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Time Slotted Channel Hopping
Time Slotted Channel Hopping or Time Synchronized Channel Hopping (TSCH) is a channel access method for shared-medium networks. TSCH is used by Low-Power devices to communicate using a wireless link. It is designed for low-power and lossy networks (LLNs) and aims at providing a reliable Media access control layer. TSCH can be seen as a combination of Time division multiple access and Frequency-division multiple access mechanisms as it uses diversity in time and frequency to provide reliability to the upper network layers. The TSCH mode was introduced in 2012 as an amendment (IEEE 802.15.4e) to the Medium Access Control (MAC) portion of the IEEE 802.15.4 standard. The amendment was rolled into the IEEE 802.15.4 in 2015. Description Wireless communications are often referred as unreliable due to the unpredictability of the wireless medium. While wireless communications bring many advantages (e.g no wires maintenance, costs reduction ...), the lack of reliability slows down the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TSMP
TSMP, an acronym for Time Synchronized Mesh Protocol, was developed by Dust Networks as a communications protocol for self-organizing networks of wireless devices called ''motes''. TSMP devices stay synchronized to each other and communicate in time-slots, similar to other TDM (time-division multiplexing) systems. Such deterministic communication allows the devices to stay extremely low power, as the radios only turn on for the periods of scheduled communication. The protocol is designed to operate very reliably in a noisy environment. It uses channel hopping to avoid interference -- the packets between TSMP devices get sent on different radio channels depending on time of transmission. TSMP distinguishes itself from other time-slotted mesh-based protocols, in that time-slot timing is maintained continuously and enables a network to duty-cycle on a transmitter-receiver pair-wise basis, as opposed to putting the entire network to sleep for extended periods of time (as is done in a beac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RIOT (operating System)
RIOT is a small operating system for networked, memory-constrained systems with a focus on low-power wireless Internet of things (IoT) devices. It is open-source software, released under the GNU Lesser General Public License (LGPL). Background It was initially developed by Free University of Berlin (FU Berlin), French Institute for Research in Computer Science and Automation (INRIA) and the Hamburg University of Applied Sciences (HAW Hamburg). RIOT's kernel is mostly inherited from FireKernel, which was originally developed for sensor networks. Technical aspects RIOT is based on a microkernel architecture. In contrast to other operating systems with similarly low memory use (such as TinyOS or Contiki), RIOT allows application software programming with the programming languages C and C++, and Rust, also by an experimental application programming interface (API). It has full multithreading and real-time abilities. Secure Sockets Layer (SSL) and successor Transport Layer Security ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WirelessHART
WirelessHART within telecommunications and computing, is a wireless sensor networking technology. It is based on the Highway Addressable Remote Transducer Protocol (HART). Developed as a multi-vendor, interoperable wireless standard, WirelessHART was defined for the requirements of process field device networks. Technical description The protocol utilizes a time synchronized, self-organizing, and self-healing mesh architecture. The protocol supports operation in the 2.4 GHz ISM band using IEEE 802.15.4 standard radios. The underlying wireless technology is based on the work of Dust Networks' TSMP technology. History The standard was initiated in early 2004 and developed by 37 HART Communications Foundation (HCF) companies that - amongst others - included ABB, Emerson, Endress+Hauser, Pepperl+Fuchs, Siemens, Freescale Semiconductor, Software Technologies Group (which developed the initial WirelessHART WiTECK stack), and AirSprite Technologies which went on to form WiTECK, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emerson Electric
Emerson Electric Co. is an American multinational corporation headquartered in Ferguson, Missouri. The ''Fortune'' 500 company manufactures products and provides engineering services for industrial, commercial, and consumer markets."David Farr" Emerson has approximately 86,700 employees and 170 manufacturing locations. History Emerson was established in 1890 in , as ''Emerson Electric Manufacturing Co.'' by Union veteran |
Linear Technology
Linear Technology Corporation was an American semiconductor company that designed, manufactured and marketed high performance analog integrated circuits. Applications for the company's products included telecommunications, cellular telephones, networking products, notebook and desktop computers, video/multimedia, industrial instrumentation, automotive electronics, factory automation, process control, military and space systems. The company was founded in 1981 by Robert H. Swanson, Jr. and Robert C. Dobkin. In July 2016, Analog Devices agreed to buy Linear Technology for 14.8 billion dollars. This acquisition was finalized on March 10, 2017. The Linear name survives as the "Power by Linear" brand that is used to market the combined power management portfolios of Linear Technology and Analog Devices. Products As of August 2010, the company made over 7500 products, which they organized into seven product categories: data conversion (analog to digital converters, digital to anal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wireless Sensor Network
