Pub Date : 2017-05-01DOI: 10.23919/WIOPT.2017.7959891
S. Bayhan, Liang Zheng, Jiasi Chen, M. D. Francesco, J. Kangasharju, M. Chiang
With growing data demand and the current dearth of spectrum, mobile operators are looking for new frequency bands to satisfy data-hungry users. One promising avenue of expansion is TV white spaces, which are currently available to secondary users as long as they do not interfere with primary (i.e., incumbent) users. In this work, we explore the benefits of offloading cellular traffic onto TV white spaces. We develop an analytical model and efficient algorithms to assign users to the cellular network or white space channels by considering their channel gains, multi-user interference on white space channels, and the cost of switching between different networks. We perform extensive data-driven simulations in two representative urban scenarios based on publicly available datasets. Our results show that white spaces can increase capacity by 16–62%, depending on the environment, but careful network selection is necessary to ensure that maximum capacity gains are realized. Moreover, we show that white spaces provide a significant benefit in serving indoor users where cellular channel conditions are poor. Specifically, our algorithms can offload up to 40% of cellular traffic to white spaces for indoor scenarios.
{"title":"Improving cellular capacity with white space offloading","authors":"S. Bayhan, Liang Zheng, Jiasi Chen, M. D. Francesco, J. Kangasharju, M. Chiang","doi":"10.23919/WIOPT.2017.7959891","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959891","url":null,"abstract":"With growing data demand and the current dearth of spectrum, mobile operators are looking for new frequency bands to satisfy data-hungry users. One promising avenue of expansion is TV white spaces, which are currently available to secondary users as long as they do not interfere with primary (i.e., incumbent) users. In this work, we explore the benefits of offloading cellular traffic onto TV white spaces. We develop an analytical model and efficient algorithms to assign users to the cellular network or white space channels by considering their channel gains, multi-user interference on white space channels, and the cost of switching between different networks. We perform extensive data-driven simulations in two representative urban scenarios based on publicly available datasets. Our results show that white spaces can increase capacity by 16–62%, depending on the environment, but careful network selection is necessary to ensure that maximum capacity gains are realized. Moreover, we show that white spaces provide a significant benefit in serving indoor users where cellular channel conditions are poor. Specifically, our algorithms can offload up to 40% of cellular traffic to white spaces for indoor scenarios.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"11 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91185435","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959886
P. Spentzouris, I. Koutsopoulos
Mobile location-based advertising has seen a lot of progress recently. We study the problem of optimal user targeting and monetization through advertising, from the point of view of the owner of a venue such as a shopping mall, an urban shopping district or an airport. The fundamental distinguishing characteristic of advertising in this setup is that the probability that the user will respond to an ad depends on timeliness of ad projection, hence it is important to target a mobile user with an appropriate ad or offer at the right time. A set of mobile users roam around the venue. Each user is profiled in terms of preferences based on prior visits. The system knows estimated instantaneous locations of users in the venue, e.g. through WiFi access point connectivity. A machine-learning model is used to derive a per-user time-varying probability of response to an ad, which depends on the relevance of the ad (store) to the user profile and on the time-varying physical proximity of the user to the store. Each store has a set of available ads, and each time the user responds to a projected ad, an amount is paid by the store to the venue owner. We use a stochastic-optimization framework based on Lyapunov optimization to address the problem of advertisement selection and allocation for maximizing the long-term average revenue of the venue owner subject to: (i) a constraint on maximum average ad projection rate per user for preventing user saturation, and (ii) a long-term average budget constraint for each store. We derive an algorithm that operates on a time slot basis by solving a simple assignment problem with instantaneous user locations while being agnostic to user mobility statistics. We test our algorithm with a real dataset of check-ins from Foursquare, complemented with data from user questionnaires. Our approach results in substantial improvement in revenue compared to approaches that are location- or relevance-agnostic.
