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Submission + - FCC Lets Radar Company See Through Walls (commlawblog.com)

DesertNomad writes: Attorney Mitchell Lazarus over at CommLawBlog gives a good overview of a new radar technology and the challenges of getting regulatory approval, which seemingly can be just as difficult as developing the technology itself.

Comment Kill Switches in the Silicon (Score 2, Interesting) 392

My experience is with very complex and extremely common silicon wireless transceivers, including RF, PHY, MAC, NWK and even applications functions. 6 to 40 mm^2 of extremely dense circuitry (millions to tens of millions of gates). It would be very easy to put into that a block that would be nearly undetectable and that would cause the transceiver to change its behavior when specific sequences are received over the air. In a major metro area, a single broadcast message could shut down tens of thousands of cellphones or wi-fi devices. For weapons that use that part, it could quickly be "Phaser on OVERLOAD!" That having been said, when we do a design and send the design files overseas to third-party fabs in Asia, it is hard for them to be able to modify anything since the finished part will be different than our design file. But, I suppose if you had the money, resources, and desire for total world domination, anything's possible.
The Almighty Buck

Submission + - For Your Health, Froot Loops? (nytimes.com) 1

DesertNomad writes: William Neuman of the New York Times reports today on a new food-labeling campaign called Smart Choices, backed by most of the nation's largest food manufacturers, which is "designed to help shoppers easily identify smarter food and beverage choices." The green checkmark label that is starting to show up on store shelves will appear on hundreds of packages, including — to the surprise of many nutritionists — sugar-laden cereals like Cocoa Krispies and Froot Loops. Eileen T. Kennedy, president of the Smart Choices board and the dean of the Friedman School of Nutrition Science and Policy at Tufts University, said the program's criteria were based on government dietary guidelines and widely accepted nutritional standards.
Wireless Networking

Submission + - The Price of Staying Connected at Hotels 1

theodp writes: "Wireless Internet access is hardly a rarefied luxury — it's free in cafes, parks, fast-food chains, campgrounds, and even gas stations. But you can still pay dearly for Wi-Fi access in upscale hotel rooms, where daily access can run between $9.95 and $19.95. 'Not all guests use it [Wi-Fi],' explained a publicist for Thompson Hotels, 'so to include it complimentary in the rate no longer makes sense with the consumer wanting the most attractive rates.' The fees are 'exorbitant,' counters attorney Randall Stempler. 'It should just be built into the rate, like electricity.' BTW, Thompson made HotelChatter's 2009 'perp-walk' of Wi-Fi offenders. Got any additions?"

Comment Thermoelectric converters not so efficient (Score 1) 214

You don't get much from thermoelectric conversion - in my business of wireless sensor networks you see a lot of offerings. The best stuff in the past couple years generates about 50uW/sq cm for a 5C difference. That's good enough for a wireless sensor hugging a tree, perhaps. Available power goes up for more thermal difference, but it's unlikely that anytime soon either BWM, Adui, or even Fnord, for that matter, will be replacing the inexpensive, reliable and robust automotive alternator with a pricey power-producing muffler. Well, maybe Fnord.

Comment Re:Not Really Software-Defined (Score 1) 97

Of course they're software-defined radios - just over a narrow class. All those standards are OFDM modulation (well, except for .11b, but other than that...). Once you have an engine that can do the data rates of 802.11n and the OFDM subcarriers of Mobile WiMAX, everything else is just changing over-the-air parameters and frame structures. And in terms of modifiable, it's unlikely the radios could go out of the assigned frequency bands, and given the state of the highly optimized engines in these chips, you're not going to be able to turn a WiFi radio into, say, a broadcast FM receiver or a cellphone. First, the systems aren't even remotely similar; second, the power consumption would probably be awful; and third, there's no money to be made by the chipset manufacturer in allowing that to happen. But a reasonable chipset manufacturer could certainly publish open driver specs that would allow you write drivers to manipulate timing, bandwidth, frequency, packet size, used subcarriers, power levels (as long as it remains Part 15 compliant) - anything that doesn't touch on the transmitter certification itself.

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