So these are all time shared links right? So what modulation and baud rates do you utilize ?
So these are all time shared links right? So what modulation and baud rates do you utilize ?
USAF - 1989-2011
For the backbone links we are using one of three bands depending on the situation. 5.8GHz, 11GHz, or 24GHz microwave shots, ranging anywhere between 16-2048QAM modulation rates. The 5.8GHz and 24GHz are license free, but the 11GHz is licensed. Depending on the customers preference, there are a host of options for this. I haven't found a need for one suppliers 4096QAM, nor a customer that wants to spend for it.
The last mile communication links are all Xetawave 900MHz unlicensed radios running multispeed multipoint, with an allowed range of 884kbps - 2651kbps (BPSK, QPSK, and 8PSK). We used to use FreeWave radios, but have since moved away from them.
This end users devices are a mix of Totalflow's, ROC's, and a few small name PLC/well controllers. Other customers have Allen Bradley, Bristol, Siemens, Ferguson, PCS, etc... (We see a lot of random gear due to being in so many vertical markets. We focus on being the experts on the wireless side and work/partner with people that know the PLC/RTU side better, if no one wants to partner we can do most of it, but it's not our forte. This brings a much better solution to the end user.)
Generally for serial devices in the field (old PLC's/RTU's/Flow computers), we run them at the max serial baud rate they are capable of. A few fields we have radios in still have devices that are limited to 1200bps. With RS485, we generally run 19200-38400, depending on the radio link (the better the link the faster we'll run). With RS232, if we have a full complement of control lines available on the device (they are all there on the radio), we'll run 115200.
I was just kidding. I get loopy after a 13 hour graveyard shift. Probably should refrain from posting at that time.
I was just kidding when I read this thread and didn't post anything.
"There are no finger prints under water."
Thanks for the scada setup explanation....in a previous life I used to do rf analysis, and every know and then some of that stuff would pop up...
USAF - 1989-2011
Sure.
The RF world is still fun for me (15+ years later), since I get to design big stuff like this, and then implement it.
Older Picture, but the most interesting immediately available. In this one, I'm hanging out at 120' working on a PTMP 3.65GHz Access Point.
0918141517 by ARNEWB, on Flickr
Last edited by Grant H.; 05-01-2016 at 21:44.
Awesome. I want to try something that high.
"There are no finger prints under water."
Hey Night Crew.![]()
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Does this count as night crew?
Probably be up for a while. Then I have a meeting with a customer at 6, an hour from my house... Maybe I should try the napping thing from the other thread... LOL.
Making a Raspberry Pi 3 into an OpenVPN server. Should be straightforward, but who knows. The last time I played with OpenVPN I never could get a client to connect properly...