Pub Date : 2010-05-23DOI: 10.1109/ICC.2010.5502437
Junni Zou, Chong Tan, Ruifeng Zhang, H. Xiong
This paper studies the power consumption performance and resource allocation optimization in wireless video sensor networks. Network coding based multipath routing, network flow control and video encoding bit rate are jointly optimized, aiming to maximize the network lifetime at a given power budget and video quality requirement. Importantly, to concretely measure the network coding power utilized on error recovery, a generalized power consumption model for network coding is first developed in this paper. Through the Lagrange dual and subgradient approach, a fully decentralized algorithm is proposed to solve the target convex optimization problem. Numerical results validate the convergence and performance of the proposed algorithm.
{"title":"Modeling and Optimization of Network Lifetime in Wireless Video Sensor Networks","authors":"Junni Zou, Chong Tan, Ruifeng Zhang, H. Xiong","doi":"10.1109/ICC.2010.5502437","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502437","url":null,"abstract":"This paper studies the power consumption performance and resource allocation optimization in wireless video sensor networks. Network coding based multipath routing, network flow control and video encoding bit rate are jointly optimized, aiming to maximize the network lifetime at a given power budget and video quality requirement. Importantly, to concretely measure the network coding power utilized on error recovery, a generalized power consumption model for network coding is first developed in this paper. Through the Lagrange dual and subgradient approach, a fully decentralized algorithm is proposed to solve the target convex optimization problem. Numerical results validate the convergence and performance of the proposed algorithm.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"14 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86324777","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501818
M. Wolkerstorfer, D. Statovci, T. Nordström
We investigate a novel cross-layer optimization problem for jointly performing dynamic spectrum management (DSM) and periodic rate-scheduling in time. The large number of carriers used in digital subscriber lines (DSL) makes DSM a large-scale optimization problem for which dual optimization is a commonly used method. The duality-gap which potentially accompanies the dual optimization for non-convex problems is typically assumed to be small enough to be neglected. Also, previous theoretical results show a vanishing duality-gap as the number of subcarriers approaches infinity. We will bound the potential performance improvements that can be achieved by the additional rate-scheduling procedure. This bound is found to depend on the duality-gap in the physical layer DSM problem. Furthermore, we will derive bounds on the duality-gap of the two most important optimization problems in DSL, namely the maximization of the weighted sum-rate and the minimization of the weighted sum-power. These bounds are derived for a finite number of subcarriers and are also applicable to the respective problems in orthogonal frequency division multiplex (OFDM) systems.
{"title":"Duality-Gap Bounds for Multi-Carrier Systems and Their Application to Periodic Scheduling","authors":"M. Wolkerstorfer, D. Statovci, T. Nordström","doi":"10.1109/ICC.2010.5501818","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501818","url":null,"abstract":"We investigate a novel cross-layer optimization problem for jointly performing dynamic spectrum management (DSM) and periodic rate-scheduling in time. The large number of carriers used in digital subscriber lines (DSL) makes DSM a large-scale optimization problem for which dual optimization is a commonly used method. The duality-gap which potentially accompanies the dual optimization for non-convex problems is typically assumed to be small enough to be neglected. Also, previous theoretical results show a vanishing duality-gap as the number of subcarriers approaches infinity. We will bound the potential performance improvements that can be achieved by the additional rate-scheduling procedure. This bound is found to depend on the duality-gap in the physical layer DSM problem. Furthermore, we will derive bounds on the duality-gap of the two most important optimization problems in DSL, namely the maximization of the weighted sum-rate and the minimization of the weighted sum-power. These bounds are derived for a finite number of subcarriers and are also applicable to the respective problems in orthogonal frequency division multiplex (OFDM) systems.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"40 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86544852","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502155
Lu Lu, Ming Xiao, M. Skoglund, L. Rasmussen, Gang Wu, Shaoqian Li
We investigate the design and use of systematic binary deterministic rateless (BDR) codes for information transmission over block-erasure broadcast channels. BDR codes are designed to obtain a level of maximal distance separable (MDS) properties, making these codes ideal for the considered broadcast scenario. For a certain number of encoded redundancy blocks, we derive an expression for the probability that the MDS properties are maintained. Moreover, if limited feedback is available, we extend the BDR coding protocol to further improve the system performance. Numerical results show that for a finite number of source blocks and as the number of users grows the proposed systematic BDR codes performs significantly better than LT codes. The proposed schemes with feedback have better performance than traditional ARQ schemes.
