A Summary of IEEE Standard. IEEE defines the communications mechanism for RuBee tags. RuBee tags have very low power consumption (a. Introduction • It’s a wireless data communication protocol based on IEEE • RuBee is proposed for high security applications and use in. PDF | This work presents an investigation on the use of the IEEE (RuBee) protocol in order to communicate with buried assets. This is an important.
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Although very resistant to interference, metal, water and obstacles, it is very limited in range, usually only suitable for short-range networks under 70 feet. This standard is aimed at the conception of wireless network of sensors and actuators in industrial and military environments.
RuBee tags emit virtually no RF and do not produce any Compromising Emanations, as a result are used in high security facilities. RuBee tags are safe and in use near and on high explosive facilities. Other concurrent standards also exist: RuBee stands in contrast to the well-known network certification ZigBeea related but completely different networking standard.
The Controller initiates a command request and the Responder detects the request, processes some functions like measuring pressure, temperature or activating a relay, before sending a Response packet back to the Controller.
The maximum power of emission recommended is 10 micro-Watts. This power limits the area of the network to a piconetbetween 0. Inductive coupling power falls cubically with the distance between the Controller and Responder. The Controller must support both modulations, although the Responder may only support one.
On top of the modulation, the IEEE This encoding method combined with BPSK is insensitive to a polarity reversal and has a good signal-to-noise ratio. The protocol is simple: Two types of PDUs are available for use in the protocol: Each support an application protocol that the specific implementation must define. A frame check sequence is responsible for error checking, which, due to the system’s simplicity, must be done on the application layer. The protocol uses heuristics – measures that generally work but do not absolutely guarantee their reception or accuracy – in order to be most efficient.
Unlike the Carrier Sense Multiple Access CSMA standard there is no anti-collision mechanism; multiple signals are unable to be distinguished by the network if the Controllers and Responders are not completely synchronized.
The Controller is considered permanently “Awake” and to have a power supply provided by a permanent source. The Responder is made to work on battery and alternate between “Listening” and “Sleeping” states. Thus, the Responder can detect the communicating Controller and stay listening.
If there are many Responders and if the Controller uses only the one-to-one Request PDU, the Responder will stay listening for all commands sent and received on the network, and therefore may stay permanently awake. The use of responder groups, multicast or broadcasthelp to better manage battery life for the Responders. An optimization for the cost and sleeping period of the Request PDUs must be done on the application layer.
A nice feature proposed in the standard is a frequency available to broadcast energy and supply the Responders. This frequency is As the medium in an inductive signal, the signal diminishes cubically, so the Responders must sleep quite a long time in order to store enough energy to listen and respond to the Controller requests.
It is often desirable for them to charge for periods of time before being used again. Use of a higher wattage is not allowed in Europe. BMC encoding on BPSK modulation allows synchronizing the listening of the carrier on a specific Responder or Controller signal, rejecting all other signals as noise. If a network is composed of many Controllers and a large number of Responders, the Controllers’ requests are synchronized as well as Responders’ responses the “Clip” mechanism.
In the traditional ” volume multiplexing ” concept, however, the Controllers would be placed nearby their Responders and answer only to the nearest Controller.
This “Clip” Controller signal is much better that others at greater distances and filters out more noise. Department of Energy DoE. Dipole antenna — In radio ieef telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna. A dipole antenna consists of two identical conductive elements such as metal wires or rods, which are usually bilaterally symmetrical.
The driving current from the transmitter is applied, or for receiving antennas the output signal to the receiver is taken, between the two halves of the antenna, each side of the feedline to the transmitter or receiver is connected to one of the conductors. This contrasts with an antenna, which consists of a single rod or conductor with one side of the feedline connected to it. A common example of a dipole is the rabbit ears television antenna found on broadcast television sets and this is the simplest type of antenna from a theoretical point of view.
Dipoles are resonant antennas, meaning that the serve as resonators, with standing waves of radio current flowing back. So the length of the elements is determined by the wavelength of the radio waves used. The radiation ieeee of a dipole is omnidirectional, it radiates equal power in all azimuthal directions perpendicular to the axis of the antenna. For a half-wave dipole the radiation is maximum,2. Several different variations of the dipole are also used, such as the dipole, short dipole, cage dipole, bow-tie.
The dipole was the earliest type of antenna, it was invented by German physicist Heinrich Hertz iee in his investigations of radio waves. The feedpoint impedance of an antenna is very sensitive to its electrical length. Therefore, a dipole will generally only perform optimally over a narrow bandwidth.
The real and imaginary components 11902.1 impedance, as a function of electrical length, are shown in the accompanying graph. The detailed calculation of these numbers are described below, note that the value of the reactance is highly dependent on the diameter of the conductors, oeee plot is for conductors with a diameter of.
Dipoles that are smaller than the wavelength of the signal are called short dipoles. These have a low radiation resistance making them inefficient antennas. Broadcasting — Broadcasting began with AM radio, which came into popular use around with the spread of vacuum tube radio transmitters and receivers. Before this, all forms of communication were one-to-one, with the message intended for a single recipient. Over the air broadcasting is usually associated with radio and television, the receiving parties may include the general public or a relatively small subset, the point is that anyone with the appropriate receiving technology and equipment can receive the signal.
