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Comment Re:Question about "Doppler Dilemma" (Score 1) 69

It's easier than that - use two blocks of different repetition frequencies (which gives two different Nyquist velocities), get two velocity readings. Some basic number theory will get you the right answer.

Using two different carriers is going to alter the Nyquist velocity by such a small amount that it's not worth doing. Unless the carriers are very widely separated (go from say, 2.7 GHz to 5.8 GHz) but this requires a wideband (and necessarily low gain) antenna.

That's not to say that FHSS is not used by weather radar - its purpose is to improve the quality of measurements by increasing the number of statistically independent samples that get averaged together.

Comment Re:It's not just the rubber parts... (Score 1) 375

There's also the effect of water absorption causing corrosion to metal parts, and promoting water absorption in certain plastic fuel tanks. The latter has resulted in a lawsuit with motorcycle manufacturer Ducati, where they agreed to replace the tanks that were swelling and in some cases, rupturing due to water absorption. This only happened in the US, after E-10 fuel became popular. Regular octane does not absorb water.

My Ducati's past warranty, so the tank replacement offer doesn't cover me, once my tank swells or ruptures, I'm hosed.

Comment Re:LOL, welcome to united states of hurrdurr (Score 3, Interesting) 208

I agree - the same is true here in Colorado, where land owned by Colorado State (a land-grant university) has been open to drilling for several years already. The university owns lots of land, often many tens of miles away from the main campus, for such things as experimental farms, aircraft hangars and radar sites. Most of them have been drilled using the "horizontal" approach, so no equipment directly on site. I know this because I work on one of the remote sites, and was around when they drilled some 500 feet away from my building. The oil company folks came over and explained that we may hear odd sounds when they did the frakking (I didn't). The university has made quite a bit of money off the wells, which translated to no student fee increases for a couple of years (this year was an exception, though).

Comment Re:Replace, or augment? (Score 1) 636

Even *if* you posit a dystopian future where the $BEC controls everything, there will *still* be PCs, because *someone* will still have to produce data. They may become much less common, but a PC, or a PC-functional device, *will* be necessary.

My worry is that this same phenomenon will lead to less data/content being produced. We're in a situation now where PCs are in virtually every home, every kid has access to one, and ones who are curious/lucky enough will stumble upon some interest of theirs that they can use this hardware to explore (examples: home recording studios, 3D modelling, CAD of various kinds, software development tools.) In a tablet-and-smartphone world, PCs will get expensive, and out of the reach of most kids/amateurs, who'd have no opportunity to explore their creativity.

Comment Re:useful.... (Score 1) 161

I'm not referring to searching through the data to make a detection, yes computers are awesome at that. Just making the measurements over an appreciable fraction of the sky with such accuracy would take a long time. It has its applications, for example when observing the space shuttle (you only need to search a small volume around the shuttle) or when tracking ballistic missles for interception (which is the original purpose for this radar system). So to obtain useful update rates (say, once every minute) at such high resolution, you will need an astronomically large number of radars. If you scale back the resolution, though, this is achievable, and has in fact already been implemented. Disclaimer: I was peripherally involved in the CASA project.

Comment Re:useful.... (Score 1) 161

If you have a radar that is sensitive enough to see individual rain drops, you should easily be able to see the low-RCS (also called Stealth) aircraft. They are not invisible, just *less* visible than traditional aircraft. Notice the details in the article, though: these measurements were made at a range of 2 km from the radar, over a volume the size of a small bus. Setting aside the very short range, to search the entire sky with a resolution that high would take a very long time.

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