The IEEE 802.15.4a standard provides a framework for low-data-rate communication systems,typically sensor networks.In this paper,we established a realistic environment for the time delay characteristic of industrial n...The IEEE 802.15.4a standard provides a framework for low-data-rate communication systems,typically sensor networks.In this paper,we established a realistic environment for the time delay characteristic of industrial network based on IEEE 802.15.4a.Several sets of practical experiments are conducted to study its various features,including the effects of 1） numeral wireless nodes,2） numeral data packets,3） data transmissions with different upper-layer protocols,4） physical distance between nodes,and 5） adding and reducing the number of the wireless nodes.The results show that IEEE 802.15.4a is suitable for some industrial applications that have more relaxed throughput requirements and time-delay.Some issues that could degrade the network performance are also discussed.展开更多
As location-based techniques and applications have become ubiquitous in emerging wireless networks, the verification of location information has become more important. In recent years, there has been an explosion of a...As location-based techniques and applications have become ubiquitous in emerging wireless networks, the verification of location information has become more important. In recent years, there has been an explosion of activity related to lo- cation-verification techniques in wireless networks. In particular, there has been a specific focus on intelligent transport systems because of the mission-critical nature of vehicle location verification. In this paper, we review recent research on wireless location verification related to vehicular networks. We focus on location verification systems that rely on for- mal mathematical classification frameworks and show how many systems are either partially or fully encompassed by such frameworks.展开更多
This paper introduces an instrument and method for lamp life test. The design of the instrument is divided into three steps: the overall design scheme, hardware circuit design and host machine programming. The instrum...This paper introduces an instrument and method for lamp life test. The design of the instrument is divided into three steps: the overall design scheme, hardware circuit design and host machine programming. The instrument contains luminance and temperature sensors which can measure luminance of the lamp lighting and environment temperature in the instrument body. Then, the measure data can be transmitted to PC via the wireless transceiver modules for real-time monitoring. The luminance degradation curve based on the measure data is used to reckon the life of the lamp. In the end, the method for processing measurement data is given.展开更多
The wireless communication system's performance is greatly constrained by the wireless channel characteristics,especially in some specific environment.Therefore,signal transmission will be greatly impacted even if...The wireless communication system's performance is greatly constrained by the wireless channel characteristics,especially in some specific environment.Therefore,signal transmission will be greatly impacted even if not in a complicated topography.Testing results show that it is hardly to characterize the radio propagation properties for the antenna installed on the ground.In order to ensure a successful communication,the radio frequency(RF)wireless signal intensity monitor system was designed.We can get the wireless link transmission loss through measuring signal strength from received node.The test shows that the near-ground wireless signal propagation characteristics still can be characterized by the log distance propagation loss model.These results will conduce to studying the transmission characteristic of Near-Earth wireless signals and will predict the coverage of the earth's surface wireless sensor network.展开更多
Internet of Things (IOT) is a conceptual vision to connect things in order to create a ubiquitous computing world. In order to create such an ever-present network, a simple, reliable, and cost-effective technology is ...Internet of Things (IOT) is a conceptual vision to connect things in order to create a ubiquitous computing world. In order to create such an ever-present network, a simple, reliable, and cost-effective technology is crucial. Wireless sensor network (WSN) is an important wireless technology that has wide variety of applications and provides unlimited future potentials for IOT. Since WSNs in IOT will be used in varying and challenging applications and environments, reliability and reliability testing of WSN hardware becomes extremely important. In accelerated reliability testing, test stresses are increased to cut down the time required to obtain a weakening effect similar to one resulting from normal service conditions in the field. This paper introduces three common difficulties that engineers may experience in qualitative accelerated testing of WSN devices: 1. Challenges in use of standard accelerated tests, 2. Challenges in component-level testing, and 3. Challenges in testing of prototypes. The paper will also introduce examples from real life reliability research and accelerated tests to clarify the presented challenges.展开更多
基金supported by National High Technology Research and Development Program of China (863 Program)(No. 2007AA04Z174,No. 2006AA04030405)National Natural Science Foundation of China (No. 61074032,No. 60834002)
文摘The IEEE 802.15.4a standard provides a framework for low-data-rate communication systems,typically sensor networks.In this paper,we established a realistic environment for the time delay characteristic of industrial network based on IEEE 802.15.4a.Several sets of practical experiments are conducted to study its various features,including the effects of 1） numeral wireless nodes,2） numeral data packets,3） data transmissions with different upper-layer protocols,4） physical distance between nodes,and 5） adding and reducing the number of the wireless nodes.The results show that IEEE 802.15.4a is suitable for some industrial applications that have more relaxed throughput requirements and time-delay.Some issues that could degrade the network performance are also discussed.
基金supported by the University of New South Wales and the Australian Research Council under grant No.DP120102607
文摘As location-based techniques and applications have become ubiquitous in emerging wireless networks, the verification of location information has become more important. In recent years, there has been an explosion of activity related to lo- cation-verification techniques in wireless networks. In particular, there has been a specific focus on intelligent transport systems because of the mission-critical nature of vehicle location verification. In this paper, we review recent research on wireless location verification related to vehicular networks. We focus on location verification systems that rely on for- mal mathematical classification frameworks and show how many systems are either partially or fully encompassed by such frameworks.
基金Sponsored by the Higher School Scientific Research Project Plan of Department of Education of Liaoning Province of China (Grant No. 2009A085)
文摘This paper introduces an instrument and method for lamp life test. The design of the instrument is divided into three steps: the overall design scheme, hardware circuit design and host machine programming. The instrument contains luminance and temperature sensors which can measure luminance of the lamp lighting and environment temperature in the instrument body. Then, the measure data can be transmitted to PC via the wireless transceiver modules for real-time monitoring. The luminance degradation curve based on the measure data is used to reckon the life of the lamp. In the end, the method for processing measurement data is given.
文摘The wireless communication system's performance is greatly constrained by the wireless channel characteristics,especially in some specific environment.Therefore,signal transmission will be greatly impacted even if not in a complicated topography.Testing results show that it is hardly to characterize the radio propagation properties for the antenna installed on the ground.In order to ensure a successful communication,the radio frequency(RF)wireless signal intensity monitor system was designed.We can get the wireless link transmission loss through measuring signal strength from received node.The test shows that the near-ground wireless signal propagation characteristics still can be characterized by the log distance propagation loss model.These results will conduce to studying the transmission characteristic of Near-Earth wireless signals and will predict the coverage of the earth's surface wireless sensor network.
文摘Internet of Things (IOT) is a conceptual vision to connect things in order to create a ubiquitous computing world. In order to create such an ever-present network, a simple, reliable, and cost-effective technology is crucial. Wireless sensor network (WSN) is an important wireless technology that has wide variety of applications and provides unlimited future potentials for IOT. Since WSNs in IOT will be used in varying and challenging applications and environments, reliability and reliability testing of WSN hardware becomes extremely important. In accelerated reliability testing, test stresses are increased to cut down the time required to obtain a weakening effect similar to one resulting from normal service conditions in the field. This paper introduces three common difficulties that engineers may experience in qualitative accelerated testing of WSN devices: 1. Challenges in use of standard accelerated tests, 2. Challenges in component-level testing, and 3. Challenges in testing of prototypes. The paper will also introduce examples from real life reliability research and accelerated tests to clarify the presented challenges.
