Search This Blog

Saturday, August 24, 2013

New atomic clock's precision 'groundbreaking'

As reported by CNN: If you follow scientific developments as if they were football games, this would be a good time to cheer "Tick-tick-tick-tick! Tick-tick-tick-tick! Go, clock, go!"

The reason for such enthusiasm? Researchers have released a study in the journal Science describing what they believe is the world's most precise clock.

You'd never need this level of precision for getting to work on time, but the clock could be used for scientific exploration and technological advancements in areas such as navigation systems, said study co-author Andrew Ludlow, researcher at the National Institute of Standards and Technology in Boulder, Colorado.

The rate of ticking of this timepiece -- known informally (and awkwardly) as the ytterbium optical lattice clock -- does not change by more than one part in 10^18, Ludlow said. In other words, if there is any variation in how a second is measured, it would be in about the 18th decimal place.

"The ytterbium optical lattice clock has demonstrated a groundbreaking, new level of clock stability," he said. "One could say that this is like measuring time over a hundred years to a precision of several nanoseconds."

How clocks work
Inside a clock is a mechanism that changes in some regular way, called an oscillator. Imagine, for example, a grandfather clock, whose pendulum swings back and forth denoting time. In a wrist watch there is often a crystal with an electrically oscillating signal.
Measurement between two ytterbium optical lattice clocks.  The researchers
built these clocks by trapping thousands of ytterbium atoms at high density.
Then they measured the activity of these atoms, which were kept at very cold
temperatures, using lasers.  This image shows how laser light, which is
pre-stabilized to an optical cavity, is used to independently excite two
ultracold ytterbium samples, each held in an optical lattice.  When comparing
the activity of the ytterbium atoms between the two samples (or clocks), the
researchers found very little differentce in ticking frequency between the two.

A particular number of "back and forths" corresponds to one second.

An atomic clock makes use of an electromagnetic signal -- in other words, light emitted at an exact, known frequency. At the core of the system, there is an atom. The light is used to excite an electron in the atom.

In this model, the excitation and de-excitation of an electron corresponds to a pendulum swinging right to left, but in an atomic clock, the "tick" denotes an unimaginably tiny fraction of a second.

The current gold standard for time is the cesium clock, a type of atomic clock that an international body of experts has used to define what is the unit of one second: About 9.19 billion oscillations. In this clock, a microwave light source is used to excite electrons in cesium atoms.

But the new atomic clock at NIST, described in the Science study, uses a different element: Ytterbium, atomic number 70. Optical light -- specifically, yellow light from a laser with a wavelength of 578 nanometers -- is used to excite the electrons of ytterbium atoms.

Whereas scientists talk about billions of oscillations per second in the cesium clock, oscillations per second in the ytterbium clock approach one quadrillion per second, Ludlow said.

The new clock is akin to a ruler that has markers for fractions of inches, compared to a ruler that only delineates inches. The first instrument would make more precise measurements.

The lattice of laser beams traps small numbers of
ytterbium atoms in pancake-shaped "wells."  A
yellow laser excites the atoms so that they switch
between lower (blue) and higher (yellow) energy
levels.
"You divide time into finer and finer intervals," Ludlow said.

In order to establish the precision of this clock, the scientists had to make two of them, to confirm agreement in the measurement of time.

The devices won't fit on your wrist, or even on your wall. Because of all the laser equipment and technology necessary for this level of precision, the atomic clock and all of its components occupy a space about the size of a dining room table, Ludlow said.

Efforts are under way to shrink the technology, however, particularly so that a version of it might be sent into space.

Potential uses
Researchers studying Einstein's theory of general relativity could make use of this clock to more precisely measure how time is different depending on the surrounding gravitational force.

Global positioning systems (GPS) already take this into account. Because they are farther from Earth than we are, and therefore experience less gravitational pull, their measurement of time as they orbit Earth is slightly different from what we perceive on the ground. A more precise atomic clock could measure the correctional factors even better.

