship between scheduling policies, offered levels of QoS (expressed in terms of guaranteed bit rates) and control channels capacity is not trivial and requires careful planning. Tue, 25 Sep 2012 17:35:34 GMT http://hdl.handle.net/2117/16572 2012-09-25T17:35:34Z González González, David; García Lozano, Mario; Ruiz Boqué, Sílvia; Olmos Bonafé, Juan José no The provision of Quality of Service (QoS) to users of LTE networks depends to a large degree on the choice of an appropriate scheduling algorithm able to meet the requirements of mobile operators. Dynamic packet scheduling has been recognized as a key approach to maximize the utility of OFDMAbased systems due to its inherent ability to exploit the frequency selectiveness of wideband channels both in time and frequency domain. However, one of the main issues associated to dynamic scheduling is the high amount of signaling overhead required to provide users with resource allocation information. While the impact of control channel limitations on LTE VoIP capacity has been widely studied yet, tradeoffs associated to control channel usage and the provision of QoS for Non-Real Time (NRT) services has been basically omitted in current literature. In this paper, such tradeoffs have been addressed from several perspectives. Results show that the relationship between scheduling policies, offered levels of QoS (expressed in terms of guaranteed bit rates) and control channels capacity is not trivial and requires careful planning.