Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037271
Yahia A. Eldemerdash, O. Dobre
In this paper, an algorithm for the detection of the Alamouti-coded orthogonal frequency division multiplexing (AL-OFDM) signals is proposed. To the best of our knowledge, this is the first time in the literature when the detection of AL-OFDM signals used in recent WiMAX and LTE standards is investigated. The cross-correlation between the signals received with two antennas is studied as a detection feature, and its analytical closed-form expression obtained. These findings are further employed to develop the signal detection algorithm. The algorithm performance is investigated based on simulated standard signals. A good performance is achieved with a short sensing time and at low signal-to-noise ratios (SNRs). Additionally, the proposed algorithm requires neither information about the channel, modulation type, and noise power, nor timing synchronization.
{"title":"Second-order statistic-based detection of Alamouti-coded OFDM signals for cognitive radio","authors":"Yahia A. Eldemerdash, O. Dobre","doi":"10.1109/GLOCOM.2014.7037271","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037271","url":null,"abstract":"In this paper, an algorithm for the detection of the Alamouti-coded orthogonal frequency division multiplexing (AL-OFDM) signals is proposed. To the best of our knowledge, this is the first time in the literature when the detection of AL-OFDM signals used in recent WiMAX and LTE standards is investigated. The cross-correlation between the signals received with two antennas is studied as a detection feature, and its analytical closed-form expression obtained. These findings are further employed to develop the signal detection algorithm. The algorithm performance is investigated based on simulated standard signals. A good performance is achieved with a short sensing time and at low signal-to-noise ratios (SNRs). Additionally, the proposed algorithm requires neither information about the channel, modulation type, and noise power, nor timing synchronization.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"177 1","pages":"3038-3043"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86935523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037176
I. Bisio, F. Lavagetto, M. Marchese, A. Sciarrone
Telemedicine applications provide healthcare services through communications technologies overcoming the geographical separation between patients and caregivers. These services can be provided via wireless devices, such as smart-phones with dedicated applications. An interesting application concerns the so-called situation awareness algorithms and, in particular, the Activity Recognition (AR) aimed at tracking the physical activity (or movements) of patients that need a constant monitoring of their medical conditions. This work takes as reference an architecture applicable, but not limited to, patients suffering from Heart Failure (HF) and presents a performance comparison between AR approaches based on the accelerometer signal captured through the patients' smartphones. In more detail, the considered AR techniques apply two different classifiers used to decide the patients movements: a J48 decision tree and a Support Vector Machine (SVM). For each classifier, three different features sets, characterizing the accelerometer signal, have been employed. The performance are evaluated both in terms of accuracy-related metrics and time needed by each classifiers to perform the decision. The results show that SVM provides the best accuracy while the J48 requires less classification time.
{"title":"Comparison of situation awareness algorithms for remote health monitoring with smartphones","authors":"I. Bisio, F. Lavagetto, M. Marchese, A. Sciarrone","doi":"10.1109/GLOCOM.2014.7037176","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037176","url":null,"abstract":"Telemedicine applications provide healthcare services through communications technologies overcoming the geographical separation between patients and caregivers. These services can be provided via wireless devices, such as smart-phones with dedicated applications. An interesting application concerns the so-called situation awareness algorithms and, in particular, the Activity Recognition (AR) aimed at tracking the physical activity (or movements) of patients that need a constant monitoring of their medical conditions. This work takes as reference an architecture applicable, but not limited to, patients suffering from Heart Failure (HF) and presents a performance comparison between AR approaches based on the accelerometer signal captured through the patients' smartphones. In more detail, the considered AR techniques apply two different classifiers used to decide the patients movements: a J48 decision tree and a Support Vector Machine (SVM). For each classifier, three different features sets, characterizing the accelerometer signal, have been employed. The performance are evaluated both in terms of accuracy-related metrics and time needed by each classifiers to perform the decision. The results show that SVM provides the best accuracy while the J48 requires less classification time.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"74 1","pages":"2454-2459"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86994953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037320
Junho Lee, Gye-Tae Gil, Y. H. Lee
Hybrid multiple input multiple output (MIMO) systems consist of an analog beamformer with large antenna arrays followed by a digital MIMO processor. Channel estimation for hybrid MIMO systems in millimeter wave (mm-wave) communications is challenging because of the large antenna array and the low signal-to-noise ratio (SNR) before beamforming. In this paper, we propose an open-loop channel estimator for mm-wave hybrid MIMO systems exploiting the sparse nature of mm-wave channels. A sparse signal recovery problem is formulated for channel estimation and solved by the orthogonal matching pursuit (OMP) based methods. A modification of the OMP algorithm, called the multi-grid (MG) OMP, is proposed. It is shown that the MG-OMP can significantly reduce the computational load of the OMP method. A process for designing the training beams is also developed. Specifically, given the analog training beams the baseband processor for beam training is designed. Simulation results demonstrate the advantage of the OMP based methods over the conventional least squares (LS) method and the efficiency of the MG-OMP over the original OMP.