{"title":"Efficient Wireless Broadcasting Based on Systematic Binary Deterministic Rateless Codes","authors":"Lu Lu, Ming Xiao, M. Skoglund, L. Rasmussen, Gang Wu, Shaoqian Li","doi":"10.1109/ICC.2010.5502155","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502155","url":null,"abstract":"We investigate the design and use of systematic binary deterministic rateless (BDR) codes for information transmission over block-erasure broadcast channels. BDR codes are designed to obtain a level of maximal distance separable (MDS) properties, making these codes ideal for the considered broadcast scenario. For a certain number of encoded redundancy blocks, we derive an expression for the probability that the MDS properties are maintained. Moreover, if limited feedback is available, we extend the BDR coding protocol to further improve the system performance. Numerical results show that for a finite number of source blocks and as the number of users grows the proposed systematic BDR codes performs significantly better than LT codes. The proposed schemes with feedback have better performance than traditional ARQ schemes.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"51 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82898718","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502689
J. Nsenga, A. Bourdoux, F. Horlin
Multi-antenna architectures, where beamforming processing is shared between analog and digital, are of great interest for future multi-Gbps wireless systems operating at 60 GHz. In this spectrum band, wireless systems can integrate large antenna arrays in a very small volume thanks to a wavelength of about 5 mm and thus provide the required gain to meet the severe link budget. However, the cost and power consumption of an analog front-end (AFE) chain, that carries out translation between radio frequency (RF) and digital baseband, are too high at 60 GHz to afford one AFE for each antenna. In this paper, we consider low cost multi-antenna architectures with a lower number of AFE chains than antenna elements. We propose a joint design of transmit-receive mixed analog/digital beamformers that aim at maximizing the received average signal-to-noise-ratio (SNR). The proposed scheme shows better performance than state-of-art solutions, which combine antenna selection techniques and digital beamforming.
{"title":"Mixed Analog/Digital Beamforming for 60 GHz MIMO Frequency Selective Channels","authors":"J. Nsenga, A. Bourdoux, F. Horlin","doi":"10.1109/ICC.2010.5502689","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502689","url":null,"abstract":"Multi-antenna architectures, where beamforming processing is shared between analog and digital, are of great interest for future multi-Gbps wireless systems operating at 60 GHz. In this spectrum band, wireless systems can integrate large antenna arrays in a very small volume thanks to a wavelength of about 5 mm and thus provide the required gain to meet the severe link budget. However, the cost and power consumption of an analog front-end (AFE) chain, that carries out translation between radio frequency (RF) and digital baseband, are too high at 60 GHz to afford one AFE for each antenna. In this paper, we consider low cost multi-antenna architectures with a lower number of AFE chains than antenna elements. We propose a joint design of transmit-receive mixed analog/digital beamformers that aim at maximizing the received average signal-to-noise-ratio (SNR). The proposed scheme shows better performance than state-of-art solutions, which combine antenna selection techniques and digital beamforming.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"21 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82611998","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501936
M. Renzo, H. Haas
In this paper, we develop an analytical framework for analyzing the performance of wireless systems adopting the recently proposed Space Shift Keying (SSK) modulation scheme. More specifically, we investigate the performance of a 2-by-1 MISO (Multiple-Input-Single-Output) system setup with Maximum-Likelihood (ML) detection at the receiver. The exact Average Bit Error Probability (ABEP) over correlated and non-identically distributed Nakagami-m fading channels is computed in closed-form. Numerical results will show that the performance of SSK modulation is significantly affected by the characteristics of fading channels, e.g., channel correlation, fading severity, and power imbalance among the wireless links. Analytical frameworks and findings will also be substantiated via Monte Carlo simulations.
