Pub Date : 2017-11-01DOI: 10.1109/LATINCOM.2017.8240183
J. T. Gutierrez-Mena, C. Gutiérrez, J. V. Castillo
In this paper, we present a channel model that characterizes the non-stationarities of small-scale multipleinput multiple-output (MIMO) vehicle-to-vehicle (V2V) double-Rayleigh fading channels that arise from the temporal variations of the propagation delays. The analysis of the correlation properties of the proposed channel model is the main objetive of our paper. To achieve this goal, we derive an analytical expression for the space-time-frequency cross-correlation function (STF-CCF) following a geometrical plane-wave propagation (PWP) framework. An important feature of this expression is that it does not depend on a particular arrangement of the interfering objects (IOs) in the propagation scenario. Furthermore, a closedform expression of the STF-CCF is derived for the particular case of the geometrical two-rings model. The analytical and simulation results show that the elements of the MIMO channel matrix are non-wide-sense stationary (non-WSS) random processes both in the time and the frequency domains, as well as pairwise jointly non-WSS both in the time and the frequency domains.
{"title":"Geometrical modeling of non-stationary double-Rayleigh fading channels for MIMO vehicle-to-vehicle communications","authors":"J. T. Gutierrez-Mena, C. Gutiérrez, J. V. Castillo","doi":"10.1109/LATINCOM.2017.8240183","DOIUrl":"https://doi.org/10.1109/LATINCOM.2017.8240183","url":null,"abstract":"In this paper, we present a channel model that characterizes the non-stationarities of small-scale multipleinput multiple-output (MIMO) vehicle-to-vehicle (V2V) double-Rayleigh fading channels that arise from the temporal variations of the propagation delays. The analysis of the correlation properties of the proposed channel model is the main objetive of our paper. To achieve this goal, we derive an analytical expression for the space-time-frequency cross-correlation function (STF-CCF) following a geometrical plane-wave propagation (PWP) framework. An important feature of this expression is that it does not depend on a particular arrangement of the interfering objects (IOs) in the propagation scenario. Furthermore, a closedform expression of the STF-CCF is derived for the particular case of the geometrical two-rings model. The analytical and simulation results show that the elements of the MIMO channel matrix are non-wide-sense stationary (non-WSS) random processes both in the time and the frequency domains, as well as pairwise jointly non-WSS both in the time and the frequency domains.","PeriodicalId":190644,"journal":{"name":"2017 IEEE 9th Latin-American Conference on Communications (LATINCOM)","volume":"127 1-3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123574718","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 : 2017-11-01DOI: 10.1109/LATINCOM.2017.8240156
H. Sampaio, S. Motoyama
A greenhouse monitoring system using hierarchical wireless sensor network (WSN) is presented in this paper. The main parameters required to monitor and control a greenhouse are air humidity and temperature, ground moisture and environment lightness. For the data gathering of these parameters, a hierarchical WSN is presented in this work. In this configuration, the sensors, aggregated with all gathering functionalities, processing and wireless data transmission capabilities, denoted as sensor nodes, are in the lowest level. The router nodes are provided in the middle level to transmit data from sensor nodes to a controller named coordinator node. The coordinator node, in the highest level, is used to communicate with a central base, where all data received are analyzed. The details of a simple implementation of this monitoring system are presented. Many tests are carried out and the results showed that developed monitoring system is working well.