{"title":"Exploiting spatial sparsity for estimating channels of hybrid MIMO systems in millimeter wave communications","authors":"Junho Lee, Gye-Tae Gil, Y. H. Lee","doi":"10.1109/GLOCOM.2014.7037320","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037320","url":null,"abstract":"Hybrid multiple input multiple output (MIMO) systems consist of an analog beamformer with large antenna arrays followed by a digital MIMO processor. Channel estimation for hybrid MIMO systems in millimeter wave (mm-wave) communications is challenging because of the large antenna array and the low signal-to-noise ratio (SNR) before beamforming. In this paper, we propose an open-loop channel estimator for mm-wave hybrid MIMO systems exploiting the sparse nature of mm-wave channels. A sparse signal recovery problem is formulated for channel estimation and solved by the orthogonal matching pursuit (OMP) based methods. A modification of the OMP algorithm, called the multi-grid (MG) OMP, is proposed. It is shown that the MG-OMP can significantly reduce the computational load of the OMP method. A process for designing the training beams is also developed. Specifically, given the analog training beams the baseband processor for beam training is designed. Simulation results demonstrate the advantage of the OMP based methods over the conventional least squares (LS) method and the efficiency of the MG-OMP over the original OMP.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"41 1","pages":"3326-3331"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88028110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037277
T. Duong, Tran Trung Duy, M. Elkashlan, N. Tran, O. Dobre
In this paper, we propose physical layer security for cooperative cognitive radio networks (CCRNs) with relay selection in the presence of multiple primary users and multiple eavesdroppers. To be specific, we propose three relay selection schemes, namely, opportunistic relay selection (ORS), suboptimal relay selection (SoRS), and partial relay selection (PRS) for secured CCRNs, which are based on the availability of channel state information (CSI) at the receivers. For each approach, we derive exact and asymptotic expressions for the secrecy outage probability. Results show that under the assumption of perfect CSI, ORS outperforms both SoRS and PRS.
{"title":"Secured cooperative cognitive radio networks with relay selection","authors":"T. Duong, Tran Trung Duy, M. Elkashlan, N. Tran, O. Dobre","doi":"10.1109/GLOCOM.2014.7037277","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037277","url":null,"abstract":"In this paper, we propose physical layer security for cooperative cognitive radio networks (CCRNs) with relay selection in the presence of multiple primary users and multiple eavesdroppers. To be specific, we propose three relay selection schemes, namely, opportunistic relay selection (ORS), suboptimal relay selection (SoRS), and partial relay selection (PRS) for secured CCRNs, which are based on the availability of channel state information (CSI) at the receivers. For each approach, we derive exact and asymptotic expressions for the secrecy outage probability. Results show that under the assumption of perfect CSI, ORS outperforms both SoRS and PRS.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"63 1","pages":"3074-3079"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88206211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037570
Victor Y. Chen, Wei Wang, Qian Zhang
The surging deployment of WiFi hotspots in public places drives the blossoming of location-based services (LBSs) available. A recent measurement reveals that a large portion of the reported locations are either forged or superfluous, which calls attention to location authentication. However, existing authentication approaches breach user's location privacy, which is of wide concern of both individuals and governments. In this paper, we propose PriLA, a privacy-preserving location authentication protocol that facilitates location authentication without compromising user's location privacy in WiFi networks. PriLA exploits physical layer information, namely carrier frequency offset (CFO) and multipath profile, from user's frames. In particular, PriLA leverages CFO to secure wireless transmission between the mobile user and the access point (AP), and meanwhile authenticate the reported locations without leaking the exact location information based on the coarse-grained location proximity being extracted from user's multipath profile. Existing privacy preservation techniques on upper layers can be applied on top of PriLA to enable various applications. We have implemented PriLa on GNURadio/USRP platform and off-the-shelf Intel 5300 NIC. The experimental results demonstrate the practicality of CFO injection and accuracy of multipath profile based location authentication in a real-world environment.
