New Twist for This Hobby -- GnuRadio

[Cold Winter]

Attention folks, ( and suppliers as well I suppose );

Check out this site;

GNU Radio

This is a software radio ( open source ) that interfaces to various GNURadio specific transceivers including ones that operate in the band pass of your typical FTA LNB

S/W and H/W schematics are all there open source. :shocked

The implication here, is that you could pole mount one of these "radios" on your dish mount and operate the whole shebang over your home LAN using power over Ethernet and any internet appliance in the house...

There are multiple transceivers that can be supported, which implies a single point OTA TV, AM/FM Radio, CB, FRS and other capabilities ( it is S/W controlled after all ) as well as WiFi ( a/b/g/n ) and more importantly "WhiteFI" .

Now if our suppliers could get a source for this stuff and get the price under say $100, I'd say things could take a very interesting turn here. Don't you agree?

Something to look forward to in the New Year eh?

.

 

[Anole]

I read the "Getting Started", and the "FAQ", and nowhere did I find a definitive discussion on what it was for.
It sounds like a solution looking for a problem.

If it's somehow relevant to FTA Satellite, please share. -
Not that it has to be, of course, but I'm a little lost.

 

[SatelliteAV]

Please describe what and how this might be used in my home.

I also have read the FAQ and not understanding the potential uses or applications.

 

[zamar23]

It looks like it can replace band tuner and (de)modulation specific hardware like cellphone or sat card, making a PC universal radio device by using a universal or broader purpose card and specific for each application software add-ons. "The Universal Software Radio Peripheral, or USRP (pronounced usurp) is designed to allow general purpose computers to function as high bandwidth software radios. In essence, it serves as a digital baseband and IF section of a radio communication system."

 

[Sadoun]

Ok, I am lost here. Say what?

 

[pedrogarcia]

Zamar - That's as I read it, I seem to remember this being used as an RF hacking device.

I think someone has too much time on their hands and, re inventing and over engineering the wheel

 

[pendragon]

This is the other end of the spectrum from where most of us reside. We buy receivers implemented in hardware. Whenever some new standard comes along, be it DVB-S2, H.264 or 4:2:2, we dig into our pockets and buy the next generation unit. For those of us who dabble in more than just C-band and Ku-band, we repeat this story for each band we target. And then there are Hams who want to also transmit.

The premise of a software defined radio is to drastically simplify the hardware and generalize it to cover multiple bands with receive/transmit functions. The smarts all reside in PC-based software. The hardware does no demodulation. It simply captures the portion of the spectrum you want to receive (or the converse for transmitting) with A/D converters. The software does the demodulation (or modulation for transmitting) and any other specialized processing that is required.

Thus when a new type of signal is introduced, there is no reason to buy new hardware. The software is updated to handle whatever new processing is required. In addition this allows a lot of control of the signal processing. We're pretty much used to letting our receiver make the choices for optimizing reception. In fact, when these choices are built into hardware, there's usually not much that can be done. However with a software-based signal processing, there are many tricks and techniques to improve reception conditions and mitigate interference.

The basic hardware receiver/transmitter is pretty much just an interface between the computer and the A/D and D/A converters. There are daughtercards that plug into the base system that will downconvert/upconvert to the actual IF or RF required. For example, one would need the DBSRX daughtercard for FTA purposes, as it downconverts our friendly L-band (we use 950-2150 MHz, the card actually does 800-2400 MHz, which covers other applications beyond just FTA). I don't know the state of the software, but its pretty easy to develop the various components or piece them together from existing code. Thus one could build a single receiver system that could handle analog, DVB-S, DVB-S2, DSS, DCII, etc. and when something else comes along, it would be straightforward to add that, too.

This is probably not that useful for most people, but if you wanted to push the limits of your FTA system, this would be one way to do it. One could likely get very close to the theoretical limits of reception in terms of CNR. For example if you wanted to perform aperture combining (using more than one dish to cancel interference from adjacent orbital positions, cross-polarization cancellation, or improve CNR) this would be an effective path to take. And if you are interested in receiving other signals beyond FTA, and possibly transmitting (as a Ham) this one system could act as a centerpiece.

 

[Bill_KY]

Those of us who dabble in Linux, there is a distribution made for Ubuntu going back to 6.06 and up to 9.10 Karmic. All you have to do some cutting and pasting into the terminal to get it set up in Ubuntu. Pretty much..., the days of typing obscure commands into the terminal has long been over. Linux desktop is pretty much now point and click like Windows is.

UbuntuInstall ? GNU Radio

When I got more time I'll look into this further, I have several Linux machines (been dabbling in it for a couple of years). Looks more like another computer project for me down the road.


Linux.....

Without getting too off topic, Linux can be installed on your Windows machine either as a dual boot where the hard drive has Windows and Linux partitions. Or another method is to use a built in installer called WUBI , (like a program that can easily be installed or deleted with no permanent partitions). The best method I found is just to swap out hard drives and install Linux on the swapped out hard drive.

 

[1ADAM12]

Hardware might be a single RF DSP VLSI chip.

 

[yuccabrevifolia]

I love this kind of thing, though that site is pretty overwhelming for laymen like me. Wikipedia has a good description of the hardware end in simple terms. If you scroll down through the description to the daughterboards, that is where you can get a feel for the actual potential of the software/hardware combination. Universal Software Radio Peripheral - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Question_book-new.svg" class="image"><img alt="Question book-new.svg" src="http://upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png"@@AMEPARAM@@en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png

There is a paper on using these two pieces together to build a wireless TDMA setup between multiple computers. It does a pretty good job of showing a real application. http://academic.csuohio.edu/yuc/mobile09/avi.pdf

Definitely not a consumer level project yet (like a lot of the really cool stuff in Linux), but it is worth watching. I could see it making a good series of plug-ins for a Linux based receiver.