{"title":"Implementation of a greenhouse monitoring system using hierarchical wireless sensor network","authors":"H. Sampaio, S. Motoyama","doi":"10.1109/LATINCOM.2017.8240156","DOIUrl":"https://doi.org/10.1109/LATINCOM.2017.8240156","url":null,"abstract":"A greenhouse monitoring system using hierarchical wireless sensor network (WSN) is presented in this paper. The main parameters required to monitor and control a greenhouse are air humidity and temperature, ground moisture and environment lightness. For the data gathering of these parameters, a hierarchical WSN is presented in this work. In this configuration, the sensors, aggregated with all gathering functionalities, processing and wireless data transmission capabilities, denoted as sensor nodes, are in the lowest level. The router nodes are provided in the middle level to transmit data from sensor nodes to a controller named coordinator node. The coordinator node, in the highest level, is used to communicate with a central base, where all data received are analyzed. The details of a simple implementation of this monitoring system are presented. Many tests are carried out and the results showed that developed monitoring system is working well.","PeriodicalId":190644,"journal":{"name":"2017 IEEE 9th Latin-American Conference on Communications (LATINCOM)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123862340","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 : 2017-11-01DOI: 10.1109/LATINCOM.2017.8240152
David Zabala-Blanco, G. Campuzano, César A. Azurdia-Meza, S. M. Sánchez
It is well-know that carrier frequency offset in the subcarriers of orthogonal frequency division multiplexing (OFDM) leads to intercarrier interference (ICI); therefore, system degradation occurs. Nevertheless, this issue may effectively be mitigated via the pulse shaping filter method. In this manuscript, we present the improved double jump linear combination (IDJLC) function. With the goal of minimizing the bit error rate (BER), we then optimize it by employing its extra design parameters. Finally, our filter is compared with some of the best and most recent filters found in the literature in terms of ICI, signal to interference ratio, signal to noise ratio and normalized frequency offset requirements at a BER threshold of 10∼3, frequency profile, and average elapsed time. In general, the performance of the system is improved by using the IDJLC pulse.
{"title":"Performance enhancement in OFDM systems with ICI utilizing the improved double jump linear combination pulse","authors":"David Zabala-Blanco, G. Campuzano, César A. Azurdia-Meza, S. M. Sánchez","doi":"10.1109/LATINCOM.2017.8240152","DOIUrl":"https://doi.org/10.1109/LATINCOM.2017.8240152","url":null,"abstract":"It is well-know that carrier frequency offset in the subcarriers of orthogonal frequency division multiplexing (OFDM) leads to intercarrier interference (ICI); therefore, system degradation occurs. Nevertheless, this issue may effectively be mitigated via the pulse shaping filter method. In this manuscript, we present the improved double jump linear combination (IDJLC) function. With the goal of minimizing the bit error rate (BER), we then optimize it by employing its extra design parameters. Finally, our filter is compared with some of the best and most recent filters found in the literature in terms of ICI, signal to interference ratio, signal to noise ratio and normalized frequency offset requirements at a BER threshold of 10∼3, frequency profile, and average elapsed time. In general, the performance of the system is improved by using the IDJLC pulse.","PeriodicalId":190644,"journal":{"name":"2017 IEEE 9th Latin-American Conference on Communications (LATINCOM)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133827961","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 : 2017-11-01DOI: 10.1109/LATINCOM.2017.8240148
J. A. Icedo-Navarro, R. E. Tapia-Rodriguez, A. García-Juárez, Jose R. Noriega-Luna, A. G. Correa-Mena, L. A. González-Mondragón, I. Zaldívar-Huerta
In this paper a practical application of an electrooptical communication system based on external modulation is reported. The sixteen ATSC TV-channels located at 2.4 GHz, were transmitted over a 30 km of standard optical fiber. The transmitted TV-signal uses Single-Side Band Full Carrier (SSBFC) modulation, allowing in this way an adequate management of the transmitted power and the bandwidth. The efficient use of the available bandwidth of the electro optical system is achieved using two Low-Pass Filters (LPFs). Two seventh-order microstrip Chebyshev LPFs are designed and fabricated to select the signals to be transmitted through a point-to-point Passive Optical Network (PON). The experimental results allow this electro-optical communication system located in the field of radio over optical fiber shows that can be used as an alternative means for transmission of multimedia data with potential applications in a PON.