{"title":"On the Performance of SSK Modulation over Correlated Nakagami-m Fading Channels","authors":"M. Renzo, H. Haas","doi":"10.1109/ICC.2010.5501936","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501936","url":null,"abstract":"In this paper, we develop an analytical framework for analyzing the performance of wireless systems adopting the recently proposed Space Shift Keying (SSK) modulation scheme. More specifically, we investigate the performance of a 2-by-1 MISO (Multiple-Input-Single-Output) system setup with Maximum-Likelihood (ML) detection at the receiver. The exact Average Bit Error Probability (ABEP) over correlated and non-identically distributed Nakagami-m fading channels is computed in closed-form. Numerical results will show that the performance of SSK modulation is significantly affected by the characteristics of fading channels, e.g., channel correlation, fading severity, and power imbalance among the wireless links. Analytical frameworks and findings will also be substantiated via Monte Carlo simulations.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"38 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86683671","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502212
Jun-Bae Seo, Victor C. M. Leung
This paper examines throughput and delay performances of multipacket reception (MPR) slotted ALOHA systems with the exponential backoff (EB) algorithm which consists of an initial transmission probability, exponentially decaying factor and a maximum number of backoff stages. We assume a finite population model and the saturated traffic condition where every terminal always has a packet to transmit. To show the general impacts of the EB algorithm's parameters on the system performance, we consider two MPR channels. In the first channel, all the packets transmitted cannot be successfully received, if the number of packets simultaneously transmitted exceeds a predefined threshold. In the second one, some of packets concurrently transmitted can be probabilistically received (captured). In numerical studies, we show how to adjust the parameters of EB algorithm given the MPR channel in order to achieve close-to-maximal system throughput, and discuss fair channel use.
{"title":"Analysis of an Exponential Backoff Algorithm for Multipacket Reception Slotted ALOHA Systems","authors":"Jun-Bae Seo, Victor C. M. Leung","doi":"10.1109/ICC.2010.5502212","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502212","url":null,"abstract":"This paper examines throughput and delay performances of multipacket reception (MPR) slotted ALOHA systems with the exponential backoff (EB) algorithm which consists of an initial transmission probability, exponentially decaying factor and a maximum number of backoff stages. We assume a finite population model and the saturated traffic condition where every terminal always has a packet to transmit. To show the general impacts of the EB algorithm's parameters on the system performance, we consider two MPR channels. In the first channel, all the packets transmitted cannot be successfully received, if the number of packets simultaneously transmitted exceeds a predefined threshold. In the second one, some of packets concurrently transmitted can be probabilistically received (captured). In numerical studies, we show how to adjust the parameters of EB algorithm given the MPR channel in order to achieve close-to-maximal system throughput, and discuss fair channel use.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"50 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89202644","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502352
Bo Su, Changxing Pei, Kuang Xu, Honggang Wang, Bin Wang
In this paper, we derive the general expressions of the throughput capacity scaling of mobile ad hoc networks (MANETs), and find that the strategy of an individual node determines the throughput of an MANET. We show that optimal strategies that maximize the throughput of the network can exist. Based on a game theoretic approach, we further show that the optimal strategies constitute Nash equilibria.
{"title":"Capacity Scaling of Mobile Ad Hoc Networks","authors":"Bo Su, Changxing Pei, Kuang Xu, Honggang Wang, Bin Wang","doi":"10.1109/ICC.2010.5502352","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502352","url":null,"abstract":"In this paper, we derive the general expressions of the throughput capacity scaling of mobile ad hoc networks (MANETs), and find that the strategy of an individual node determines the throughput of an MANET. We show that optimal strategies that maximize the throughput of the network can exist. Based on a game theoretic approach, we further show that the optimal strategies constitute Nash equilibria.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"25 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89220534","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501932
K. Illanko, A. Anpalagan, D. Androutsos
This paper presents a simple synchronous distributed power allocation algorithm that maximizes the total transmission rate of a number of radios operating in an unlicensed band, with either a total power constraint or individual power constraints. The redistribution of power by the algorithm also results in a fairer rate distribution. The algorithm is not based on Game theory or Lagrangian dual. Rather it uses the sensitivity of each user's rate to changes in the power levels of all users in the system, to steer the power distribution towards the global maximum sum rate. The algorithm's complexity scales with the number of users in the system. Simulation results demonstrate that the algorithm does converge to the global maximum sum rate and, at the same time, redistributes the power among the users to achieve a more equitable rate distribution. Results of the algorithm are also compared with solutions based on Game theory.
