Pub Date : 2016-09-01DOI: 10.1109/VTCFall.2016.7881217
C. Kundu, T. Ngatched, O. Dobre
In this paper, the secrecy of a cooperative system consisting of a single source, relay, destination and eavesdropper is analyzed. The threshold-selection decode-and-forward relay is considered, where the relay can correctly decode and forward only if it satisfies a threshold signal-to-noise ratio (SNR). Both destination and eavesdropper take advantage of the direct and relayed transmissions through maximal ratio diversity combining. The secrecy outage probability (SOP) and ergodic secrecy rate are derived in closed-form for different channel state information (CSI) availability. It was observed that when the required rate is low, having CSI knowledge is more advantageous than in the case of higher rate. An increase in the required threshold SNR at the relay can increase the SOP if the relayed link SNR is relatively higher than the direct link SNR. It was also shown that SOP cannot be improved beyond a certain value when keeping either dual-hop link average SNR fixed and increasing the other link SNR, whereas the ergodic secrecy rate can be increased by keeping the source to destination average SNR fixed.
{"title":"Secrecy Performance of Dual-Hop Threshold Relaying System with Diversity Reception","authors":"C. Kundu, T. Ngatched, O. Dobre","doi":"10.1109/VTCFall.2016.7881217","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7881217","url":null,"abstract":"In this paper, the secrecy of a cooperative system consisting of a single source, relay, destination and eavesdropper is analyzed. The threshold-selection decode-and-forward relay is considered, where the relay can correctly decode and forward only if it satisfies a threshold signal-to-noise ratio (SNR). Both destination and eavesdropper take advantage of the direct and relayed transmissions through maximal ratio diversity combining. The secrecy outage probability (SOP) and ergodic secrecy rate are derived in closed-form for different channel state information (CSI) availability. It was observed that when the required rate is low, having CSI knowledge is more advantageous than in the case of higher rate. An increase in the required threshold SNR at the relay can increase the SOP if the relayed link SNR is relatively higher than the direct link SNR. It was also shown that SOP cannot be improved beyond a certain value when keeping either dual-hop link average SNR fixed and increasing the other link SNR, whereas the ergodic secrecy rate can be increased by keeping the source to destination average SNR fixed.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"34 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81964865","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 : 2016-09-01DOI: 10.1109/VTCFall.2016.7881100
Chunling Peng, Fangwei Li, Huaping Liu
Existing finite field network coding (FFNC) can be applied in networks where all users have the same data rate and can thus use the same modulation type. In most practical scenarios, different users typically have different data rates. With simple changes such as zero-padding and repetition to the data sequences of different users received at relays, it is still possible to employ the existing FFNC scheme, but the network throughput and error performance will be compromised. In this paper, we design a network coding scheme for multiuser multiple-relay networks where users' data rates are different. Specifically, we develop a layered network coding approach that allows the use of the existing FFNC for each layer in a hierarchical structure and derive the corresponding decoding process. The bit error (BER) and computational complexity of the proposed scheme are derived. Because the proposed scheme could fully exploit the additional diversity gain from decoding the codewords in each layer separately, it achieves a better BER performance than the existing FFNC scheme, which is validated in simulation.
{"title":"Multi-Layer Network Coding for Multiuser Relay Networks with Non-Uniform-Rate Users","authors":"Chunling Peng, Fangwei Li, Huaping Liu","doi":"10.1109/VTCFall.2016.7881100","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7881100","url":null,"abstract":"Existing finite field network coding (FFNC) can be applied in networks where all users have the same data rate and can thus use the same modulation type. In most practical scenarios, different users typically have different data rates. With simple changes such as zero-padding and repetition to the data sequences of different users received at relays, it is still possible to employ the existing FFNC scheme, but the network throughput and error performance will be compromised. In this paper, we design a network coding scheme for multiuser multiple-relay networks where users' data rates are different. Specifically, we develop a layered network coding approach that allows the use of the existing FFNC for each layer in a hierarchical structure and derive the corresponding decoding process. The bit error (BER) and computational complexity of the proposed scheme are derived. Because the proposed scheme could fully exploit the additional diversity gain from decoding the codewords in each layer separately, it achieves a better BER performance than the existing FFNC scheme, which is validated in simulation.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"62 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79430486","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 : 2016-09-01DOI: 10.1109/VTCFall.2016.7881231
D. Jayakody, E. Rosnes
In this work, we propose a new technique of spatially-coupled low-density parity-check coding within a threshold-based lossy forwarding protocol for a multiple access relaying system. Here, block Rayleigh fading is assumed for all transmission links and error-free decoding at the relay is not required. Two schemes are presented in which the relay computes log-likelihood ratios (LLRs) of the network-coded symbols (from the sources) based on the received signals. By comparing the LLRs to a preset threshold, the relay decides to forward hard decisions when the network-coded symbol reliability is higher than the preset threshold. Otherwise, the relay decides to stay silent (first scheme) or to forward the LLRs to the destination (second scheme). Finally, we modify the LLR combining at the destination, based on an expression for the uncoded bit-error probability which is tailored to the proposed schemes. Simulation results demonstrate that the proposed relay protocol yields an improved bit-error rate performance compared to competitive schemes proposed in the literature.