{"title":"Transmission system for digital TV-signal distribution through a passive optical network in the microwave S-band","authors":"J. A. Icedo-Navarro, R. E. Tapia-Rodriguez, A. García-Juárez, Jose R. Noriega-Luna, A. G. Correa-Mena, L. A. González-Mondragón, I. Zaldívar-Huerta","doi":"10.1109/LATINCOM.2017.8240148","DOIUrl":"https://doi.org/10.1109/LATINCOM.2017.8240148","url":null,"abstract":"In this paper a practical application of an electrooptical communication system based on external modulation is reported. The sixteen ATSC TV-channels located at 2.4 GHz, were transmitted over a 30 km of standard optical fiber. The transmitted TV-signal uses Single-Side Band Full Carrier (SSBFC) modulation, allowing in this way an adequate management of the transmitted power and the bandwidth. The efficient use of the available bandwidth of the electro optical system is achieved using two Low-Pass Filters (LPFs). Two seventh-order microstrip Chebyshev LPFs are designed and fabricated to select the signals to be transmitted through a point-to-point Passive Optical Network (PON). The experimental results allow this electro-optical communication system located in the field of radio over optical fiber shows that can be used as an alternative means for transmission of multimedia data with potential applications in a PON.","PeriodicalId":190644,"journal":{"name":"2017 IEEE 9th Latin-American Conference on Communications (LATINCOM)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116098264","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 : 2017-11-01DOI: 10.1109/LATINCOM.2017.8240184
L. M. M. Zorello, M. A. T. Rojas, M. Coupechoux, R. Vaze, T. Carvalho
In this paper, we consider a Device-to-Device (D2D) cellular network in which idle users can work as relays between cell users and the base station to improve their data rate. The relaying induces a cost for the User Equipment Relays (UER), that should be compensated with a payment from the mobile operator so that UERs accept to offer the service. The problem hence arises for the operator to match cell users and UERs at a reasonable cost and increasing the data rate. In this context, we consider the requirements of truthfulness, budget feasibility and acceptance of online scenarios to compare ON algorithm, which considers all constraints, with other three algorithms that were not built to respect all of them, Hungarian, Threshold and Online Weighted Knapsack (OWK). We observed that ON algorithm is the best in terms of execution time; however, it does not scale well considering the number of matched edges, requiring modifications in its selection criteria. In addition, we noticed that OWK algorithm has appealing properties and, if it were modified to be truthful and to reduce its complexity, it would present the best results.
{"title":"Performance analysis of online matching algorithms for D2D communications","authors":"L. M. M. Zorello, M. A. T. Rojas, M. Coupechoux, R. Vaze, T. Carvalho","doi":"10.1109/LATINCOM.2017.8240184","DOIUrl":"https://doi.org/10.1109/LATINCOM.2017.8240184","url":null,"abstract":"In this paper, we consider a Device-to-Device (D2D) cellular network in which idle users can work as relays between cell users and the base station to improve their data rate. The relaying induces a cost for the User Equipment Relays (UER), that should be compensated with a payment from the mobile operator so that UERs accept to offer the service. The problem hence arises for the operator to match cell users and UERs at a reasonable cost and increasing the data rate. In this context, we consider the requirements of truthfulness, budget feasibility and acceptance of online scenarios to compare ON algorithm, which considers all constraints, with other three algorithms that were not built to respect all of them, Hungarian, Threshold and Online Weighted Knapsack (OWK). We observed that ON algorithm is the best in terms of execution time; however, it does not scale well considering the number of matched edges, requiring modifications in its selection criteria. In addition, we noticed that OWK algorithm has appealing properties and, if it were modified to be truthful and to reduce its complexity, it would present the best results.","PeriodicalId":190644,"journal":{"name":"2017 IEEE 9th Latin-American Conference on Communications (LATINCOM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129123713","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 : 2017-11-01DOI: 10.1109/LATINCOM.2017.8240160
Sadaf Moaveninejad, Atul Kumar, Davide Scazzoli, Alessandro Piti, M. Magarini, S. Bregni, G. Verticale
Low voltage, in-home power-line communications (PLC) networks allow direct communication between smart meters (SM) and in-home devices (IHD). In order to minimize security issues, in many deployment scenarios transmission takes place only towards the IHD to display consumption data, with no backwards channel. As a result, channel estimation is difficult and it is necessary to use robust transmission techniques to mitigate the effect of the impulsive noise within the PLC channel. Performance of such system must be evaluated by taking into account realistic interference and channel models for a broad range of configurations. In this work we focus on performance in terms of bit error rate (BER) of a narrowband PLC (NB-PLC) operating in the CENELEC-C band (125–140 kHz) taking into account realistic noise models. Our system is based on binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK) modulation.