{"title":"A Stochastic optimization framework for personalized location-based mobile advertising","authors":"P. Spentzouris, I. Koutsopoulos","doi":"10.23919/WIOPT.2017.7959886","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959886","url":null,"abstract":"Mobile location-based advertising has seen a lot of progress recently. We study the problem of optimal user targeting and monetization through advertising, from the point of view of the owner of a venue such as a shopping mall, an urban shopping district or an airport. The fundamental distinguishing characteristic of advertising in this setup is that the probability that the user will respond to an ad depends on timeliness of ad projection, hence it is important to target a mobile user with an appropriate ad or offer at the right time. A set of mobile users roam around the venue. Each user is profiled in terms of preferences based on prior visits. The system knows estimated instantaneous locations of users in the venue, e.g. through WiFi access point connectivity. A machine-learning model is used to derive a per-user time-varying probability of response to an ad, which depends on the relevance of the ad (store) to the user profile and on the time-varying physical proximity of the user to the store. Each store has a set of available ads, and each time the user responds to a projected ad, an amount is paid by the store to the venue owner. We use a stochastic-optimization framework based on Lyapunov optimization to address the problem of advertisement selection and allocation for maximizing the long-term average revenue of the venue owner subject to: (i) a constraint on maximum average ad projection rate per user for preventing user saturation, and (ii) a long-term average budget constraint for each store. We derive an algorithm that operates on a time slot basis by solving a simple assignment problem with instantaneous user locations while being agnostic to user mobility statistics. We test our algorithm with a real dataset of check-ins from Foursquare, complemented with data from user questionnaires. Our approach results in substantial improvement in revenue compared to approaches that are location- or relevance-agnostic.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"57 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87195663","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959901
Zhiyuan Wang, Lin Gao, Jianwei Huang
Rollover data plans are attractive to mobile users by allowing them to keep their unused data for future use, and hence has been widely implemented by Mobile Network Operators (MNOs) around the world. In this work, we formulate a three-stage Stackelberg game to analyze the interactions between an MNO and its subscribed users under both traditional and rollover data plans. Specifically, in Stage I, the MNO decides which data plan(s) to implement; In Stage II, the MNO decides the price(s) of the data plan(s) to maximize its expected revenue; In Stage III, users make their individual subscription decisions to maximize their expected payoffs. Our analysis shows that in general, high evaluation users are more likely to choose the rollover data plan than medium evaluation users. More precisely, as the network substitutability increases, high evaluation users tend to choose the rollover data plan, while medium evaluation users tend to choose the traditional data plan. We further prove that the MNO can achieve the maximum revenue by only providing the rollover data plan (without bundling with the traditional data plan). Numerical results show that the rollover data plan can increase not only the MNO's revenue but also the users' payoffs (and hence the social welfare) comparing with the traditional data plan. We also compare two rollover data plans that differ in whether the rollover data is consumed prior to monthly data cap, and show that allowing the rollover data to be consumed before the monthly data cap is more beneficial to both users and the MNO.
{"title":"Pricing optimization of rollover data plan","authors":"Zhiyuan Wang, Lin Gao, Jianwei Huang","doi":"10.23919/WIOPT.2017.7959901","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959901","url":null,"abstract":"Rollover data plans are attractive to mobile users by allowing them to keep their unused data for future use, and hence has been widely implemented by Mobile Network Operators (MNOs) around the world. In this work, we formulate a three-stage Stackelberg game to analyze the interactions between an MNO and its subscribed users under both traditional and rollover data plans. Specifically, in Stage I, the MNO decides which data plan(s) to implement; In Stage II, the MNO decides the price(s) of the data plan(s) to maximize its expected revenue; In Stage III, users make their individual subscription decisions to maximize their expected payoffs. Our analysis shows that in general, high evaluation users are more likely to choose the rollover data plan than medium evaluation users. More precisely, as the network substitutability increases, high evaluation users tend to choose the rollover data plan, while medium evaluation users tend to choose the traditional data plan. We further prove that the MNO can achieve the maximum revenue by only providing the rollover data plan (without bundling with the traditional data plan). Numerical results show that the rollover data plan can increase not only the MNO's revenue but also the users' payoffs (and hence the social welfare) comparing with the traditional data plan. We also compare two rollover data plans that differ in whether the rollover data is consumed prior to monthly data cap, and show that allowing the rollover data to be consumed before the monthly data cap is more beneficial to both users and the MNO.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"42 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72769100","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959916
Jia Liu, E. Bentley
Massive MIMO and millimeter-wave communication (mmWave) have recently emerged as two key technologies for building 5G wireless networks and beyond. To reconcile the conflict between the large antenna arrays and the limited amount of radio-frequency (RF) chains in mmWave systems, the so-called hybrid beamforming becomes a promising solution and has received a great deal of attention in recent years. However, existing research on hybrid beamforming focused mostly on the physical layer or signal processing aspects. So far, there is a lack of theoretical understanding on how hybrid beamforming could affect mmWave network optimization. In this paper, we consider the impacts of hybrid beamforming on utility-optimality and queueing delay in mmWave cellular network optimization. Our contributions in this paper are three-fold: i) we develop a joint hybrid beamforming and congestion control algorithmic framework for mmWave network utility maximization; ii) we reveal a pseudoconvexity structure in the hybrid beamforming scheduling problem, which leads to simplified analog beamforming protocol design; and iii) we theoretically characterize the scalings of utility-optimality and delay with respect to channel state information (CSI) accuracy in digital beamforming.
