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Improving Wireless Signal Strength. Wireless Pocket Usb Driver.

Improving Wireless Signal Strength

improving wireless signal strength

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As a child, we may remember hiding behind a wall, be it from parents, siblings, friends or teachers. However, these days it has a flip side pertaining to people involved in malicious activities.
Engineers of the University of Utah have revealed that wireless network of radio transmitters can track humans moving behind solid walls. This system would lend a great help to fire fighters and police to nab intruders and also to rescue hostages, fire victims, and more. The researchers- Patwari, an assistant professor and Wilson, a doctoral student are in the University’s Department of Electrical and Computer Engineering.
“By showing the locations of people within a building during hostage situations, fires or other emergencies, radio tomography can help law enforcement and emergency responders to know where they should focus their attention,” Joey Wilson and Neal Patwari wrote in one of two new studies of the method.
The method proposed by the researchers use radio tomographic imaging (RTI). This enables viewing, locating as well as tracking people/objects that are surrounded by radio transceivers which send and receive signals. All this negates the need for radio-transmitting ID tags. A study outlining the method and testing it in an indoor atrium and a grassy area with trees will soon be published in a journal of the Institute of Electrical and Electronics Engineers.
The study included a wireless network of 28 inexpensive radio transceivers (nodes) placed around a square portion of the atrium alongside a similar portion of the lawn. The square in the atrium was about 14 feet long with eight nodes spaced 2 feet apart. While the square on the lawn with 21 feet side features nodes placed 3 feet apart. The transceivers were placed on 4-foot-tall stands. By measuring the radio signals between all nodes as a person walked in each area, the processed radio signal strength data were displayed on a computer screen forming a bird’s-eye-view, blob-like image of the person.
Patwari says the system still needs improvements, “but the plan is that when there is a hostage situation, for example, or some kind of event that makes it dangerous for police or firefighters to enter a building, then instead of entering the building first, they would throw dozens of these radios around the building and immediately they would be able to see a computer image showing where people are moving inside the building.”
Another study offered an improved method which allowed tracking through walls. The study showed that variations in radio signal strength within a wireless network of 34 nodes enables tracking of moving people behind brick walls. The wireless system wasn’t a Wi-Fi network rather researchers used the Zigbee network.
Though it will be unable to distinguish between the hostages and bad guys, but the location of people will be given.
“Does a certain marketing display get people to stop or does it not?” Wilson asks. “I’m thinking of retail stores or grocery stores. They spend a lot of money to determine, ‘Where should we put the cereal, where should we put the milk, where should we put the bread?’ If I can offer that information using radio tomographic imaging, it’s a big deal.”
Measuring the radio signal strengths from all the transceivers (with and without a moving object) in their indoor, outdoor and through-the wall experiments, Patwari and Wilson developed math formulas to convert weaker or attenuated signals while an object moves into signals into a blob-like, bird’s-eye-view image. The Radio tomographic imaging (RTI) is less expensive compared to radars and measures shadows in radio waves rather than echoes or reflections calculated in radar.
The radio frequency signals can travel through walls, trees and smoke and other obstacles. On the other hand, optical and infrared imaging systems do not possess this ability. The researchers talk about various benefits that the system will offer in marketing as well as to elderly people. Keeping in mind the past incidents, it may prove to be a great technology to safeguard against hazardous elements.

Modular Prosthetic-limb System

Modular Prosthetic-limb System

Modular prosthetic-limb system, prototype. Stuart D. Harshbarger (American, b. 1964), Johns Hopkins University Applied Physics Laboratory and Orthocare Innovations, Thomas Van Doren (American, b. 1966), HDT Engineering Services, Richard Weir (American, b. 1960), Rehabilitation Institute of Chicago, and John D. Bigelow (American, b. 1957), Johns Hopkins University Applied Physics Laboratory; additional designers: Robert Armiger, James Beaty, Michael Bridges, James Burck, Michelle Chen, Steven Clark, Chad Dize, Harry Eaton, Eric Faulring, Michael Goldfarb, Ezra Johnson, Matthew Kozlowski, Niranjan Kumar, Lonnie Love, Courtney Leigh Moran, Tom Moyer, Aseem Raval, Julio Santos-Munne, Grace Tran, Matthew Van Doren, R. Jacob Vogelstein, Douglas Wenstrand, Michael Zeher. Manufactured by Johns Hopkins University Applied Physics Laboratory, HDT Engineering Services, and Orthocare Innovations. United States, 2009–present. Aluminum alloys, plastic, carbon-fiber composites, machined metals, electronic components. Courtesy of designers

The design and function of prosthetic arms have lagged behind lower-limb prostheses, not evolving much beyond simple hook-and-cable technologies. But with greater numbers of U.S. soldiers returning from Iraq and Afghanistan with missing limbs (fatalities were down thanks to improved armor and medical care), the U.S. Defense Advanced Research Projects Agency sponsored the Revolutionizing Prosthetics 2009 program, aimed at developing a fully articulated, neutrally integrated artificial arm. Dubbed by the media as the “Manhattan Project for Prosthetic Limbs,” it consists of a multidisciplinary team from more than thirty organizations across the United States, Canada, and Europe, led by the Johns Hopkins University Applied Physics Laboratory.

The Modular Prosthetic Limb System is the team’s latest bionic-arm prototype. Made of lightweight carbon fiber and high-strength alloys, the arm has twenty-five degrees of freedom, or joint motions (the human arm has about thirty), closely mimicking the speed and dexterity of a natural limb. A wide range of neural integration strategies are being tested to control the arm and restore sensory feedback, from injectable myoelectric sensors—wireless devices the size of a grain of rice implanted in muscles of the remaining limb, which integrate directly with the nervous system to transmit signals instructing the prosthetic’s movement—to more near-term methods such as targeted muscle reinnervation, which allow for “thought controlled” prostheses. This approach reroutes nerves that once controlled the lost limb to unused muscles nearby, sometimes using chest muscles; when the brain tells the arm to move, the rerouted nerves create a contraction that provides an electrical signal interpreted by the prosthetic limb, making it move in a natural manner. The prototype is modular and configurable to a patient’s injury, and cosmeses, or skin coverings, feature simulated pores and hair to mimic the natural appearance of the native limb.

improving wireless signal strength

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