Such clocks could also test alternative theories about the relationship between time and gravity.

There could be other applications for navigation and communications systems.

But you probably won't want one for your alarm clock. Ludlow said the total cost ranges on the order of a half-million dollars.

Accuracy
Although scientists have proclaimed that this is the world's most stable clock, they do not yet know as much about its accuracy. This is a subtle but important difference: The ytterbium clock has demonstrated incredible stability of measurement -- it always measures a second in the same way -- but we do not yet know if what it is measuring is a "true" second.

So, we'll have to wait to find out whether these clocks could be the most accurate in the world.

More research is needed. It's a story we hear time and time again.

Friday, August 23, 2013

If you could visualize Wi-Fi, what might it look like?

Wi-Fi is an energy field that is transmitted as waves.  This image
shows an idealized Wi-Fi data transmitted over a band that is
divided into different sub-channels, which are shown in red, yellow
green and other colors spanning the visual spectrum.
 As reported by the NY Daily News: Wherever we move around in a city, our bodies are passing through hundreds of electromagnetic waves. Artist and researcher Nickolay Lamm at MyDeals.com brought Wi-Fi, a certain type of wave, to life in these colorful images.

“I feel a lot of us take technology for granted and use it without appreciating the science that makes it work,” Lamm said in an email to The New York Daily News.
Lamm teamed up with Marilyn Vogel, a science professor at the National Hispanic University in San Jose, to help him visualize the invisible.

Data-transmitting waves, whether they come from radios, cell phones, or computers are essentially disturbances in our natural electromagnetic fields. The crest of Wi-Fi waves are understood by a computer as a 1. The troughs are equivalent to a 0. Ultimately, these chains of 1s and 0s form an intricate pattern that is then translated into the letters, numbers, and codes that make up websites.
Although color represents its own unique visible segment of the
electromagnetic spectrum, Lamm used red, orange, yellow, and other
colors to show the invisible Wi-Fi channels that make up the overall
Wi-Fi signal.  Wi-Fi fields are usually spherical or ellipsoidal.

“It’s kind of like a barcode,” Vogel told The New York Daily News. “It’s not really a pattern that the eye can detect, but a computer can.”

Wi-Fi waves are three to six inches from crest to crest--not as long as typical 'radio waves', but definitely not as short or as destructive as microwaves.

Routers, instead of sending out a single wave, take a range of wavelengths, chop them up and transmit them simultaneously. The average home Wi-Fi signal can project up to about 30 feet. They can pierce through walls easily, but water is an impediment. Plants and foliage can sometimes impede Wi-Fi signals.

The Wi-Fi that is available in public spaces is much more powerful and can transmit signals up to 150 feet. These boxes are everywhere in the modern city — strapped to trees, buildings, and lampposts.

That means that even though we can never see them, we are surrounded by these waves of data all the time.
Wi-Fi routers affixed to buildings, lamp posts and other objects
create a circular data field around them.  These antenna have an
omnidirectional signal that ideally extends equally in all
directions - until it is absorbed, reflected or 'canceled out'.
Cancellations or collisions between reflected waves - also called 'nulls'
 are like small holes in the overall network of electromagnetic
fields that comprise the Wi-Fi signal.

And since there is increasing demand among consumers for more connectivity, the amount of data in the air will just keep increasing.

Vogel says the takeaway from these images is about how humans play with the physical world to meet an increasing demand for digital connection. Consumers want access to more data and higher speeds.  But there is a limited amount of space on the electromagnetic spectrum and tech companies are fighting for spots.

“Given that the range of electromagnetic spectrum over which Wi-Fi can be transmitted is limited, the question is how we will meet increasing consumer demands for high speed data.”

Qualcomm Selling Omnitracs Transportation and Logistics Business

As reported by Truckinginfo: Qualcomm announced it has signed a definitive agreement to sell its Omnitracs subsidiary to Vista Equity Partners, a U.S.-based private equity firm.