{"title":"Hybrid-beamforming-based millimeter-wave cellular network optimization","authors":"Jia Liu, E. Bentley","doi":"10.23919/WIOPT.2017.7959916","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959916","url":null,"abstract":"Massive MIMO and millimeter-wave communication (mmWave) have recently emerged as two key technologies for building 5G wireless networks and beyond. To reconcile the conflict between the large antenna arrays and the limited amount of radio-frequency (RF) chains in mmWave systems, the so-called hybrid beamforming becomes a promising solution and has received a great deal of attention in recent years. However, existing research on hybrid beamforming focused mostly on the physical layer or signal processing aspects. So far, there is a lack of theoretical understanding on how hybrid beamforming could affect mmWave network optimization. In this paper, we consider the impacts of hybrid beamforming on utility-optimality and queueing delay in mmWave cellular network optimization. Our contributions in this paper are three-fold: i) we develop a joint hybrid beamforming and congestion control algorithmic framework for mmWave network utility maximization; ii) we reveal a pseudoconvexity structure in the hybrid beamforming scheduling problem, which leads to simplified analog beamforming protocol design; and iii) we theoretically characterize the scalings of utility-optimality and delay with respect to channel state information (CSI) accuracy in digital beamforming.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"44 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79091196","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959918
Rong Du, C. Fischione, Ming Xiao
The lifetime of a wireless sensor network (WSN) is limited by the lifetime of the individual sensor nodes. A promising technique to extend the lifetime of the nodes is wireless energy transfer. The WSN lifetime can also be extended by exploiting the redundancy in the nodes' deployment, which allows the implementation of duty-cycling mechanisms. In this paper, the joint problem of optimal sensor node deployment and WET scheduling is investigated. Such a problem is formulated as an integer optimization whose solution is challenging due to the binary decision variables and non-linear constraints. To solve the problem, an approach based on two steps is proposed. First, the necessary condition for which the WSN is immortal is established. Based on this result, an algorithm to solve the node deployment problem is developed. Then, the optimal WET scheduling is given by a scheduling algorithm. The WSN is shown to be immortal from a networking point of view, given the optimal deployment and WET scheduling. Theoretical results show that the proposed algorithm achieves the optimal node deployment in terms of the number of deployed nodes. In the simulation, it is shown that the proposed algorithm reduces significantly the number of nodes to deploy compared to a random-based approach. The results also suggest that, under such deployment, the optimal scheduling and WET can make WSNs immortal.