{"title":"An Optimal and Fair Distributed Algorithm for Power Allocation for Radios Coexisting in Unlicensed Spectra","authors":"K. Illanko, A. Anpalagan, D. Androutsos","doi":"10.1109/ICC.2010.5501932","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501932","url":null,"abstract":"This paper presents a simple synchronous distributed power allocation algorithm that maximizes the total transmission rate of a number of radios operating in an unlicensed band, with either a total power constraint or individual power constraints. The redistribution of power by the algorithm also results in a fairer rate distribution. The algorithm is not based on Game theory or Lagrangian dual. Rather it uses the sensitivity of each user's rate to changes in the power levels of all users in the system, to steer the power distribution towards the global maximum sum rate. The algorithm's complexity scales with the number of users in the system. Simulation results demonstrate that the algorithm does converge to the global maximum sum rate and, at the same time, redistributes the power among the users to achieve a more equitable rate distribution. Results of the algorithm are also compared with solutions based on Game theory.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"5 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88834374","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 : 2010-05-23DOI: 10.1109/ICC.2010.5501928
Chung Shue Chen, F. Baccelli
In this work, we develop mathematical and algorithmic tools for the self-optimization of mobile cellular networks. Scalable algorithms which are based on local measurements and do not require heavy coordination among the wireless devices are proposed. We focus on the optimization of transmit power and of user association. The method is applicable to both joint and separate optimizations. The global utility minimized is linked to potential delay fairness. The distributed algorithm adaptively updates the system parameters and achieves global optimality by measuring SINR and interference. It is built on Gibbs' sampler and offers a unified framework that can be easily reused for different purposes. Simulation results demonstrate the effectiveness of the algorithm.
{"title":"Self-Optimization in Mobile Cellular Networks: Power Control and User Association","authors":"Chung Shue Chen, F. Baccelli","doi":"10.1109/ICC.2010.5501928","DOIUrl":"https://doi.org/10.1109/ICC.2010.5501928","url":null,"abstract":"In this work, we develop mathematical and algorithmic tools for the self-optimization of mobile cellular networks. Scalable algorithms which are based on local measurements and do not require heavy coordination among the wireless devices are proposed. We focus on the optimization of transmit power and of user association. The method is applicable to both joint and separate optimizations. The global utility minimized is linked to potential delay fairness. The distributed algorithm adaptively updates the system parameters and achieves global optimality by measuring SINR and interference. It is built on Gibbs' sampler and offers a unified framework that can be easily reused for different purposes. Simulation results demonstrate the effectiveness of the algorithm.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"22 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88845106","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 : 2010-05-23DOI: 10.1109/ICC.2010.5502090
Omar A. Nasr, B. Daneshrad
Two fundamental problems related to multi-carrier modulation are considered in this paper. The first is finding the best modulation schemes in all subcarriers to minimize the total energy consumption required to send a given number of bits between two wireless nodes. The second is finding the best modulation schemes to maximize the number of bits transmitted between two nodes under total energy constraint. Discrete bit loading algorithms have been used to solve both problems over frequency selective channels. None of these algorithms takes the circuit energy into consideration. In this paper, we introduce new discrete bit loading algorithms to solve both problems with total energy defined as the sum of transmission energy and circuit energy. Compared to the conventional discrete bit loading algorithms, the new algorithms can achieve savings in the order of 9 dB in the energy minimization problem. 180% increase in the number of transmitted bits can also be achieved with the same total energy when compared to the existing algorithms.
{"title":"Circuit-Energy Aware Discrete Bit Loading","authors":"Omar A. Nasr, B. Daneshrad","doi":"10.1109/ICC.2010.5502090","DOIUrl":"https://doi.org/10.1109/ICC.2010.5502090","url":null,"abstract":"Two fundamental problems related to multi-carrier modulation are considered in this paper. The first is finding the best modulation schemes in all subcarriers to minimize the total energy consumption required to send a given number of bits between two wireless nodes. The second is finding the best modulation schemes to maximize the number of bits transmitted between two nodes under total energy constraint. Discrete bit loading algorithms have been used to solve both problems over frequency selective channels. None of these algorithms takes the circuit energy into consideration. In this paper, we introduce new discrete bit loading algorithms to solve both problems with total energy defined as the sum of transmission energy and circuit energy. Compared to the conventional discrete bit loading algorithms, the new algorithms can achieve savings in the order of 9 dB in the energy minimization problem. 180% increase in the number of transmitted bits can also be achieved with the same total energy when compared to the existing algorithms.","PeriodicalId":6405,"journal":{"name":"2010 IEEE International Conference on Communications","volume":"5 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2010-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83830349","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}
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