Omnitracs was a pioneer in in-cab communication, developing one of the first widely used satellite tracking and communications system for truck fleets, and today offers a variety of fleet management and telematics solutions.

The acquisition will include all of Omnitracs operations in the United States, Canada and Latin America, including Sylectus and FleetRisk Advisors, which were acquired by Omnitracs in 2011.

Vista will purchase Omnitracs for $800 million in cash. The deal is subject to federal anti-trust review and approval. Qualcomm says the acquisition is expected to be completed during the first quarter of its 2014 fiscal year.

Vista chose to acquire Omnitracs because of its strong position, product offerings, loyal and satisfied customers, and its highly talented and devoted employees, said Qualcomm in a statement.

“Leveraging its experience with numerous other vertically oriented software companies, Vista is uniquely qualified to help position Omnitracs for continued growth and will enable the company to strengthen and expand its product offerings.”

“We are long-term investors in enterprise software, data and technology-enabled businesses that are committed to being leaders in their fields,” said Robert Smith, chief executive officer and founder of Vista Equity Partners, in a statement.

Vista Equity Partners currently invests over $7.1 billion in capital in technology-based organizations.

“Today, the opportunity for fleet management and telematics is evolving rapidly, and we believe Omnitracs is well positioned to continue its leadership position as a stand-alone entity,” said Derek Aberle, executive vice president and group president, Qualcomm Inc.

Bluetooth wallet alarms when cards disappear or the wallet is stolen

As reported by Fine Extra: A US start-up has taken to KickStarter to fund its Bluetooth smart wallet which links to the owner's phone and alerts them if their payment card is not returned.

The 3mm thick aluminium Ping card holder connects to iOS and Android phones (with Bluetooth 4.0 capability) and sends an alert reminding the user to put their card back in the wallet after each use.

The wallet also has a built-in speaker which beeps if someone takes it or the user's phone. If the wallet and phone lose connection, Ping not only sends out an alert but records the last known GPS location.

The wallet has a range of about 100 feet and the battery lasts for up to two years, after which it needs to be replaced for a "very small fee".

Having built working prototypes the inventors have taken to KickStarter to raise funds for full production, so far raising around $8,700 of their $30,000 target. When it goes on sale it will retail for $79.

Why Some Mobile Apps are Using Sound for Pay-by-Phone

Startups are using sound waves to let mobile gadgets transfer
data quickly and efficiently.
As reported by MIT Technology Review: Next time you take a taxi in New York City, there may be a new way to pay your fare. Instead of handing over cash, swiping a credit card, or—if you’re one of the few with a capable smartphone—tapping your handset on a near-field communication (NFC) reader, you could be able to settle up by pressing a button on a smartphone app that communicates using sound.

The new app, called Way2ride, is free for iPhone and Android from the payment service company VeriFone, which already provides payment processing systems for more than half of the city’s 13,000 yellow cabs. VeriFone recently acquired the underlying technology, called Zoosh, from a startup called Naratte (see “Ultrasound App Lets Almost Any Phone Pay”).
VeriFone is one of a number of companies using sound waves to transfer small amounts of data over short distances, which could make it easier to transfer money electronically, among other things. A well-funded stealth startup called Clinkle is said to be doing something similar (a spokeswoman for Clinkle had no comment for this article).
VeriFone's Way2ride application lets New Yorker's pay for a cab
by tapping their phone using sound.

VeriFone’s Way2ride app allows your phone to pick up an inaudible sound signal containing a unique code broadcast by a speaker in each taxi. The app sends this code to Way2ride servers, where it is matched with your cab, and your preset payment preferences are then sent to the cab over a cellular network and displayed on a backseat console. If you haven’t selected the auto-pay option, you can choose which card in your virtual Way2ride wallet to pay with and set a tip.

Zoosh could make its way into other payment terminals in the near future. “Anywhere we have a speaker and an entertainment system, like a gas station or in a taxi, it can work with that technology,” says Jason Gross, vice president of strategy and marketing for VeriFone Media, which is a unit of VeriFone.