{"title":"Joint node deployment and wireless energy transfer scheduling for immortal sensor networks","authors":"Rong Du, C. Fischione, Ming Xiao","doi":"10.23919/WIOPT.2017.7959918","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959918","url":null,"abstract":"The lifetime of a wireless sensor network (WSN) is limited by the lifetime of the individual sensor nodes. A promising technique to extend the lifetime of the nodes is wireless energy transfer. The WSN lifetime can also be extended by exploiting the redundancy in the nodes' deployment, which allows the implementation of duty-cycling mechanisms. In this paper, the joint problem of optimal sensor node deployment and WET scheduling is investigated. Such a problem is formulated as an integer optimization whose solution is challenging due to the binary decision variables and non-linear constraints. To solve the problem, an approach based on two steps is proposed. First, the necessary condition for which the WSN is immortal is established. Based on this result, an algorithm to solve the node deployment problem is developed. Then, the optimal WET scheduling is given by a scheduling algorithm. The WSN is shown to be immortal from a networking point of view, given the optimal deployment and WET scheduling. Theoretical results show that the proposed algorithm achieves the optimal node deployment in terms of the number of deployed nodes. In the simulation, it is shown that the proposed algorithm reduces significantly the number of nodes to deploy compared to a random-based approach. The results also suggest that, under such deployment, the optimal scheduling and WET can make WSNs immortal.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"52 2 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86773722","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959910
M. Fasoulakis, A. Traganitis, A. Ephremides
We consider the Gaussian interference channel as a non-cooperative game taking into account the cost of the transmission. We study the conditions of the existence of a pure Nash equilibrium. Particularly, for the many-user case we give sufficient conditions that lead to a Nash equilibrium, and for the two-user case we exhaustively describe the conditions of the existence and the uniqueness of a pure Nash equilibrium and we show the existence of best-response dynamics that converge to one of them.
{"title":"The Gaussian interference channel revisited as a non-cooperative game with transmission cost","authors":"M. Fasoulakis, A. Traganitis, A. Ephremides","doi":"10.23919/WIOPT.2017.7959910","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959910","url":null,"abstract":"We consider the Gaussian interference channel as a non-cooperative game taking into account the cost of the transmission. We study the conditions of the existence of a pure Nash equilibrium. Particularly, for the many-user case we give sufficient conditions that lead to a Nash equilibrium, and for the two-user case we exhaustively describe the conditions of the existence and the uniqueness of a pure Nash equilibrium and we show the existence of best-response dynamics that converge to one of them.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"71 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85893318","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959903
Xiaowen Gong, N. Shroff
Mobile crowd sensing has found a variety of applications (e.g., spectrum sensing, environmental monitoring) by leveraging the "wisdom" of a potentially large crowd of mobile users. An important metric of a crowd sensing task is data accuracy, which relies on the qualities of the participating users' data (e.g., users' received SNRs for measuring a transmitter's transmit signal strength). However, the quality of a user can be its private information (which, e.g., may depend on the user's location) that it can manipulate to its own advantage, which can mislead the crowd sensing requester about the knowledge of the data's accuracy. This issue is exacerbated by the fact that the user can also manipulate its effort made in the crowd sensing task, which is a hidden action that could result in the requester having incorrect knowledge of the data's accuracy. In this paper, we devise truthful crowd sensing mechanisms for Quality and Effort Elicitation (QEE), which incentivize strategic users to truthfully reveal their private qualities and truthfully make efforts as desired by the requester. The QEE mechanisms achieve the truthful design by overcoming the intricate dependency of a user's data on its private quality and hidden effort. Under the QEE mechanisms, we show that the crowd sensing requester's optimal (CO) effort assignment assigns effort only to the best user that has the smallest "virtual valuation", which depends on the user's quality and the quality's distribution. We also show that, as the number of users increases, the performance gap between the CO effort assignment and the socially optimal effort assignment decreases, and converges to 0 asymptotically. We further show that while the requester's payoff and the social welfare attained by the CO effort assignment both increase as the number of users increases, interestingly, the corresponding users' payoffs can decrease. Simulation results demonstrate the truthfulness of the QEE mechanisms and the system efficiency of the CO effort assignment.
