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Comment: Re:and how do they track users across muilt units? (Score 2) 43

by Schrockwell (#46426029) Attached to: Stanford Team Tries For Better Wi-Fi In Crowded Buildings
On a university network, every networked device is usually registered by its MAC address, which is tied to that student's school-wide login for tracking purposes. The university already knows everything you do. I assume the same would be true over this public WiFi architecture.

I tried to get around this one time by spoofing my MAC with one from a library computer. THAT didn't go over so well. Since I was using the personal WiFi in my dorm room (stupid, I know), they knew exactly which network spigot it was coming from. Alarms went off all over their monitoring tools. Luckily I had a friend in IT who saw it, laughed, and told me to not do it again.

Comment: First astronauts to land in 2025 (Score 5, Informative) 216

by Schrockwell (#45821769) Attached to: Mars One Selects Second Round Candidate Astronauts
From TFIndiegogo: "This 2018 mission will be the first in preparation for human landing. The first Mars One crew is scheduled to land in 2025, with additional crew landing every two years. Before that, Mars One will have established a habitable, sustainable outpost via multiple missions scheduled between 2018 and 2022."

Comment: 7.3V? Psh! (Score 3, Insightful) 216

I can build up a couple kilovolts by scuffing my shoes on the carpet.

Also, sure it might be 37% efficient, but do you realize how SMALL the density of RF energy is? The Friis transmission equation gives you some idea: it decreases by the square of the distance away from the source, due to that power spreading out in a sphere. When you start off with only a couple mW of power and an omnidirectional antenna, there isn't much power left to harvest when these tiny receiving "metamaterial" antennas are even just a few feet from an access point.

Comment: Dymaxion Mini (Score 1) 93

by Schrockwell (#43038011) Attached to: 3-D Printed Car Nears Production
The design for this car appears to be inspired by R. Buckminster Fuller's Dymaxion car. It features a similar aerodynamic "teardrop" shape and the same three-wheel design, although his was much bigger (and more fuel-efficient than most of today's cars). I'm surprised this wasn't mentioned anywhere in the article. There is a great video of the car doing laps around a traffic guard. Bucky was in the Navy and was fond of sailing, and he said that having the single wheel in the back made it feel more like you were turning a rudder on a ship than steering a car.

Comment: A problem for satellites, too (Score 2) 224

by Schrockwell (#42839241) Attached to: No Wi-Fi Around Huge Radio Telescope
This is also a huge problem for spaceborne radiometers that observe the Earth's surface (example paper). A radiometer is essentially a very sensitive receiver, and there are portions of the UHF and microwave spectrum reserved specifically for scientific research so that terrestrial stations don't interfere with the measurements. Unfortunately, interference may occur from transmitters directly in the band, from adjacent channels, or inadvertent harmonics from poorly-filtered transmitters. Pinpointing and correcting these sources is a logistical nightmare, especially when you have to deal with every individual country's RF regulators.

Comment: I don't like the sound of this... (Score 2, Informative) 116

by Schrockwell (#28778891) Attached to: Radar Could Save Bats From Wind Turbines
The rise of wind farms has already led to complications with current NEXRAD weather radars, and these radars don't even scan that close to the surface â" 0.5 degrees is the lowest tilt. I can only begin to imagine the complications of wind farms interfering with military radars which scan much closer to the Earth's surface.

Now they want to point some sort of radar at a complicated source of ground clutter that's already difficult to detect and remove? I don't see how that's going to fly (no pun intended).

For more information: http://www.roc.noaa.gov/windfarm/how_turbines_impact_nexrad_user.asp