The general premise isn’t new at all: it’s analogous to the tones traditional telephones emit when a call is placed over analog lines. Years later, we have much faster (and quieter) Internet connections, as well as short-distance communication systems like NFC and Bluetooth. However, some companies believe sound-wave data transfer is a good alternative because two of the prerequisites—a speaker and a receiver—are already so widespread, and the technology doesn’t require any special hardware or device pairing. That could make it easier for consumers around the world, including the millions who do not have smartphones, to do things like buy and sell goods locally. Sound can also be used as a simple way to let completely different devices communicate, which is becoming increasingly important as we split time between an ever-growing number of gadgets.

Another startup, Animal Systems, offers an app called Chirp that uses sound to let users share photos, links, and notes with friends; it could also be used to retrieve coupons in a store. While the method works only over short distances and can’t reliably move much data at a time—Animal Systems CEO Patrick Bergel says his startup aims for 97 percent success at ranges of three to four feet—the use of sound waves may at least serve as a useful intermediate technology. “It seemed like there was a sort of secret network waiting to be used,” Bergel says of the rise of sound as a data-transfer method. He says Animal Systems may also open up its technology to outside developers.

Sonic Notify (see “Startup Sends More than Music through Speakers”) has a technology called Adomaly that plays high-frequency sound waves through speakers or small dedicated beacons, which send a trigger to your phone. If your handset already has an appropriate app and you’ve opted to receive location-specific messages, the trigger prompts the phone to take an action. This could mean connecting to a server and grabbing a coupon for a product in front of you when you’re in a store, or accepting an invitation to a special event while you’re watching TV. Sonic Notify can also use low-power Bluetooth to communicate with users even if they haven’t paired their devices, but this version of Bluetooth is still not very widespread. Unless you’re using sound, “to get a large volume of people now and not three years from now, you really don’t have any other option,” says Sonic Notify’s CEO, Aaron Mittman.

Others are already developing tools to make it easier to communicate with sound. Boris Smus, a Google engineer, recently released an ultrasonic networking JavaScript library called Sonicnet.js, which uses the Web audio API to allow users to transmit and receive data via sound waves. So far, a handful of people are trying it out, he says, and though he’s not yet sure what results this will yield, he does feel it’s important. “The problem of multiple devices together in our close personal area network is a big problem to solve,” he says.


Yankee Group analyst Carl Howe says there’s “huge potential” for such technology because phones of all kinds are already primed to use it, which is not the case with NFC. However, he thinks it will have to be easy to use—perhaps a system enabled by something similar to the dedicated low-power processor on the new Motorola X smartphone, which is always on and listening for specific voice commands (see “Motorola Reveals First Google-Era Phone, the Moto X”). “There are pluses and minuses—audio clearly is going to be a tougher technology to use on a crowded conference floor than an electronic radio technology,” he says. “But it really depends on the environment and the application.”

High Tech Infrastructure: Why We Should Build a National Internet System Into the National Highway System

As reported by The Atlantic CitiesEarlier this month, The Daily Yonder, a well-named site about life in rural America, brought us this unsettling map of broadband availability, or lack thereof, in the country's remote counties.