Wireless sensor networks (WSNs) refer to networks of spatially dispersed and dedicated sensors that monitor and record the physical conditions of the environment and forward the collected data to a central location. WSNs can measure environmental conditions such as temperature, sound, pollution levels, humidity and wind. These are similar to wireless ad hoc networks in the sense that they rely on wireless connectivity and spontaneous formation of networks so that sensor data can be transported wirelessly. WSNs monitor physical conditions, such as temperature, sound, and pressure. Modern networks are bi-directional, both collecting data and enabling control of sensor activity. The development of these networks was motivated by military applications such as battlefield surveillance. Such networks are used in industrial and consumer applications, such as industrial process monitoring and control and machine health monitoring. A WSN is built of "nodes" – from a few to hundreds or th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contiki
Contiki is an operating system for networked, memory-constrained systems with a focus on low-power wireless Internet of Things (IoT) devices. Extant uses for Contiki include systems for street lighting, sound monitoring for smart cities, radiation monitoring, and alarms.. It is open-source software released under the BSD-3-Clause license. Contiki was created by Adam Dunkels in 2002 and has been further developed by a worldwide team of developers from Texas Instruments, Atmel, Cisco, ENEA, ETH Zurich, Redwire, RWTH Aachen University, Oxford University, SAP, Sensinode, Swedish Institute of Computer Science, ST Microelectronics, Zolertia, and many others. Contiki gained popularity because of its built in TCP/IP stack and lightweight preemptive scheduling over event-driven kernel which is a very motivating feature for IoT. The name ''Contiki'' comes from Thor Heyerdahl's famous Kon-Tiki raft. Contiki provides multitasking and a built-in Internet Protocol Suite (TCP/IP stack), yet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEEE 802
IEEE 802 is a family of Institute of Electrical and Electronics Engineers (IEEE) standards for local area networks (LAN), personal area network (PAN), and metropolitan area networks (MAN). The IEEE 802 LAN/MAN Standards Committee (LMSC) maintains these standards. The IEEE 802 family of standards has had twenty-four members, numbered 802.1 through 802.24, with a working group of the LMSC devoted to each. However, not all of these working groups are currently active. The IEEE 802 standards are restricted to computer networks carrying variable-size packets, unlike cell relay networks, for example, in which data is transmitted in short, uniformly sized units called cells. Isochronous signal networks, in which data is transmitted as a steady stream of octets, or groups of octets, at regular time intervals, are also outside the scope of the IEEE 802 standards. The number 802 has no significance: it was simply the next number in the sequence that the IEEE used for standards projects. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Channel Access Method
In telecommunications and computer networks, a channel access method or multiple access method allows more than two terminals connected to the same transmission medium to transmit over it and to share its capacity. Examples of shared physical media are wireless networks, bus networks, ring networks and point-to-point links operating in half-duplex mode. A channel access method is based on multiplexing, that allows several data streams or signals to share the same communication channel or transmission medium. In this context, multiplexing is provided by the physical layer. A channel access method may also be a part of the multiple access protocol and control mechanism, also known as medium access control (MAC). Medium access control deals with issues such as addressing, assigning multiplex channels to different users and avoiding collisions. Media access control is a sub-layer in the data link layer of the OSI model and a component of the link layer of the TCP/IP model. Fundame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multipath Propagation
In radio communication, multipath is the propagation phenomenon that results in radio signals reaching the receiving antenna by two or more paths. Causes of multipath include atmospheric ducting, ionospheric reflection and refraction, and reflection from water bodies and terrestrial objects such as mountains and buildings. When the same signal is received over more than one path, it can create interference and phase shifting of the signal. Destructive interference causes fading; this may cause a radio signal to become too weak in certain areas to be received adequately. For this reason, this effect is also known as multipath interference or multipath distortion. Where the magnitudes of the signals arriving by the various paths have a distribution known as the Rayleigh distribution, this is known as Rayleigh fading. Where one component (often, but not necessarily, a line of sight component) dominates, a Rician distribution provides a more accurate model, and this is known as Ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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