The field of broadcasting includes both government-managed services such as radio, community radio and public television, and private commercial radio. Code of Federal Regulations, title 47, part 97 defines broadcasting as transmissions intended for reception by the general public, private or two-way telecommunications transmissions do not qualify under this definition.
RuBee Approved as New IEEE Standard | Sensors Magazine
Iee example, amateur and citizens band radio operators are not allowed to broadcast, as defined, transmitting and broadcasting are not the same. Transmissions using a wire or cable, like television, are also considered broadcasts. In the s, transmissions of television and radio programs via streaming digital technology have increasingly been referred to as broadcasting as well, the earliest broadcasting consisted iwee sending telegraph signals over the airwaves, using Morse code, a system developed in the s by Samuel F.
Morse, physicist Joseph Henry and Alfred Vail and they developed an electrical telegraph system which sent pulses of electric iere along wires which controlled an electromagnet that was located at the receiving end of the telegraph system.
A code was needed to 19002.1 natural language using only these pulses, Morse therefore developed the forerunner to modern International Morse code. Audio broadcasting began experimentally in the first decade of the 20th century, by the early s radio broadcasting became a household medium, at first on the AM band and later on FM.
Television broadcasting started experimentally in the s and became widespread after World War II, satellite broadcasting was initiated in the s and moved into general industry usage in the s, with DBS emerging in the s. Originally all broadcasting was composed of signals using analog transmission techniques but in the s. 1902.1 general usage, broadcasting most frequently refers to the transmission of information, Analog audio vs. HD Radio Analog television vs. This is the equivalent of 55 newspapers per person per day in Telephone broadcasting also grew idee include telephone services for news and entertainment programming which were introduced in the s.
United States Department of Defense — The Department is the largest employer in the world, with nearly 1. Adding to its employees are overNational Guardsmen and Reservists from the four services and it is headquartered at the Pentagon in Arlington, Virginia, just outside of Washington, D. The Department of Defense is headed by the Secretary of Defense, Military operations are managed by nine regional or functional Unified Combatant Commands.
The Department of Defense also operates several joint services schools, including the National Defense University, the history of the defense of the United States started with the Continental Congress eiee The Preamble of the United States Constitution gave the authority to federal government, to defend leee citizens and this first Congress had a huge agenda, that of creating legislation to build a government for the ages.
Legislation to create a military defense force stagnated, two separate times, President George Washington went to Congress to remind them of their duty to establish a military.
In a special message to Congress on 19 Decemberthe President cited both wasteful 1920.1 spending and inter-departmental conflicts, deliberations in Congress went on for months focusing heavily on the role of the military in society and the threat of granting too much military power to the executive. The act placed the National Military Establishment under the control of a single Secretary of Defense, the National Military Establishment formally began operations on 18 September, the day after the Senate confirmed James V.
Forrestal as the first Secretary of Defense.
IEEE – WikiVisually
The National Military Establishment was renamed the Department of Defense on 10 Augustunder the Department of Defense Reorganization Act ofchannels of authority within the department were streamlined, while still maintaining the authority of the Military Departments. Also provided in this legislation was a centralized authority, the Advanced Research Projects Agency.
The Act moved decision-making authority from the Military Departments to the Joint Chiefs of Staff and it also strengthened the command channel of the military over U. Written and promoted by the Eisenhower administration, it was signed into law 6 Augustbecause the Constitution vests all military authority in Congress and the President, the statutory authority of the Secretary of Defense is derived from their constitutional authorities.
Department of Defense Directive The latest version, signed by former Secretary of Defense Robert Gates in Decemberis the first major re-write sincethe Office of the Secretary of Defense is the Secretary and Deputy Secretarys civilian staff. Government departments and agencies, foreign governments, and international organizations, OSD also performs oversight and management of the Defense Agencies and Department of Defense Field Activities.
OSD also supervises the following Defense Agencies, Several defense agencies are members of the United States Intelligence Community and these are national-level intelligence services that operate under the jurisdiction of the Department of Defense but simultaneously fall under the authorities of the Director of National Intelligence.
Newer standards have largely replaced IEEE for computer use, in the late s, Hewlett-Packard manufactured various automated test and measurement instruments, such as digital multimeters and logic analyzers.
They developed the HP Interface Bus to enable easier interconnection between instruments and controllers, the bus was relatively easy to implement using the technology at the time, using a simple parallel bus and several individual control lines.
It became known as the General Purpose Interface Bus, and became a de facto standard for automated, as GPIB became popular, it was formalized by various standards ieee.
Commands to control the same class of instrument, e. This was incorporated into the standard inover HPs objections. The bus employs sixteen iewe lines — eight used for data transfer. Every device on the bus has a unique 5-bit primary address, the ieeee allows up to 15 devices to share a single physical bus of up to 20 meters total cable length.
It was originally developed in the s by Centronics, and was known as the Centronics port.
In the s, Centronics developed the now-familiar printer parallel port that became a de facto standard. Centronics had introduced the first successful low-cost seven-wire print head, which used a series of solenoids to pull the metal pins to strike a ribbon.
A dot matrix print head consists of a series of pins arranged in a vertical row. Each pin is attached to some sort of actuator, a solenoid in the case of Centronics, which can pull the pin forward to strike a ribbon and the paper.
The entire print head is moved horizontally in order to print a line of text, character sets on early printers normally used 7 by 5 pixels to produce column text.