Tag Archives: Innovations

Cornell engineers invent two-way radio on a single chip

Many thanks to SWLing Post contributor, Tom Ally, who shares the following news via the Cornell Chronicle:

Engineers devise two-way radio on a single chip

Two-way communication requires, of course, both send and receive capabilities. But putting them in the same device requires a filter between the send and receive circuits to provide signal isolation.

Without a significant filter, communication would be impossible.

“Your transmit signal is [10 to the power 14] times stronger than your receive signal,” said Alyosha Molnar, associate professor of electrical and computer engineering (ECE). “That’s 100 trillion times stronger – that’s a really hard problem.”

But researchers in Molnar’s lab have offered up a solution.

Molnar and collaborator Alyssa Apsel, professor of ECE, have devised a method for both transmitting and receiving a radio signal on a single chip, which ultimately could help change the way wireless communication is done.

Their work is described in “A wideband fully integrated software-defined transceiver for FDD and TDD operation,” published online Jan. 27 in the Institute of Electrical and Electronics Engineers’ Journal of Solid-State Circuits. Doctoral student Hazal Yüksel and Dong Yang, Ph.D. ’15, are co-lead authors.

Separating the send and receive bands is difficult enough, but the problem is compounded by the ever-increasing number of bands in the latest devices. From GPS to Bluetooth to Wi-Fi, each band requires a filter to stop the strong transmit signals from drowning out reception.

Molnar and Apsel have come up with an ingenious way to separate the signals. Their idea lies in the transmitter – actually a series of six subtransmitters all hooked into an artificial transmission line. Each sends its signal at regular intervals, and their individually weighted outputs are programmed so that they combine to produce a radio frequency signal in the forward direction, at the antenna port, while canceling out at the receive port.

The programmability of the individual outputs allows this simultaneous summation and cancellation to be tuned across a wide range of frequencies, and to adjust to signal strength at the antenna.

“In one direction, it’s a filter and you basically get this cancellation,” Apsel said. “And in the other direction, it’s an amplifier.”

“You put the antenna at one end and the amplified signal goes out the antenna, and you put the receiver at the other end and that’s where the nulling happens,” Molnar said. “Your receiver sees the antenna through this wire, the transmission line, but it doesn’t see the transmit signal because it’s canceling itself out at that end.” […]

Continue reading on the Cornell Chronicle.

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KNL Networks is developing shortwave-powered global Internet access

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Earth

Many thanks to SWLing Post contributor, Steve T, for sharing the following news from Business Insider:

KNL Networks, based in Oulu, Finland, has been in stealth mode during the past four years while developing a revolutionizing system that enables internet connection anywhere in the world – even in the middle of the Pacific Ocean – without using expensive satellite systems.
Today, KNL announced the completion of its series A funding round. The funding amounted to more than $10 million making it one of the biggest Nordic series A rounds. Creandum is the biggest investor.

[…]Facebook and Google have been exploring the possibility of bringing internet to remote locations by relaying data through a network of balloons. KNL’s technology, on the other hand, proposes the opposite: incredibly long range signals, by sending internet protocol over the radio.

KNL’s technology is already being used to provide robust internet connections to ships on the Atlantic and Pacific Oceans, but can be used anywhere on the globe for many different applications.

[…]KNL’s technology relies on shortwave radio transmissions, which can transmit data for thousands of kilometers, for a fraction of the cost of a satellite system. Accomplishing this has required the innovation of long-distance high frequency radio systems. In comparison with satellite internet, the radio technology offers the additional advantages of being easier to use, always on.

Read the full article at Business Insider.

This is very exciting news, Steve!

I’ve always had confidence that inherent HF bandwidth and data integrity issues could be addressed with time as our receivers, codecs and digital signal processing improve with each iteration.

As I wrote in, Does Shortwave Radio Have a Future?, I’ve always believed that the shortwave medium could be leveraged for international digital/data communications, and should be. In my article, I focused on Radio Canada International (RCI), which was then dismantling their shortwave transmitter site:

[B]roadcasters should not dismantle their transmission sites as Canada is currently doing. Not only is the current service originating from these sites a more reliable form of emergency communications than the Internet, should a national disaster befall us; not only do they continue to provide a broad-spectrum mode of diplomacy; but should future digital communication modes find a way to take advantage of the HF spectrum as is now under discussion, this would be most unfortunate.

Imagine a wi-fi signal with a footprint as large as several countries, digital devices with tiny fractal antennas that receive this signal containing rich media (e.g., audio and video)––these are not science fiction, but highly plausible uses of these transmission sites, even within the next decade…

We’ll be watching developments at KNL Networks and reporting updates here on the Post. Follow the tag: Shortwave Internet

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BBG, take note: Shortwave radio distributes smartphone apps

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Many thanks to Andy Sennitt, who posted a link to this Mission Networks News article on Facebook.

Imagine being able to download an app…without the internet.

Well, it’s finally happened, thanks to shortwave radio. Broadcasting Board of Governors (BBG), take note: Faith Comes By Hearing (FCBH), a Christian organization that distributes Bibles in parts of the world where they are difficult to distribute, have a free smartphone app called Bible.is. The only problem is, the app wasn’t available in countries where there is no access to the Internet nor where authorities block the app…at least, until now. By using Trans World Radio’s Guam shortwave transmitter site, they have successfully “downloaded” this app to multiple smartphones in Thailand:

[D]ue to a major recent breakthrough by Faith Comes By Hearing (FCBH), they were able to deliver the Bible to an unconnected smartphone using shortwave radio towers over 3,000 miles for the first time ever.

Troy Carl, Vice President of FCBH, explains, “Yesterday, we were able to transmit file casting data packets from Guam all the way to Thailand using shortwave frequencies, and we were able to do that in partnership with Trans World Radio. So it was really quite exciting! Basically what we did is created one-way internet access turning that tower into a super WiFi router. And that’s quite a story because it’s never been done!”

To put it another way, Carl wrote this description in a recent post:

Just like the one you use everyday in your house, where you connect a data source (internet cable) and a power source (you plug it in) and the little antennas broadcast internet around your house (say 500 ft.) and you connect to it with your phone to read/listen/see the data it’s transmitting.

In Guam, we took a HUGE antenna, (supplied by Trans World Radio), hooked up a data source (a Bible.is app device), turned the power on (250kw) and sent the data into the air bouncing it off the ionosphere over 3,000 MILES!

Our team in Chang Mai Thailand, hooked up to this giant router with a proprietary decompiler. Then sideloaded the Bible.is app with all its content to multiple smart phones using a simple wifi broadcaster!

As I wrote in, Does Shortwave Radio Have a Future?, I’ve always believed that the shortwave medium could be leveraged for international digital/data communications, and should be, especially in countries under repressive regimes such as North Korea. In my article, I focused on Radio Canada International (RCI), which was then dismantling their shortwave transmitter site:

[B]roadcasters should not dismantle their transmission sites as Canada is currently doing. Not only is the current service originating from these sites a more reliable form of emergency communications than the Internet, should a national disaster befall us; not only do they continue to provide a broad-spectrum mode of diplomacy; but should future digital communication modes find a way to take advantage of the HF spectrum as is now under discussion, this would be most unfortunate.

Imagine a wi-fi signal with a footprint as large as several countries, digital devices with tiny fractal antennas that receive this signal containing rich media (e.g., audio and video)––these are not science fiction, but highly plausible uses of these transmission sites, even within the next decade…

FCBH’s innovation is simply a first step in this direction. If it turns out that this method is both accessible and affordable, this could truly pave a new road on the mobile information highway.

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