{"title":"Privacy-preserving location authentication in WiFi with fine-grained physical layer information","authors":"Victor Y. Chen, Wei Wang, Qian Zhang","doi":"10.1109/GLOCOM.2014.7037570","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037570","url":null,"abstract":"The surging deployment of WiFi hotspots in public places drives the blossoming of location-based services (LBSs) available. A recent measurement reveals that a large portion of the reported locations are either forged or superfluous, which calls attention to location authentication. However, existing authentication approaches breach user's location privacy, which is of wide concern of both individuals and governments. In this paper, we propose PriLA, a privacy-preserving location authentication protocol that facilitates location authentication without compromising user's location privacy in WiFi networks. PriLA exploits physical layer information, namely carrier frequency offset (CFO) and multipath profile, from user's frames. In particular, PriLA leverages CFO to secure wireless transmission between the mobile user and the access point (AP), and meanwhile authenticate the reported locations without leaking the exact location information based on the coarse-grained location proximity being extracted from user's multipath profile. Existing privacy preservation techniques on upper layers can be applied on top of PriLA to enable various applications. We have implemented PriLa on GNURadio/USRP platform and off-the-shelf Intel 5300 NIC. The experimental results demonstrate the practicality of CFO injection and accuracy of multipath profile based location authentication in a real-world environment.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"30 6 1","pages":"4827-4832"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88383490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7036855
Giirkan Solmaz, K. Akkaya, D. Turgut
Wireless sensor networks with mobile sinks can be deployed for efficient handling of the events that may occur in a theme park. In such a case, the success of event handling depends on the positions of the mobile sinks and the selection of the most suitable sink to cover an event. While this problem can be solved by using the classical vertex p-center problem, such a solution does not guarantee connectivity among the mobile sinks. The connectivity among mobile sinks is crucial since they need to communicate to share information and perform collaborative event handling. In this paper, we introduce a new variant of vertex p-center problem which we name communication-constrained p-center problem. We propose an exact algorithm as a solution based on identifying connected subnets among the vertices. The performance of the proposed solution is validated through simulations with respect to other approaches as well as the unconstrained case.
{"title":"Communication-constrained p-center problem for event coverage in theme parks","authors":"Giirkan Solmaz, K. Akkaya, D. Turgut","doi":"10.1109/GLOCOM.2014.7036855","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7036855","url":null,"abstract":"Wireless sensor networks with mobile sinks can be deployed for efficient handling of the events that may occur in a theme park. In such a case, the success of event handling depends on the positions of the mobile sinks and the selection of the most suitable sink to cover an event. While this problem can be solved by using the classical vertex p-center problem, such a solution does not guarantee connectivity among the mobile sinks. The connectivity among mobile sinks is crucial since they need to communicate to share information and perform collaborative event handling. In this paper, we introduce a new variant of vertex p-center problem which we name communication-constrained p-center problem. We propose an exact algorithm as a solution based on identifying connected subnets among the vertices. The performance of the proposed solution is validated through simulations with respect to other approaches as well as the unconstrained case.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"50 1","pages":"486-491"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86128132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037050
Hieu Duy Nguyen, Rui Zhang, Sumei Sun
The rate maximization for the K-user interference channels (ICs) has been investigated extensively in the literature. However, the dual problem of minimizing the error probability with given signal constellations and/or data rates of the users is less exploited. In this paper, by utilizing the additional degrees of freedom attained from the improper signaling (versus the conventional proper signaling), we optimize the precoding matrices for the K-user single-input single-output (SISO) ICs to achieve minimal transmission symbol error rate (SER). Compared to conventional proper signaling as well as other state-of-the-art improper signaling designs, our proposed improper signaling scheme is shown to achieve notable SER improvement in SISO-ICs by simulations. Our study provides another viewpoint for optimizing transmissions in ICs and further justifies the practical benefit of improper signaling in interference-limited communication systems.