{"title":"BER evaluation of post-meter PLC services in CENELEC-C band","authors":"Sadaf Moaveninejad, Atul Kumar, Davide Scazzoli, Alessandro Piti, M. Magarini, S. Bregni, G. Verticale","doi":"10.1109/LATINCOM.2017.8240160","DOIUrl":"https://doi.org/10.1109/LATINCOM.2017.8240160","url":null,"abstract":"Low voltage, in-home power-line communications (PLC) networks allow direct communication between smart meters (SM) and in-home devices (IHD). In order to minimize security issues, in many deployment scenarios transmission takes place only towards the IHD to display consumption data, with no backwards channel. As a result, channel estimation is difficult and it is necessary to use robust transmission techniques to mitigate the effect of the impulsive noise within the PLC channel. Performance of such system must be evaluated by taking into account realistic interference and channel models for a broad range of configurations. In this work we focus on performance in terms of bit error rate (BER) of a narrowband PLC (NB-PLC) operating in the CENELEC-C band (125–140 kHz) taking into account realistic noise models. Our system is based on binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK) modulation.","PeriodicalId":190644,"journal":{"name":"2017 IEEE 9th Latin-American Conference on Communications (LATINCOM)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126580056","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 : 2017-11-01DOI: 10.1109/LATINCOM.2017.8240192
Atul Kumar, M. Magarini, S. Bregni
The shifting towards New Radio waveforms for future cellular networks will require a smooth transition from the existing 4G physical layer (PHY), which is based on the LongTerm Evolution-Advance (LTE-A) system. This will allow the service provider to develop less cost multi-standard devices that rely on the same master clock compatibility and with the same time-frequency grid representation of the LTE-A. The main characteristic of generalized frequency-division multiplexing (GFDM) modulation is low out-of-band (OOB) emission, accomplished by using flexible pulse shape filtering in the timedomain of individual subcarriers. In this paper, first we focus on the integration of GFDM in the time-frequency grid of the LTE-A system and then we analyze the impact of “Better than Nyquist” pulse shaping filters on OOB emission and symbol error rate. We consider different “Better than Nyquist” pulse shaping filters that were originally introduced in single-carrier modulation schemes to reduce the sensitivity to symbol timing error. By using the results available in the literature, the performance achieved by “Better than Nyquist” pulse shaping filters is compared to that achieved by conventional Nyquist ones. The concept of the wavelet, based on the Meyer auxiliary function, along with pulse shaping filter will be also addressed. The results are presented for 16-QAM in the case of transmission over AWGN, time-varying frequency flat, and static frequency selective fading channels. Monte Carlo simulations are shown in order to validate the accuracy of the analytical expressions.