{"title":"Spatially-Coupled LDPC Coding in Threshold-Based Lossy Forwarding Scheme","authors":"D. Jayakody, E. Rosnes","doi":"10.1109/VTCFall.2016.7881231","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7881231","url":null,"abstract":"In this work, we propose a new technique of spatially-coupled low-density parity-check coding within a threshold-based lossy forwarding protocol for a multiple access relaying system. Here, block Rayleigh fading is assumed for all transmission links and error-free decoding at the relay is not required. Two schemes are presented in which the relay computes log-likelihood ratios (LLRs) of the network-coded symbols (from the sources) based on the received signals. By comparing the LLRs to a preset threshold, the relay decides to forward hard decisions when the network-coded symbol reliability is higher than the preset threshold. Otherwise, the relay decides to stay silent (first scheme) or to forward the LLRs to the destination (second scheme). Finally, we modify the LLR combining at the destination, based on an expression for the uncoded bit-error probability which is tailored to the proposed schemes. Simulation results demonstrate that the proposed relay protocol yields an improved bit-error rate performance compared to competitive schemes proposed in the literature.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"64 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83746998","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 : 2016-09-01DOI: 10.1109/VTCFall.2016.7881580
T. Fernandes, M. Gomes, V. Silva, R. Dinis
The growing progress in wireless communication services lead to a demand in high data rates, spectral efficiency and flexibility requirements. The recently proposed Block- Windowed Burst Orthogonal Frequency Division Multiplexing (BWB-OFDM) transceiver proved to be a reliable alternative scheme to face these current demands. BWB-OFDM employs smoother, non- rectangular windows, allowing a power spectral density similar to the filtered OFDM approach; also, it packs together several OFDM symbols, with the addition of a sole zero- padding to accommodate the multipath channel's propagation delay. This means better overall power and spectral efficiencies. Nevertheless, the system has the same drawback of OFDM when transmitting over hostile channel conditions, such as deep fading in time-dispersive channels. To overcome this problem, a new Time-Interleaved BWB- OFDM (TIBWB- OFDM) transceiver is proposed. This scheme employs interleaving on the time-samples of each BWB- OFDM block, thus creating a sort of diversity at the frequency domain, aiming to preserve the data symbols severely corrupted by the channel's deep fades. The new TIBWB-OFDM transceiver presents considerable power gains relatively to the BWB-OFDM,while maintaining their spectral efficiency.