{"title":"Truthful mobile crowdsensing for strategic users with private qualities","authors":"Xiaowen Gong, N. Shroff","doi":"10.23919/WIOPT.2017.7959903","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959903","url":null,"abstract":"Mobile crowd sensing has found a variety of applications (e.g., spectrum sensing, environmental monitoring) by leveraging the \"wisdom\" of a potentially large crowd of mobile users. An important metric of a crowd sensing task is data accuracy, which relies on the qualities of the participating users' data (e.g., users' received SNRs for measuring a transmitter's transmit signal strength). However, the quality of a user can be its private information (which, e.g., may depend on the user's location) that it can manipulate to its own advantage, which can mislead the crowd sensing requester about the knowledge of the data's accuracy. This issue is exacerbated by the fact that the user can also manipulate its effort made in the crowd sensing task, which is a hidden action that could result in the requester having incorrect knowledge of the data's accuracy. In this paper, we devise truthful crowd sensing mechanisms for Quality and Effort Elicitation (QEE), which incentivize strategic users to truthfully reveal their private qualities and truthfully make efforts as desired by the requester. The QEE mechanisms achieve the truthful design by overcoming the intricate dependency of a user's data on its private quality and hidden effort. Under the QEE mechanisms, we show that the crowd sensing requester's optimal (CO) effort assignment assigns effort only to the best user that has the smallest \"virtual valuation\", which depends on the user's quality and the quality's distribution. We also show that, as the number of users increases, the performance gap between the CO effort assignment and the socially optimal effort assignment decreases, and converges to 0 asymptotically. We further show that while the requester's payoff and the social welfare attained by the CO effort assignment both increase as the number of users increases, interestingly, the corresponding users' payoffs can decrease. Simulation results demonstrate the truthfulness of the QEE mechanisms and the system efficiency of the CO effort assignment.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"52 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85764453","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959889
N. Prasad, S. Rangarajan
We consider network utility maximization problems over heterogeneous cellular networks (HetNets) that permit dual connectivity. Dual connectivity (DC) is a feature that targets emerging practical HetNet deployments that will comprise of non-ideal (higher latency) connections between transmission nodes, and has been recently introduced to the LTE-Advanced standard. DC allows for a user to be simultaneously served by a macro node as well as one other (typically micro or pico) node and requires relatively coarser level coordination among serving nodes. For such a DC enabled HetNet we comprehensively analyze the problem of determining an optimal user association that maximizes the weighted sum rate system utility subject to per-user rate constraints, over all feasible associations. Here, in any feasible association each user can be associated with (i.e., configured to receive data from) any one macro node (in a given set of macro nodes) and any one pico node that lies in the chosen macro node's coverage area. We show that, remarkably, this problem can be cast as a non-monotone submodular set function maximization problem, which allows us to construct a constant-factor approximation algorithm. We then consider the proportional fairness (PF) system utility and characterize the PF optimal resource allocation. This enables us to construct an efficient algorithm to determine an association that is optimal up-to an additive constant. We then validate the performance of our algorithms via numerical results.
{"title":"Exploiting dual connectivity in heterogeneous cellular networks","authors":"N. Prasad, S. Rangarajan","doi":"10.23919/WIOPT.2017.7959889","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959889","url":null,"abstract":"We consider network utility maximization problems over heterogeneous cellular networks (HetNets) that permit dual connectivity. Dual connectivity (DC) is a feature that targets emerging practical HetNet deployments that will comprise of non-ideal (higher latency) connections between transmission nodes, and has been recently introduced to the LTE-Advanced standard. DC allows for a user to be simultaneously served by a macro node as well as one other (typically micro or pico) node and requires relatively coarser level coordination among serving nodes. For such a DC enabled HetNet we comprehensively analyze the problem of determining an optimal user association that maximizes the weighted sum rate system utility subject to per-user rate constraints, over all feasible associations. Here, in any feasible association each user can be associated with (i.e., configured to receive data from) any one macro node (in a given set of macro nodes) and any one pico node that lies in the chosen macro node's coverage area. We show that, remarkably, this problem can be cast as a non-monotone submodular set function maximization problem, which allows us to construct a constant-factor approximation algorithm. We then consider the proportional fairness (PF) system utility and characterize the PF optimal resource allocation. This enables us to construct an efficient algorithm to determine an association that is optimal up-to an additive constant. We then validate the performance of our algorithms via numerical results.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"8 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82462312","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959932
T. O’Farrell, Ravinder Singh, Q. Bai, K. L. Ford, R. Langley, M. Beach, E. Arabi, C. Gamlath, K. Morris
This invited paper considers a key next step in the design of radio architectures aimed at supporting low energy consumption in 5G heterogeneous radio access networks. State-of-the-art mobile radios usually require one RF transceiver per standard, each working separately at any given time. Software defined radios, while spanning a wide range of standards and frequency bands, also work separately at any specific time. In 5G radio access networks, where continuous, multiband connectivity is envisaged, this conventional radio architecture results in high network power consumption. In this paper, we propose the novel concept of a concurrent multiband frequency-agile radio (CM-FARAD) architecture, which simultaneously supports multiple standards and frequency bands using a single, tunable transceiver. We discuss the subsystem radio design approaches for enabling the CM-FARAD architecture, including antennas, power amplifiers, low noise amplifiers and analogue to digital converters. A working prototype of a dual-band CM-FARAD test-bed is also presented together with measured salient performance characteristics.