未来蜂窝网络向新无线电波形式的转变将需要从现有的基于长期演进-先进(LTE-A)系统的4G物理层(PHY)平稳过渡。这将允许服务提供商开发成本更低的多标准设备，这些设备依赖于相同的主时钟兼容性和相同的LTE-A时频网格表示。广义频分复用(GFDM)调制的主要特性是低带外(OOB)发射，这是通过在单个子载波的时域中使用柔性脉冲形状滤波来实现的。本文首先研究了LTE-A系统时频网格中GFDM的集成，然后分析了Better than Nyquist脉冲整形滤波器对OOB发射和码元错误率的影响。我们考虑了最初在单载波调制方案中引入的不同的“优于奈奎斯特”脉冲整形滤波器，以降低对符号时序误差的灵敏度。通过使用文献中可用的结果，将“优于奈奎斯特”脉冲整形滤波器的性能与传统奈奎斯特脉冲整形滤波器的性能进行比较。基于Meyer辅助函数的小波的概念以及脉冲整形滤波器也将被讨论。给出了在AWGN、时变平坦频率和静态频率选择性衰落信道上传输16-QAM的结果。为了验证解析表达式的准确性，给出了蒙特卡罗模拟。
{"title":"Impact of “Better than Nyquist” pulse shaping in GFDM PHY with LTE-compatible frame structure","authors":"Atul Kumar, M. Magarini, S. Bregni","doi":"10.1109/LATINCOM.2017.8240192","DOIUrl":"https://doi.org/10.1109/LATINCOM.2017.8240192","url":null,"abstract":"The shifting towards New Radio waveforms for future cellular networks will require a smooth transition from the existing 4G physical layer (PHY), which is based on the LongTerm Evolution-Advance (LTE-A) system. This will allow the service provider to develop less cost multi-standard devices that rely on the same master clock compatibility and with the same time-frequency grid representation of the LTE-A. The main characteristic of generalized frequency-division multiplexing (GFDM) modulation is low out-of-band (OOB) emission, accomplished by using flexible pulse shape filtering in the timedomain of individual subcarriers. In this paper, first we focus on the integration of GFDM in the time-frequency grid of the LTE-A system and then we analyze the impact of “Better than Nyquist” pulse shaping filters on OOB emission and symbol error rate. We consider different “Better than Nyquist” pulse shaping filters that were originally introduced in single-carrier modulation schemes to reduce the sensitivity to symbol timing error. By using the results available in the literature, the performance achieved by “Better than Nyquist” pulse shaping filters is compared to that achieved by conventional Nyquist ones. The concept of the wavelet, based on the Meyer auxiliary function, along with pulse shaping filter will be also addressed. The results are presented for 16-QAM in the case of transmission over AWGN, time-varying frequency flat, and static frequency selective fading channels. Monte Carlo simulations are shown in order to validate the accuracy of the analytical expressions.","PeriodicalId":190644,"journal":{"name":"2017 IEEE 9th Latin-American Conference on Communications (LATINCOM)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125509666","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 : 2017-11-01DOI: 10.1109/LATINCOM.2017.8240157
Robhyson Denys R. da Silva, S. Motoyama
A WBANs (Wireless Body Area Networks) number dimensioning technique for cluster-type network structure is proposed in this paper. The WBANs, in this structure, are placed, together with the sink nodes, at the ends of the network. An access scheme is provided so that the sink nodes, which temporarily store the data packets of the WBANs, transmit these packets to the collector nodes. The collector nodes compose a cluster, and they cooperate with each other to send the data packets up to the coordinator node which in its turn has access to the hospital directly or through the Internet. All the transmission links used in this structure are wireless of relatively low capacities. In addition, since the data are medicals, there is a need for such data to reach the hospital as quickly as possible. For the calculation of number of WBANs, the proposed dimensioning technique uses, as main criterion, the limitation of total delay in the network. The results show that link capacities and total network delay are essential for dimensioning the number of WBANs.
{"title":"Dimensioning of WBANs number for cluster-type network structure","authors":"Robhyson Denys R. da Silva, S. Motoyama","doi":"10.1109/LATINCOM.2017.8240157","DOIUrl":"https://doi.org/10.1109/LATINCOM.2017.8240157","url":null,"abstract":"A WBANs (Wireless Body Area Networks) number dimensioning technique for cluster-type network structure is proposed in this paper. The WBANs, in this structure, are placed, together with the sink nodes, at the ends of the network. An access scheme is provided so that the sink nodes, which temporarily store the data packets of the WBANs, transmit these packets to the collector nodes. The collector nodes compose a cluster, and they cooperate with each other to send the data packets up to the coordinator node which in its turn has access to the hospital directly or through the Internet. All the transmission links used in this structure are wireless of relatively low capacities. In addition, since the data are medicals, there is a need for such data to reach the hospital as quickly as possible. For the calculation of number of WBANs, the proposed dimensioning technique uses, as main criterion, the limitation of total delay in the network. The results show that link capacities and total network delay are essential for dimensioning the number of WBANs.","PeriodicalId":190644,"journal":{"name":"2017 IEEE 9th Latin-American Conference on Communications (LATINCOM)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126176553","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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