{"title":"Time-Interleaved Block-Windowed Burst OFDM","authors":"T. Fernandes, M. Gomes, V. Silva, R. Dinis","doi":"10.1109/VTCFall.2016.7881580","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7881580","url":null,"abstract":"The growing progress in wireless communication services lead to a demand in high data rates, spectral efficiency and flexibility requirements. The recently proposed Block- Windowed Burst Orthogonal Frequency Division Multiplexing (BWB-OFDM) transceiver proved to be a reliable alternative scheme to face these current demands. BWB-OFDM employs smoother, non- rectangular windows, allowing a power spectral density similar to the filtered OFDM approach; also, it packs together several OFDM symbols, with the addition of a sole zero- padding to accommodate the multipath channel's propagation delay. This means better overall power and spectral efficiencies. Nevertheless, the system has the same drawback of OFDM when transmitting over hostile channel conditions, such as deep fading in time-dispersive channels. To overcome this problem, a new Time-Interleaved BWB- OFDM (TIBWB- OFDM) transceiver is proposed. This scheme employs interleaving on the time-samples of each BWB- OFDM block, thus creating a sort of diversity at the frequency domain, aiming to preserve the data symbols severely corrupted by the channel's deep fades. The new TIBWB-OFDM transceiver presents considerable power gains relatively to the BWB-OFDM,while maintaining their spectral efficiency.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"55 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82599010","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 : 2016-09-01DOI: 10.1109/VTCFall.2016.7880878
Hongbin Liang, Lei Zheng, Wei Li, Qingchun Chen
Resource virtualization is considered as a potential technique to cope with the mushroomed multimedia services. With resource virtualization, physical resources are characterized as virtual resource shared by various Service Providers (SPs). In this paper, we focus on the virtual resource allocation problem for multimedia service in 5G network. The system rewards is maximized with the considerations of the system virtual resource consumption and the incomes generated from mobile users. To address this issue, a Multimedia Service Admission Model (MSAM) based on Semi-Markov Decision Process (SMDP) is proposed to characterize the system rewards. Then the steady-state probability and service request blocking probability are derived. Numerical results show that theoretic results are consistent with the simulation results.
{"title":"A SMDP Based Virtual Resource Allocation Model for Multimedia Services in 5G Network","authors":"Hongbin Liang, Lei Zheng, Wei Li, Qingchun Chen","doi":"10.1109/VTCFall.2016.7880878","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7880878","url":null,"abstract":"Resource virtualization is considered as a potential technique to cope with the mushroomed multimedia services. With resource virtualization, physical resources are characterized as virtual resource shared by various Service Providers (SPs). In this paper, we focus on the virtual resource allocation problem for multimedia service in 5G network. The system rewards is maximized with the considerations of the system virtual resource consumption and the incomes generated from mobile users. To address this issue, a Multimedia Service Admission Model (MSAM) based on Semi-Markov Decision Process (SMDP) is proposed to characterize the system rewards. Then the steady-state probability and service request blocking probability are derived. Numerical results show that theoretic results are consistent with the simulation results.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"60 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80533221","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 : 2016-09-01DOI: 10.1109/VTCFall.2016.7881958
Mark Adams, V. Bhargava
This paper presents the use of recursive least squares for online estimation of the self interference channel for an In Band Full Duplex communications link without the use of half duplex pilot signals. By using a long effective filter length it is possible to overcome the extra interference of the receieved signal, and it proves to be an effective way to estimate the channel in all scenarios, but it provides the greatest efficiency gain over current methods with a short channel coherence time. Recursive least squares estimation provides a way to take advantage of the constant knowledge of the transmitted signal to track the channel while consuming relatively few computational resources. Introducing online RLS estimation for In-Band Full Duplex communication provides a way to take advantage of the self interference cancellation gains from digital cancellation without introducing additional protocol overhead to the transmissions.
{"title":"Use of the Recursive Least Squares Filter for Self Interference Channel Estimation","authors":"Mark Adams, V. Bhargava","doi":"10.1109/VTCFall.2016.7881958","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7881958","url":null,"abstract":"This paper presents the use of recursive least squares for online estimation of the self interference channel for an In Band Full Duplex communications link without the use of half duplex pilot signals. By using a long effective filter length it is possible to overcome the extra interference of the receieved signal, and it proves to be an effective way to estimate the channel in all scenarios, but it provides the greatest efficiency gain over current methods with a short channel coherence time. Recursive least squares estimation provides a way to take advantage of the constant knowledge of the transmitted signal to track the channel while consuming relatively few computational resources. Introducing online RLS estimation for In-Band Full Duplex communication provides a way to take advantage of the self interference cancellation gains from digital cancellation without introducing additional protocol overhead to the transmissions.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"47 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80725202","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 : 2016-09-01DOI: 10.1109/VTCFall.2016.7881034
Ahmad El Assaad, Markus Krug, G. Fischer
In this paper, an algorithm for accurate distance estimation of a vehicle to a road side unit (RSU) in urban multipath environments is presented. The algorithm is based on spatial filtering using a uniform circular array (UCA) antenna and a cross correlation based time delay detection. The time base for the cross correlation is built using Global Navigation Satellite System (GNSS) based positioning. Furthermore, an algorithm for non- line-of-sight (NLOS) detection based on a fingerprinting technique is presented to identify shadowing situations. For evaluation purposes, a simulation for a vehicle following a straightway maneuver within an urban orthogonal traffic intersection scenario is carried out. The B1 line- of-sight (LOS) specified in WINNER II is used for multipath channel modeling. Simulation results show that the obtained distance estimation accuracy of a vehicle is better than 50cm within a radius of 500m around the traffic intersection origin and the proposed NLOS detection algorithm exhibits a 0% false alarm probability (FAP) within this range.