{"title":"Tunable, concurrent multiband, single chain radio architecture for low energy 5G-RANs","authors":"T. O’Farrell, Ravinder Singh, Q. Bai, K. L. Ford, R. Langley, M. Beach, E. Arabi, C. Gamlath, K. Morris","doi":"10.23919/WIOPT.2017.7959932","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959932","url":null,"abstract":"This invited paper considers a key next step in the design of radio architectures aimed at supporting low energy consumption in 5G heterogeneous radio access networks. State-of-the-art mobile radios usually require one RF transceiver per standard, each working separately at any given time. Software defined radios, while spanning a wide range of standards and frequency bands, also work separately at any specific time. In 5G radio access networks, where continuous, multiband connectivity is envisaged, this conventional radio architecture results in high network power consumption. In this paper, we propose the novel concept of a concurrent multiband frequency-agile radio (CM-FARAD) architecture, which simultaneously supports multiple standards and frequency bands using a single, tunable transceiver. We discuss the subsystem radio design approaches for enabling the CM-FARAD architecture, including antennas, power amplifiers, low noise amplifiers and analogue to digital converters. A working prototype of a dual-band CM-FARAD test-bed is also presented together with measured salient performance characteristics.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"40 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88697752","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 : 2017-05-01DOI: 10.23919/WIOPT.2017.7959920
M. Sharma, C. Murthy, R. Vaze
In this paper, we consider a point-to-point link between an energy harvesting transmitter and receiver, where neither node has the information about the battery state or energy availability at the other node. We consider a model where data is successfully delivered only in slots where both nodes are active. Energy loss occurs whenever one node turns on while the other node is in sleep mode. In each slot, based on their own energy availability, the transmitter and receiver need to independently decide whether or not to turn on, with the aim of maximizing the long-term time-average throughput. We present an upper bound on the throughput achievable by analyzing a genie-aided system that has noncausal knowledge of the energy arrivals at both the nodes. Next, we propose an online policy requiring an occasional one-bit feedback whose throughput is within one bit of the upper bound, asymptotically in the battery size. In order to further reduce the feedback required, we propose a time-dilated version of the online policy. As the time dilation gets large, this policy does not require any feedback and achieves the upper bound asymptotically in the battery size. Inspired by this, we also propose a near-optimal fully uncoordinated policy. We use Monte Carlo simulations to validate our theoretical results and illustrate the performance of the proposed policies.
{"title":"On distributed power control for uncoordinated dual energy harvesting links: Performance bounds and near-optimal policies","authors":"M. Sharma, C. Murthy, R. Vaze","doi":"10.23919/WIOPT.2017.7959920","DOIUrl":"https://doi.org/10.23919/WIOPT.2017.7959920","url":null,"abstract":"In this paper, we consider a point-to-point link between an energy harvesting transmitter and receiver, where neither node has the information about the battery state or energy availability at the other node. We consider a model where data is successfully delivered only in slots where both nodes are active. Energy loss occurs whenever one node turns on while the other node is in sleep mode. In each slot, based on their own energy availability, the transmitter and receiver need to independently decide whether or not to turn on, with the aim of maximizing the long-term time-average throughput. We present an upper bound on the throughput achievable by analyzing a genie-aided system that has noncausal knowledge of the energy arrivals at both the nodes. Next, we propose an online policy requiring an occasional one-bit feedback whose throughput is within one bit of the upper bound, asymptotically in the battery size. In order to further reduce the feedback required, we propose a time-dilated version of the online policy. As the time dilation gets large, this policy does not require any feedback and achieves the upper bound asymptotically in the battery size. Inspired by this, we also propose a near-optimal fully uncoordinated policy. We use Monte Carlo simulations to validate our theoretical results and illustrate the performance of the proposed policies.","PeriodicalId":6630,"journal":{"name":"2017 15th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt)","volume":"35 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90051755","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}