The huge amount of electrical power of many countries is consumed in lighting the streets. However, vehicles pass with very low rate in specific periods of time and parts of the streets are not occupied by vehicles ov...The huge amount of electrical power of many countries is consumed in lighting the streets. However, vehicles pass with very low rate in specific periods of time and parts of the streets are not occupied by vehicles over time. In this paper, we propose a system that automatically switches off the light for the parts of the streets having no vehicles and turns on the light for these parts once there are some vehicles that are going to come. Logically, this system may save a large amount of the electrical power. In addition, it may increase the lifetime of the lamps and reduce the pollutions. This system automatically controls and monitors the light of the streets. It can light only the parts that have vehicles and help on the maintenance of the lighting equipments. Vehicular Ad-Hoc Networks (VANET) make it possible to propose such system. VANET enables the possibility to know the presence of vehicles, their locations, their directions and their speeds in real time. These quantities are what are needed to develop this system. An advantage of using VANET is that there is no need to use specific network and equipments to design the system, but VANET infrastructure will be used. This decreases the cost and speed up the deployment of such system. This paper focuses on the proposal of different possible architectures of this system. Results show that the saved energy may reach up to 65% and an increase of the lifetime of the lamps of 53%.展开更多
针对室外无线信道视距(line of sight,LOS)/非视距(non-line of sight,NLOS)传输环境下的车到车(vehicular-to-vehicular,V2V)通信系统,本文提出了一种基于标准街道散射的统计信道模型,其移动发射机(mobile transmitter,MT)与移动接收机...针对室外无线信道视距(line of sight,LOS)/非视距(non-line of sight,NLOS)传输环境下的车到车(vehicular-to-vehicular,V2V)通信系统,本文提出了一种基于标准街道散射的统计信道模型,其移动发射机(mobile transmitter,MT)与移动接收机(mobile receiver,MR)处于运动状态,街道两旁分布的散射体固定.由几何模型出发又引入了一种随机的参考信道模型,其散射体有无穷多个,均以平行于街道两侧的散射条纹形式均匀分布在三维(three dimensional,3D)空间的一个二维(two dimensional,2D)矩形内部.在室外街道通信环境下,模型推导了散射信道中发射角(angle of departure,AOD)以及到达角(angle of arrival,AOA)的概率密度函数(probability density functions,PDFs)解析式;研究了多普勒功率谱密度(power spectral density,PSD)及其时间自相关函数(autocorrelation function,ACF);分析了模型多普勒参数以及街道散射体等因素对V2V通信系统性能的影响.与城市、农村的测量信道对比分析,表明本模型仿真的统计特性符合理论与实际,拓宽了室外V2V无线通信信道建模的研究.为评估室外V2V通信系统的传输特性、仿真无线通信系统提供了有力的研究工具.展开更多
车载网VANETs(Vehicular Ad hoc Networks)在道路安全、车流量管理和娱乐应用具有广阔的前景,而这些应用依赖数据有效的传输。为此,VANETs的数据传输技术成为研究的焦点。然而,VANETs的拓扑动态变化、车辆快速移动加速了车间通信链路的...车载网VANETs(Vehicular Ad hoc Networks)在道路安全、车流量管理和娱乐应用具有广阔的前景,而这些应用依赖数据有效的传输。为此,VANETs的数据传输技术成为研究的焦点。然而,VANETs的拓扑动态变化、车辆快速移动加速了车间通信链路的断裂,降低了链路的可靠性,为数据有效传输提出了挑战。据此,分析了VANETs的多跳通信连接特性。通过研究端到端中断概率,提出多跳连接的分析模型。通过模型,可得出在一定的平均端到端中断概率所需的最小发射功率以及最大传输跳数。通过仿真,验证理论模型的正确性。仿真进一步表明,通过合适的功率控制算法有利于改善数据传输路径。展开更多
文摘The huge amount of electrical power of many countries is consumed in lighting the streets. However, vehicles pass with very low rate in specific periods of time and parts of the streets are not occupied by vehicles over time. In this paper, we propose a system that automatically switches off the light for the parts of the streets having no vehicles and turns on the light for these parts once there are some vehicles that are going to come. Logically, this system may save a large amount of the electrical power. In addition, it may increase the lifetime of the lamps and reduce the pollutions. This system automatically controls and monitors the light of the streets. It can light only the parts that have vehicles and help on the maintenance of the lighting equipments. Vehicular Ad-Hoc Networks (VANET) make it possible to propose such system. VANET enables the possibility to know the presence of vehicles, their locations, their directions and their speeds in real time. These quantities are what are needed to develop this system. An advantage of using VANET is that there is no need to use specific network and equipments to design the system, but VANET infrastructure will be used. This decreases the cost and speed up the deployment of such system. This paper focuses on the proposal of different possible architectures of this system. Results show that the saved energy may reach up to 65% and an increase of the lifetime of the lamps of 53%.
文摘针对室外无线信道视距(line of sight,LOS)/非视距(non-line of sight,NLOS)传输环境下的车到车(vehicular-to-vehicular,V2V)通信系统,本文提出了一种基于标准街道散射的统计信道模型,其移动发射机(mobile transmitter,MT)与移动接收机(mobile receiver,MR)处于运动状态,街道两旁分布的散射体固定.由几何模型出发又引入了一种随机的参考信道模型,其散射体有无穷多个,均以平行于街道两侧的散射条纹形式均匀分布在三维(three dimensional,3D)空间的一个二维(two dimensional,2D)矩形内部.在室外街道通信环境下,模型推导了散射信道中发射角(angle of departure,AOD)以及到达角(angle of arrival,AOA)的概率密度函数(probability density functions,PDFs)解析式;研究了多普勒功率谱密度(power spectral density,PSD)及其时间自相关函数(autocorrelation function,ACF);分析了模型多普勒参数以及街道散射体等因素对V2V通信系统性能的影响.与城市、农村的测量信道对比分析,表明本模型仿真的统计特性符合理论与实际,拓宽了室外V2V无线通信信道建模的研究.为评估室外V2V通信系统的传输特性、仿真无线通信系统提供了有力的研究工具.
文摘车载网VANETs(Vehicular Ad hoc Networks)在道路安全、车流量管理和娱乐应用具有广阔的前景,而这些应用依赖数据有效的传输。为此,VANETs的数据传输技术成为研究的焦点。然而,VANETs的拓扑动态变化、车辆快速移动加速了车间通信链路的断裂,降低了链路的可靠性,为数据有效传输提出了挑战。据此,分析了VANETs的多跳通信连接特性。通过研究端到端中断概率,提出多跳连接的分析模型。通过模型,可得出在一定的平均端到端中断概率所需的最小发射功率以及最大传输跳数。通过仿真,验证理论模型的正确性。仿真进一步表明,通过合适的功率控制算法有利于改善数据传输路径。