 

[meinename]

There's a reason for this being a solution looking for a problem.

GNU/Radio was written to prove that mandating a closed-source/access driver to a hardware tuner was NOT going to "prevent piracy, unlicenced transmissions" and other undesirable acts designated by BigContent through the FCC

GNU/Radio was to prove that radio tuning and transmission could be done in all software at the cost of CPU cycles. Trying to prevent users from direct access to hardware was useless and futile.

Since the GNU team already did the work, they left it published for anyone to use at a later time.

History:
This was written about the time of the fight to repeal the "Broadcast Flag of 2005"
Big-Content along with chipset manufactures were pushing locked-down, closed-source drivers to "protect" the recording of the transmission.

This would have killed all sorts of DVR/PVR software projects being written at the time. Any hobbyist-tinkering project would have been killed since the "Broadcast Flag" law stated that the radio must be protected from user modification.
There were 10 projects at the time, the most popular of them today being MythTV

GNU hates closed-source hardware drivers. You bought the hardware, you therefore have the right to modify it to suit your needs. The documentation should be available at a reasonable cost.
Reasonable being no more than what you paid for the original hardware/software.
If your new toy cost $100, another $100 (or less) will get you the documentation for your toy.

EDIT:

As for uses, pendragon covered the questions by our sponsors quite well.

Digging a little deeper, I found this repository for the code for some of the older projects.
https://cgran.org/wiki/Projects

I looked at this years ago and wanted to play with 802.11 (WiFi)
(Un)Fortunately 802.11g was finally cheap enough that I found this to be not worth buying.
Mind you at the time there was 3 schematics available for 3 broadband applications.
One could be used for 800MHz and below, 800MHz to 2400MHz, and finally 2400MHz and higher.

Now I want one.
A list of possible projects I want to try
Digital Shortwave (DAB)
D-ATV on L-band
DVB-S/S2 in both QPSK and 8PSK as well as 16QAM and 64QAM and the pre-release S2 turbo-coding.

Found the tuners!
http://www.ettus.com/order
This page has the tuners.
30 MHz, 54MHz-870MHz, 800MHz-2400MHz, 2.3GHz-2.9GHz (WiMax any one? see also: Clear/Clearwire Internet services) as well as a dual 2.4-2.5GHz and 4.9GHz-5.85GHz (WiFi/802.11 Dual-Band)

The 54MHz-870MHz allows for tuning TV, FM, VHF radio. I'll let some of you HAM's list some of the more interesting stuff there.

 

[Babadem]

Interesting topic. I will need to read more, to understand this topic.

 

[Cold Winter]

Ok, I am lost here. Say what?

SatelliteAV & Sadoun;


LOL, I think pendragon ( and a few others ) pretty much summarized it.

I'd be willing to bet if you showed it to a few of the engineers who supply you, they'd hit the roof either real excited or real ticked off.

If the excited ones can get you components, ( or as 1ADAM12 puts it a single VLSI chip, and various transceivers, that does the H/W functions ), you'd have a universal FTA-STB/ OTA TV/ AM-FM receiver... along with a lot of other things I won't get into here... all S/W controlled via your Home Theater PC.

Where else can you buy one piece of H/W ( or several identical units ) and effectively do everything wireless that there is?

.

 

[meinename]

made an addendum above.

 

[SatelliteAV]

Thanks for clarifying the applications. Certainly interesting concept.

So for only $1500 +/- you could have a satellite receiver that will work after you write the code and zero WAF? Cool!

Maybe be PCI-E or SATA hardware rather than be strangled by the USB cord?

 

[pedrogarcia]

So Brian I guess you aren't going to stock these

 

[SatelliteAV]

So Brian I guess you aren't going to stock these

Actually, it looks like an interesting project with an extremely very good profit margin!

Unlikely that a USRP unit could be a $100 item as originally suggested. Cost could be minimized if the board was simply cloned, sold with exchangeable or multi-tuner expansion and without technical support.

A major issue for distribution would be that it would be highly improbable to obtain Part 15 FCC approval for transmission for a wide spectrum device. Would the technology still be of interest if it were developed as a receive only project?

 

[classicsat]

One correction I'd like to make is that Digital Shortwave is not DAB, but Digital Radio Mondiale (AKA DRM). I am not sure of actual DAB, but DRM requires you license an audio codec or something, and apart form the Codec cost (very reasonable), much easier , hardware being home build able, if you have a decent SW receiver.

 

[cruzin]

I have Linux-Puppy on 3 pc's. !00 meg with good gui. Runs on old pc with very little ram.

 

[pedrogarcia]

Actually, it looks like an interesting project with an extremely very good profit margin!

Unlikely that a USRP unit could be a $100 item as originally suggested. Cost could be minimized if the board was simply cloned, sold with exchangeable or multi-tuner expansion and without technical support.

A major issue for distribution would be that it would be highly improbable to obtain Part 15 FCC approval for transmission for a wide spectrum device. Would the technology still be of interest if it were developed as a receive only project?

The current tech does not isolate receive only I think you are absolutely right, currently USRP cost is way too high for a project. To give tech support could well be a nightmare and you would certainly have the full attention of the FCC