Truth is, the connectivity of U.S. cities is nothing to brag about either. A 2012 report from the New America Foundation found that residents of major American cities pay more money for slower Internet service than their counterparts in major cities around the world. Case in point: in Hong Kong, roughly $35 gets you access to a fiber-optics network with 500 Mbps download speed; in New York or Washington, it gets you a cable network at 25 Mbps.
The point is that broadband service in the United States is neither what it could be nor what it should be. Yes, the vast majority of Americans have access to very basic Internet service, but here the devil's in the details. Too many rural residents lack even minimal access; too many big cities lack the competition that would create world-class service; and for whatever reason — be it access, cost, quality, or something else — 100 million Americans don't subscribe to broadband service at all.
Here's an idea to change that: let's build a National Internet System under the National Highway System.
The concept isn't a new one — it was most recently floated out there by Benjamin Lennett and Sascha Meinrath of New America in early 2009 — but it remains viable and merits a comeback. Lennett and Meinrath argue that broadband access is a basic public service every bit as necessary as good roads. Since 90 percent of the country lives within 5 miles of a national highway, and since utility infrastructure is already planted along highway rights-of-way, bundling the network is the simplest and surest way for service to reach everyone.
"Our idea was that you create this open infrastructure, so that anyone could come in and provide connectivity," says Lennett. "It would be a public asset along the highway system."
The obvious benefit of such a system would be its national scope. Rural regions that private providers might consider unprofitable and ignore would gain broadband access, but remote areas wouldn't be the only victors. So-called "middle mile" access would improve, too, meaning Internet service in smaller cities and towns wouldn't have to go out of its way to reach big interconnection hubs in major areas, leading to faster speeds.
The economic boost, meanwhile, could be gigantic. Private service provider competition would increase, especially in major cities; small businesses could count on fast and reliable access at a fair price; the telecommunications network in general would become more secure and robust. Imagine all the productivity advantages that Google Fiber is bringing to Kansas City, writ large across the country.
And let's not forget the Department of Transportation's push toward an intelligent transportation system. Connecting cars with traffic infrastructure via roadside networks has the potential to reduce congestion and increase safety in metro areas and beyond. Laying fiber along the national highways would facilitate the arrival of this "smart" roads system that DOT believes is the future of American car travel.
"You're going to need higher [broadband] capacity along highways anyway," says Lennett. "It's a heck of a lot cheaper to have some sort of public asset that the states and local governments can use, versus paying for it from a private provider."
Which brings us to the cost. A plan to pair broadband infrastructure with national highway construction or repair creates natural savings; after all, the Federal Highway Administration says that 90 percent of the cost of deploying fiber-optics is related to road work. Installing fiber (or, at the very least, pipe conduits to house it) during open road construction costs roughly $30,000 per mile. At a low-end cost of $3 million per mile of road, therefore, the plan only adds about 1 percent to each national highway project.
With those advantages in mind, Lennett and Meinrath estimate that a national broadband network could be laid along the entire national highway system for roughly $3.6 billion. In the great pie of transportation funding, that's a sliver.
Other efforts have been made in recent years to expand the U.S. broadband network, but while Lennett calls them "positive steps forward," he doesn't believe they've gone far enough. (Others agree.)
The National Broadband Plan of 2009, for instance, was mostly limited to policy recommendations and failed to encourage competition (which explains why incumbent providers like it so much). Proposed legislation requiring highway projects to install broadband conduit hasn't made it too far. The Obama Administration did issue an executive order last year calling for a "dig once" [PDF] policy to help promote broadband-highway coupling, but that still relies on private enterprise to do what it hasn't done to date: lay fiber everywhere.
So why not make the whole national internet system a public one, like the national highway system before it? At a time when elected officials are struggling to find a truly federal transportation goal, the concept might serve as a welcome rallying point. The government could sell some of its broadcast spectrum to foot the bill, but the user-pay model could probably work well, too — especially since people don't suffer the illusion that Internet access is free, unlike they do with roads.
"There is a really interesting parallel between transportation and broadband," says Lennett. "In the 20th century we needed to move cars, and in the 21st century we need to move bits."

Thursday, August 22, 2013

Making The World Less Safe For GPS Jammers

As reported by Strategy Page: The U.S. is building and testing more compact GPS anti-jamming systems for smaller (as small as 200 kg/440 pounds) UAVs. This is part of a program to equip all American UAVs, even the smallest ones, with more secure GPS. While all UAVs can be “flown” by the operator the GPS makes it a lot easier for the operator to keep track of exactly where his UAV is at all times and sometimes the UAV is programmed to simply patrol between a series of GPS coordinates. If the GPS jams or fails the operator can usually use the video feed to find landmarks on the ground and bring the UAV back to where it can be seen and landed.

