ACE - Antenna Centre of Excellence. Navy orders shipboard software-defined radio systems from General Dynamics in $146.3 million contract. Smart home sensors use electrical wiring as an antenna. Smart homes of the future will automatically adapt to their surroundings using an array of sensors to record everything from the building’s temperature and humidity to the light level and air quality. One hurdle impeding the development of such intelligent homes is the fact that existing technology is still power hungry and today’s wireless devices either transmit a signal only several feet, or consume so much energy they need frequent battery replacements. Researchers have now developed sensors that run on extremely low power thanks to using a home’s electrical wiring as a giant antenna to transmit information.
The technology devised by researchers at the University of Washington and the Georgia Institute of Technology uses a home’s copper electrical wiring as a giant antenna to receive wireless signals at a set frequency, allowing for wireless sensors that run for decades on a single watch battery. The device is called Sensor Nodes Utilizing Powerline Infrastructure, or SNUPI. Spectrum: Technology to Talk to Trapped Miners. NIOSH eventually came up with two competitive solicitations for primary communication systems, which it defines as those designed to operate in the conventional radio frequency band (from a few hundred kilohertz to a few gigahertz). Miners either carry handheld radios or wear radio tags. NIOSH awarded a contract to Pillar Innovations of Grantsville, Md., for its rugged leaky-feeder system. It consists of a coaxial cable with openings in the insulation along its length, which allow it to give off and pick up signals.
The cable loops down into the mine and back to the surface. The other contract went to L-3 Communications, in Chantilly, Va., and Innovative Wireless Technologies, in Forest, Va., which together commercialized a wireless mesh communication network they call Accolade. But at best, conventional radio signals only propagate perhaps 300 to 600 meters down a coal mine tunnel, says Snyder. He also notes that time wasn't on the engineers' side. Millimeter-wave communication Over 84 Kilometer Range Using Panasonic Gallium Nitride Device. What Is Real 4G cellphone Communication Technology.
Pages Home July 14, 2010 What Is Real 4G cellphone Communication Technology Email ThisBlogThis! Share to TwitterShare to FacebookShare to Pinterest Ad Support : Nano Technology Netbook Technology News Computer Software Emerging mobile technologies Wimax and LTE and HSPA+ are advanced 3G or proto-4G but are not real 4G 4G will be technically defined by what the ITU qualifies as IMT-Advanced (with IMT 2000 being 3G), neither LTE nor WiMAX look to actually be 4G. 802.16m (802.16m Advanced Air Interface with data rates of 100 Mbit/s mobile & 1 Gbit/s fixed is an in progress standard) and LTE-AdvancedA will make the grade as true 4G.
Posted by brian wang at 7/14/2010 Labels: broadband, cellphone, future, wimax, wireless Please enable JavaScript to view the <a href=' Links to this post Create a Link Newer PostOlder PostHome Subscription Options Get Updates by RSS Read latest headlines in your favorite news reader Disqus comments Most Discussed Powered by Disqus Google+ Badge Blog Archive. Unit 2. Radio-Communications Theory. 21. Radio-Wave Creation and Propagation N this unit we briefly look at the historical development of radio communications and introduce the principles of electromagnetic (EM) radiation. Well also discuss the characteristics and properties of radio waves, and take a detailed look at the electromagnetic spectrum. From the first radio transmissions between St. Lets start by defining communications as a means or system by which we exchange our thoughts, opinions, information, and intelligence with others. Most of our civilizations great discoveries and inventions were made accidentallynot so with radio. 406.
The 1800s. The next significant stage in the process of message transmission was the development of a system of communication called the wireless. During the last part of the 19th century, a German scientist, named Heinrich Hertz, performed a series of experiments based on Maxwells theories. The 1900s. As you can see, radio communication has changed markedly over the last century. 407. Radio-Frequency Communication. 31. High-Frequency (HF) Communications N this unit well examine discuss specific aspects of radio communications across the radio-frequency band of the electromagnetic spectrum.
Since HF is the primary mode of our communications well look at it first. Specifically, well cover examine HF wave propagation, the ionosphere, and its effects on propagation. Well also examine HF engineering ideas, limitations on the use of HF, and satellites and their effect on HF communications. Next, well look at the lower frequency bands and the upper frequency bands. Again, well examine wave propagation and limitations on the use of these frequency bands. Weve been using high-frequency (HF) communications for many years. As more reliance was placed on satellite communications, we discovered it wasnt a perfect system.
In your AF career you will will learn more about the art of HF communications. 413. The troposphere. The stratosphere. The ionosphere. Formation. Structure. D layer. Figure 31. Figure 32. 414. Antennes. SBIR/STTR Interactive Topic Information System (SITIS)