Author: RB

— Reader Terry points to this article in Aviation Week on preliminary findings that UWB interferes with airplane Instrument Landing Systems:

Ultrawideband transmitters temporarily “knocked out” the instrument landing system and traffic-alert collision avoidance systems during some very preliminary tests by NASA Langley.

The test was conducted with UWB transmitters inside the aircraft, where low signal levels are still sufficient to interfere. The Economist article below says this isn’t supposed to happen, but it does. UWB would be an ideal terrorist weapon in its current configuration, so it’s a no-go, except where locked-down.

— Yahoo! News – Tech Titans Guarding Wi-Fi Secrets reports on second-generation WiFi access points:

Intel is taking a different approach with its “soft AP” — or soft access point — initiative. It is aiming to split an access point between Windows and a chip for 802.11 cards geared to real-time processing.

Compaq has offered a soft AP for a while, and it’s no big trick; Intel’s just has a slightly beefed-up chipset behind it, making every PC its own Access Point, and consequently building a denser mesh. That was the idea behind DCF all along. Good boys, Intel.

— The Economist does a nice survey of some emerging Wireless Data technologies, picking up where WiFi leaves off:

IT IS more than a century since Guglielmo Marconi pioneered wireless data transmission. Yet, if the current pace of innovation in the field is anything to go by, wireless technology is still in its infancy.

Inventing the 802.11 MAC protocol was the best thing I’ve done so far. One of the interesting enhancements is the use of multiple antennas, allowing data to go farther and faster:

So instead of one omni-directional antenna, many base-stations now use three-directional antennas pointing in different directions, each of which covers a 120? sector.

Multiple antennas is a trivial enhancement, most useful for base stations because in that application, and only there, increased power-consumption isn’t an issue, as it would be in laptops, for example.

Mesh networks – where every base station is not only a local access point, but a router, are a significant innovation, directly competing with DSL and cable modems for a fraction of the cost:

For providing fixed-wireless access, the mesh approach is technically superior to the traditional ?point-to-multipoint? radio approach in a number of ways. For one thing, it requires much less power. Rather than using high power to get around obstacles, mesh networks offer multiple paths from one node to another; with systems typically being self-configuring so that, like the Internet, traffic is sent by the quickest route. Also like the Internet, mesh networks are robust and can be scaled up easily.

And then we have ad-hoc networks and Ultra-Wide Bandwidth networks filling out the puzzle:

UWB marks a radical departure from existing wireless technologies because, rather than transmitting and receiving on a particular radio frequency, it involves transmitting very short pulses on a wide range of frequencies simultaneously at low power. Such pulses, which are typically less than a billionth of a second long, pass unnoticed by conventional radio receivers, but can be detected by a UWB receiver.

UWB is intriguing because it can coexist in licensed spectrum with traditional analog services, thus enabling more efficient use of bandwidth than either 802.11a or b. There’s a lot more growth in the wireless pipeline than the meager efforts underway at chip companies today, most of which are simply imitative.

Link courtesy of Letters from Exile.

— Transterrestrial Musings observes a high correlation between dodgy accounting and Andersen clients. There’s a certain irony in this, because Andersen used to position itself as the most principled of accountants, but that posture went by the wayside during the Clinton years when Go-Go was king. I heard a professor lady on the radio talk about her tenure at Andersen, who hired her to teach Business Ethics. The punch line is that she sold courses to Andersen customers, but she couldn’t get Andersen itself interested in the concept except as a profit center. It seems to me that certain prosecution for cowboy bean-counters is the cure.