While American troops have not yet encountered much (if any) battlefield jamming, the threat exists. The most tangible threat is from North Korea, which has long made, sold and itself used GPS jammers. Last year North Korea attacked South Korea with a massive GPS jamming campaign. The jamming began in late April, 2012 and continued for over two weeks. It took about a day for South Korea to confirm that the signal was coming from North Korea and was mainly aimed at the South Korean capital (Seoul). The jamming had little impact inside the city itself (the ground based jamming signal was blocked by buildings and hills) and was only noted by several hundred aircraft landing or taking off from local airports and over a hundred ships operating off the coast. In all these cases the ships and aircraft had backup navigation systems, which were switched on when GPS became unreliable. This is how navigation systems, especially those that rely on an external (satellite) signal are designed.

This is the third time North Korea has used GPS jamming against South Korea. For most of March, 2011, North Korea directed a GPS jamming signal across the border towards Seoul. A separate jammer has been directed at cell phone traffic. The GPS jamming signal could be detected up to a hundred kilometers south of the DMZ.

The usual response to GPS jamming is to bomb the jammers, which are easy to find (jamming is nothing more than broadcasting a more powerful version of the frequency you want to interfere with). But such a response could lead to more fighting in Korea, so the south protested and refrained from responding with force. The jamming is a nuisance more than a threat and most military equipment is equipped with electronics and other enhancements to defeat it. The North Korean jamming confirmed what was already suspected of them. So now, South Korean and American electronic warfare experts have an opportunity to study the effects of jamming on a large metropolitan area. It is causing intermittent problems for users of GPS devices and many more cell phone connectivity problems. There were briefer and less powerful jamming incidents in August and December of 2010.

Meanwhile, this is old news for the U.S. Department of Defense which has spent most of the last two decades developing anti-GPS jamming technology. For years military aircraft have been equipped with complex and expensive GPS receivers that will usually continue to work even if they are being jammed. There are several ways you can defeat attempts to jam GPS signals. While some of the methods are well known, others are classified. No one has successfully used GPS jammers in combat yet but the potential is there. Now the North Koreans are giving large scale demonstration of GPS jamming.

Anti-jamming technology is more complex. None of the major players (the U.S., Russia, China, Israel, and several other industrialized countries) are talking and for good reason. If you don't know what techniques the other guys are using, you can't deal with them.

China and Russia are both selling GPS jammers. Six years ago China brought to market a powerful, truck mounted, GPS jamming system. These "GPS jamming vans" are meant to create a protective "bubble" over an area the van is in the middle of. Sales have been slow.

A year before the 2003, invasion of Iraq, it was believed that Saddam had bought many GPS jammers, to deal with U.S. JDAM GPS smart bombs. The JDAM has a backup inertial guidance system, so that if the GPS signal is jammed the less accurate inertial guidance system takes over. The inertial guidance (INS) will land the bomb within 30 meters (92 feet) of the target while GPS gets to within 10 meters (31 feet). The U.S. Air Force does not discuss what, if any, jam-proofing it is doing for its JDAM bombs. The Iraqi GPS jamming efforts had no significant effect on the 2003, campaign.

There are several approaches to defeating GPS jamming, and knowing which one each American GPS guided weapon uses makes it easy to develop a way to jam the "jam-proof" GPS. So the U.S. Air Force is understandably reluctant to discuss what they are doing. Given the cost of jam proofing all existing GPS weapons, it's more likely that jam-proof GPS weapons will only be used against targets where the GPS accuracy is vital. Against most targets the accuracy provided by the inertial guidance system will do. Also note that you can bomb GPS jammers with a bomb equipped with a guidance system that homes in on a GPS jamming signal. For that reason it's thought that any use of GPS jammers will involve dozens of jammers in each area so protected. The GPS jamming has no effect on the even more accurate laser guided bombs, and some countries buy smart bombs with both laser and GPS/INS systems.