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In traditional short-haul microwave transmission (that is, line-of-sight microwave transmissions operating in the 18 GHz and 23 GHz radio bands),RF design engineers typically are concerned with signal aspects such as fade margins, signal reflections, multipath signals, and so forth. Like an accountant seeking to balance a financial spreadsheet, an RF design engineer normally creates an RF budget table, expressed in decibels (dB), in order to establish a wireless design. Aspects like transmit power and antenna gain are registered in the assets (or plus) column, and free space attenuation, antenna alignment, and atmospheric losses are noted in the liabilities (or minus) column. The goal is to achieve a positive net signal strength adequate to support the wireless path(s) called for in the design.

The race to create tiny wireless sensors that could monitor anything from pressure in the eyes and brain to the stability of bridges appears to be heating up. Earlier this month, IEEE Spectrum reported on two approaches to creating an almost-indefinitely-running sensor using piezoelectric systems to convert tiny vibrations into power. Now, another team from the University of Michigan has created an alternative approach that uses solar power to keep the sensor running autonomously for many years.

In addition to voice connectivity, digital cellular wireless networks such as GSM and its enhancement, GSM-EDGE, can now provide increased data speeds up to a (theoretical) limit of 384ﾠKbps. Third generation mobile networks, such as CDMA2000 and WCDMA or UMTS (Universal Mobile Telecommunications Standards) and TD-SCDMA (China only) are currently being deployed worldwide. These systems offer services such as video streaming, Internet browsing and, by using a technique called High Speed Packet Access (HSPA), they can in theory deliver downlink speeds up to 14,4 Mbps.

Cellphone carriers are racing this year to implement 4G wireless networks so that future smartphones will have access to a fire hose of data. But the towers and infrastructure the carriers are putting in place may ultimately facilitate as many connections with appliances and electric meters as they do downloads of movies and music. The electricity grid, in other words, may be jumping from no G to 4G—and rather soon, according to analysts.

You might think that some devices in the modern age have reached their maximum development level, such as the common desk-lamp, but you would be wrong. Natan Linder, a student from The Massachusetts Institute of Technology (MIT) has created a robotic version that can not only light your room, but project internet pages on your desk as well. It is an upgrade on the AUR lamp from 2007, which tracks movements around a desk or table and can alter the color, focus, and strength of its light to suit the user’s needs. The LuminAR comes with those abilities, and much more. The robotic arm can move about on its own, and combines a vision system with a pico projector, wireless computer and camera. When turned on, the projector will look for a flat space around your room on which to display images. Since it can project more than one internet window, you can check your email and browse another website at the same time.

To paraphrase helicopter pioneer Igor Sikorsky: If you're in trouble, an airplane can fly over and drop flowers, but a helicopter can save your life. It can deftly maneuver through tight spots and alight in remote places. It can float next to a mountain to search for the lost. And the best sound a wounded soldier can hear is that telltale rotor beat, just minutes before being evacuated to a hospital. When roads are impassable, bridges have been destroyed, and the electricity has been knocked out, helicopters can still deliver supplies and rescue people.

With the consumer demand for richer content and its resultant , increasing high data bandwidth continuing to drive communications systems, coding for error control has become extraordinarily important. One way to improve the bit error rate (BER), while maintaining high data reliability, is to use an error correction technique like the Viterbi algorithm. Originally conceived by Andrew Viterbi as an error-correction scheme for noisy digital communication, the Viterbi algorithm provides an efficient method for forward error correction (FEC) that improves channel reliability. Today, it is used in many digital communications systems in applications as diverse as CDMA and GSM digital cellular, dial-up modems, satellite, deep-space communications and 802.11 wireless LANs. It is also commonly used in speech recognition, keyword spotting and computational linguistics.

It’s hard enough to set up a reliable wireless network at home on Earth, let alone space. I harbor a personal grudge against my two-foot-thick 19th century brick/plaster wifi-killing walls and don’t get me started with my router or my ISP. So how does NASA connect with the ISS 300 to 400 kilometers above the Earth travelling at nearly 28000 km/h? In this case, engineers took advantage of the station’s existing communication link, which relies on the Ku radio band. The Ku band is the most common portion of the frequency spectrum used for satellite communication and is not reserved for restricted use. Among the companies that use the Ku band for commercial purposes are satellite internet providers and news networks broadcasting on satellite from remote locations.