Thursday, August 10, 2006

The Pawnee connection - Part 2

Having poured in liberal amounts of blood, sweat and tears, we got the radar up and running, complete with calibrations. And mostly moth-free (hmm, now there's a good corporate slogan...)

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That's the signal processor after I set it up. From top to bottom, it now holds the test source, high-precision GPS-derived timebase from which radar timings and frequencies are synthesized, antenna position indicator, antenna control, main signal processor, a monitoring console, the digitizer computer and the transmitter control unit. The second pic has a clearer view of my baby, the transmitter control unit... yes, I'm really proud of it :)

Not shown is a gigabit network switch to hook all of this stuff together, and a KVM switch for the signal processor and acquisition node.

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Here's some of the data collected by Pawnee today. Ignore the "radar name" field, that's a software bug. The first pic indicates the signal strength (which gives an idea of the rainfall rate), the second indicates the radial velocity, ie, how fast is the rain moving towards/away from the radar. As Murphy's law would predict, we have a working radar but no rain :-/ Most of the weak echo seen is from so-called "clear air" echo: insects, birds and airborne dust. Note the velocity gradient, this means that the wind is blowing in a NE-SW direction. The little white cross indicates a tiny localized storm.

I know, I know, I need a life. I left mine in my other trousers.


Grafxgurl said...

isnt it cool to watch something that youve put tigether actually work!!

i like the data pics.. well lol speaking like a complete designer... with eclectic tastes!

Jim said...

Totally, and when it matches theoretical expectations, that's even better.

You may like the radar pictures of more interesting storms, like the supercells that sometimes crop up around here. There are a few cases where we do vertical sections through the supercells, it's quite interesting to see the storm's features show up on the radar.