{"title":"On design of improper signaling for ser minimization in K-user interference channel","authors":"Hieu Duy Nguyen, Rui Zhang, Sumei Sun","doi":"10.1109/GLOCOM.2014.7037050","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037050","url":null,"abstract":"The rate maximization for the K-user interference channels (ICs) has been investigated extensively in the literature. However, the dual problem of minimizing the error probability with given signal constellations and/or data rates of the users is less exploited. In this paper, by utilizing the additional degrees of freedom attained from the improper signaling (versus the conventional proper signaling), we optimize the precoding matrices for the K-user single-input single-output (SISO) ICs to achieve minimal transmission symbol error rate (SER). Compared to conventional proper signaling as well as other state-of-the-art improper signaling designs, our proposed improper signaling scheme is shown to achieve notable SER improvement in SISO-ICs by simulations. Our study provides another viewpoint for optimizing transmissions in ICs and further justifies the practical benefit of improper signaling in interference-limited communication systems.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"1 1","pages":"1679-1684"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86535100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037205
Tran Kien Thuc, H. Tabassum, E. Hossain
Energy harvesting in cellular networks is an emerging technique to enhance the sustainability of power-constrained wireless devices. This paper considers the co-channel deployment of a macrocell overlaid with small cells. The small cell base stations (SBSs) harvest their energy from environment sources whereas the macro base station (MBS) uses conventional power supply. Given a stochastic energy arrival process, this paper derives a power control policy for the downlink transmission of both MBS and SBSs such that they can obtain an equilibrium of their own objectives on a long-term basis (e.g., maximizing the transmission rate for SBSs while maintaining the target signal-to-interference-plus-noise ratio (SINR) at the macro users) on a given transmission channel. To this end, we propose a single controller stochastic game and develop a power control policy as a solution of a quadratic programming problem. Numerical results demonstrate the significance of the developed optimal power control policy over the conventional fixed and random power control policies.
{"title":"A stochastic power control game for two-tier cellular networks with energy harvesting small cells","authors":"Tran Kien Thuc, H. Tabassum, E. Hossain","doi":"10.1109/GLOCOM.2014.7037205","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037205","url":null,"abstract":"Energy harvesting in cellular networks is an emerging technique to enhance the sustainability of power-constrained wireless devices. This paper considers the co-channel deployment of a macrocell overlaid with small cells. The small cell base stations (SBSs) harvest their energy from environment sources whereas the macro base station (MBS) uses conventional power supply. Given a stochastic energy arrival process, this paper derives a power control policy for the downlink transmission of both MBS and SBSs such that they can obtain an equilibrium of their own objectives on a long-term basis (e.g., maximizing the transmission rate for SBSs while maintaining the target signal-to-interference-plus-noise ratio (SINR) at the macro users) on a given transmission channel. To this end, we propose a single controller stochastic game and develop a power control policy as a solution of a quadratic programming problem. Numerical results demonstrate the significance of the developed optimal power control policy over the conventional fixed and random power control policies.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"15 1","pages":"2637-2642"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89091314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037196
P. Sarigiannidis, Athanasios Gkaliouris, V. Kakali, M. Louta, G. Papadimitriou, Petros Nicopolitidis, M. Obaidat
Power management has been advanced on a crucial factor in the design of modern access networks. Furthermore, the proliferation of optical networking in the last mile led major Telecom unions, such as the International Telecommunication Union (ITU), to emerge energy consumption as a critical objective of the next generation passive optical networks (NG-PONs). In particular, the standardization of the 10-gigabit-capable PON (XG-PON) entails well-defined specifications towards power management and energy reduction, especially regarding the power control of optical terminal devices such as the optical network units (ONUs). In this way, the optical line terminator (OLT) along with ONUs are able to cooperate with each other in order to succeed energy reduction, by applying doze or cyclic sleep periods to idle ONUs. However, the sleep period determination remains a quite challenging research area. In this study, we endeavor to provide XG-PON networks with an effective forecasting mechanism that is capable of estimating the time duration of the forthcoming sleep session. To this end, we apply the exponential smoothing technique to best estimate the sleep duration based on the monitoring time series observations. The obtained evaluation results sound quite promising, since the proposed model accomplishes to advance the trade-off between the energy reduction and network efficiency.