{"title":"Highly Accurate Distance Estimation Using Spatial Filtering and GNSS in Urban Environments","authors":"Ahmad El Assaad, Markus Krug, G. Fischer","doi":"10.1109/VTCFall.2016.7881034","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7881034","url":null,"abstract":"In this paper, an algorithm for accurate distance estimation of a vehicle to a road side unit (RSU) in urban multipath environments is presented. The algorithm is based on spatial filtering using a uniform circular array (UCA) antenna and a cross correlation based time delay detection. The time base for the cross correlation is built using Global Navigation Satellite System (GNSS) based positioning. Furthermore, an algorithm for non- line-of-sight (NLOS) detection based on a fingerprinting technique is presented to identify shadowing situations. For evaluation purposes, a simulation for a vehicle following a straightway maneuver within an urban orthogonal traffic intersection scenario is carried out. The B1 line- of-sight (LOS) specified in WINNER II is used for multipath channel modeling. Simulation results show that the obtained distance estimation accuracy of a vehicle is better than 50cm within a radius of 500m around the traffic intersection origin and the proposed NLOS detection algorithm exhibits a 0% false alarm probability (FAP) within this range.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"42 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83035314","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 : 2016-09-01DOI: 10.1109/VTCFall.2016.7881101
Kyong-Soo Cha, Dong-Min Kim, Min-Ro Park, M. Yoon, Jung-Pyo Hong
The greenhouse effect is getting worse in these days. To reduce this environmental problem, emission regulation in the automotive industries became strict. Accordingly, the automotive makers started to develop the environmental friendly vehicles such as the hybrid electric vehicle (HEV) and electric vehicle (EV). In the x-EV system, electric traction motor is the most important part act as the engine of the conventional vehicle. The design trend of the electric motor for EV traction is the high-speed low-torque with the reduction gear. For this reason, high speed operating condition should be considered in the design process. In this paper, some design factor study was done, considering both the electrical performance and the mechanical stress. Using these study results and response surface method (RSM) optimum design was conducted. From the optimum designed motor, mechanical stress simulation was done considering about the 15% margin of the maximum operating speed of the electric motor. Consequently, the multi-layered interior permanent magnet motor (IPMSM) design was done fulfill the electrical performance and the not exceeding the yield strength of the electrical steel sheet consist the electrical motor.
{"title":"Multipolar High-Speed IPMSM Design for EV Traction Considering Mechanical Stress","authors":"Kyong-Soo Cha, Dong-Min Kim, Min-Ro Park, M. Yoon, Jung-Pyo Hong","doi":"10.1109/VTCFall.2016.7881101","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7881101","url":null,"abstract":"The greenhouse effect is getting worse in these days. To reduce this environmental problem, emission regulation in the automotive industries became strict. Accordingly, the automotive makers started to develop the environmental friendly vehicles such as the hybrid electric vehicle (HEV) and electric vehicle (EV). In the x-EV system, electric traction motor is the most important part act as the engine of the conventional vehicle. The design trend of the electric motor for EV traction is the high-speed low-torque with the reduction gear. For this reason, high speed operating condition should be considered in the design process. In this paper, some design factor study was done, considering both the electrical performance and the mechanical stress. Using these study results and response surface method (RSM) optimum design was conducted. From the optimum designed motor, mechanical stress simulation was done considering about the 15% margin of the maximum operating speed of the electric motor. Consequently, the multi-layered interior permanent magnet motor (IPMSM) design was done fulfill the electrical performance and the not exceeding the yield strength of the electrical steel sheet consist the electrical motor.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"42 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75821740","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 : 2016-09-01DOI: 10.1109/VTCFall.2016.7880906
Yuyang Wang, K. Venugopal, A. Molisch, R. Heath
Millimeter wave (mmWave) networks are sensitive to blockages due to buildings in urban areas. This is critical for vehicle-to-infrastructure networks which are cellular networks designed to support emerging vehicular applications. Motivated by measurement and ray tracing results in urban microcells, instead of characterizing the pathloss by Euclidean distance, we calculate it by the weighted sum of segment length along the propagation path, i.e., Manhattan distance, and a certain corner loss at the intersections along the path. We analyze network performance by modeling the urban microcell network by a Manhattan Poisson line process. Our results show significant differences between Manhattan and Euclidean distance- based pathloss models. Assuming the receiver is associated with the base station (BS) with the smallest pathloss, we derive closed-form expression of the distribution of the associated link pathloss. We obtain the coverage probability and reveal the impacts of interference from the LOS and NLOS BSs. It is shown that in this scenario the interference from a NLOS parallel street is negligible.
{"title":"Analysis of Urban Millimeter Wave Microcellular Networks","authors":"Yuyang Wang, K. Venugopal, A. Molisch, R. Heath","doi":"10.1109/VTCFall.2016.7880906","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7880906","url":null,"abstract":"Millimeter wave (mmWave) networks are sensitive to blockages due to buildings in urban areas. This is critical for vehicle-to-infrastructure networks which are cellular networks designed to support emerging vehicular applications. Motivated by measurement and ray tracing results in urban microcells, instead of characterizing the pathloss by Euclidean distance, we calculate it by the weighted sum of segment length along the propagation path, i.e., Manhattan distance, and a certain corner loss at the intersections along the path. We analyze network performance by modeling the urban microcell network by a Manhattan Poisson line process. Our results show significant differences between Manhattan and Euclidean distance- based pathloss models. Assuming the receiver is associated with the base station (BS) with the smallest pathloss, we derive closed-form expression of the distribution of the associated link pathloss. We obtain the coverage probability and reveal the impacts of interference from the LOS and NLOS BSs. It is shown that in this scenario the interference from a NLOS parallel street is negligible.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"67 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81199442","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}
In this paper, we investigate the energy-aware data- offloading of mobile user (MU) which schedules its traffic demand to a macro Base Station (BS) and a small-cell access point (AP) simultaneously. For saving the usage of licensed spectrum, we consider that the MU uses unlicensed spectrum to offload data. The open access of unlicensed spectrum, however, results in that the MU's data offloading suffer from uncontrollable interference, which comprises the benefit of data offloading. We propose an outage-probability to quantify such an adverse influence and formulate a joint rate-splitting and power allocation problem to minimize a system-wise cost accounting for both the MU's power consumption and the BS's licensed channel usage. Despite the non-convexity of the joint optimization problem, we transform it into three rate- allocation problems under different cases and derive the respective optimal solutions, which yield the globally optimal solution for the original problem. Numerical results are provided to validate the optimal offloading-solution.
{"title":"Energy-Aware Optimal Data Offloading over Unlicensed Spectrums","authors":"Yuan Wu, Haohan Chai, L. Qian, Weidang Lu, Qinglin Zhao, Changsheng Yu","doi":"10.1109/VTCFall.2016.7880991","DOIUrl":"https://doi.org/10.1109/VTCFall.2016.7880991","url":null,"abstract":"In this paper, we investigate the energy-aware data- offloading of mobile user (MU) which schedules its traffic demand to a macro Base Station (BS) and a small-cell access point (AP) simultaneously. For saving the usage of licensed spectrum, we consider that the MU uses unlicensed spectrum to offload data. The open access of unlicensed spectrum, however, results in that the MU's data offloading suffer from uncontrollable interference, which comprises the benefit of data offloading. We propose an outage-probability to quantify such an adverse influence and formulate a joint rate-splitting and power allocation problem to minimize a system-wise cost accounting for both the MU's power consumption and the BS's licensed channel usage. Despite the non-convexity of the joint optimization problem, we transform it into three rate- allocation problems under different cases and derive the respective optimal solutions, which yield the globally optimal solution for the original problem. Numerical results are provided to validate the optimal offloading-solution.","PeriodicalId":6484,"journal":{"name":"2016 IEEE 84th Vehicular Technology Conference (VTC-Fall)","volume":"86 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80915721","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}