{"title":"On forecasting the ONU sleep period in XG-PON systems using exponential smoothing techniques","authors":"P. Sarigiannidis, Athanasios Gkaliouris, V. Kakali, M. Louta, G. Papadimitriou, Petros Nicopolitidis, M. Obaidat","doi":"10.1109/GLOCOM.2014.7037196","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037196","url":null,"abstract":"Power management has been advanced on a crucial factor in the design of modern access networks. Furthermore, the proliferation of optical networking in the last mile led major Telecom unions, such as the International Telecommunication Union (ITU), to emerge energy consumption as a critical objective of the next generation passive optical networks (NG-PONs). In particular, the standardization of the 10-gigabit-capable PON (XG-PON) entails well-defined specifications towards power management and energy reduction, especially regarding the power control of optical terminal devices such as the optical network units (ONUs). In this way, the optical line terminator (OLT) along with ONUs are able to cooperate with each other in order to succeed energy reduction, by applying doze or cyclic sleep periods to idle ONUs. However, the sleep period determination remains a quite challenging research area. In this study, we endeavor to provide XG-PON networks with an effective forecasting mechanism that is capable of estimating the time duration of the forthcoming sleep session. To this end, we apply the exponential smoothing technique to best estimate the sleep duration based on the monitoring time series observations. The obtained evaluation results sound quite promising, since the proposed model accomplishes to advance the trade-off between the energy reduction and network efficiency.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"1 1","pages":"2580-2585"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89165962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/GLOCOM.2014.7037365
Congmin Fan, Y. Zhang, Xiaojun Yuan
Featured by centralized processing and cloud based infrastructure, Cloud Radio Access Network (C-RAN) is a promising solution to achieve an unprecedented system capacity in future wireless cellular networks. The huge capacity gain mainly comes from the centralized and coordinated signal processing at the cloud server. However, full-scale coordination in a large-scale C-RAN requires the processing of very large channel matrices, leading to high computational complexity and channel estimation overhead. To resolve this challenge, we show in this paper that the channel matrices can be greatly sparsified without substantially compromising the system capacity. Through rigorous analysis, we derive a simple threshold-based channel matrix sparsification approach. Based on this approach, for reasonably large networks, the non-zero entries in the channel matrix can be reduced to a very low percentage (say 0.13% ~ 2%) by compromising only 5% of SINR. This means each RRH only needs to obtain the CSI of a small number of closest users, resulting in a significant reduction in the channel estimation overhead. On the other hand, the high sparsity of the channel matrix allows us to design detection algorithms that are scalable in the sense that the average computational complexity per user does not grow with the network size.
{"title":"Scalable coordinated uplink processing in cloud radio access networks","authors":"Congmin Fan, Y. Zhang, Xiaojun Yuan","doi":"10.1109/GLOCOM.2014.7037365","DOIUrl":"https://doi.org/10.1109/GLOCOM.2014.7037365","url":null,"abstract":"Featured by centralized processing and cloud based infrastructure, Cloud Radio Access Network (C-RAN) is a promising solution to achieve an unprecedented system capacity in future wireless cellular networks. The huge capacity gain mainly comes from the centralized and coordinated signal processing at the cloud server. However, full-scale coordination in a large-scale C-RAN requires the processing of very large channel matrices, leading to high computational complexity and channel estimation overhead. To resolve this challenge, we show in this paper that the channel matrices can be greatly sparsified without substantially compromising the system capacity. Through rigorous analysis, we derive a simple threshold-based channel matrix sparsification approach. Based on this approach, for reasonably large networks, the non-zero entries in the channel matrix can be reduced to a very low percentage (say 0.13% ~ 2%) by compromising only 5% of SINR. This means each RRH only needs to obtain the CSI of a small number of closest users, resulting in a significant reduction in the channel estimation overhead. On the other hand, the high sparsity of the channel matrix allows us to design detection algorithms that are scalable in the sense that the average computational complexity per user does not grow with the network size.","PeriodicalId":6492,"journal":{"name":"2014 IEEE Global Communications Conference","volume":"112 1","pages":"3591-3596"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80759662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}