7 ms·
BladeRF-wiphy: Open-source, software defined radio modem
- nimbius 6y agocongratulations to the team for the hard work and dedication to taking one step closer to a truly open source ap. but BladeRF is pushing...a thousand dollars...too rich for most :(
- the_only_law 6y agoMy very limited knowledge of SDR’s from when I was researching a project is that for a lot of use cases, the cheap ones just don’t have the bandwidth or frequency range. I ended up getting a limesdr which was enough to serve my needs, but it was still around $400 for the usb version.
- jacquesm 6y agohttps://www.nuand.com/product/bladerf-xa4/ https://www.nuand.com/product/bladerf-xa4/ $480 for the smallest. And while too rich for most is one way to look at it, another is that $1K would not even buy you a proper monitor all that long ago, and that this is a very low volume production. I think the price point is actually quite impressive, I expected it to cost substantially more, especially given the BOM, there are some pretty impressive bits on there, and those connectors and PCB are also not exactly free.
- invokestatic 6y agoI do not think wiphy runs on the xA4 because the FPGA is not powerful enough. So if you want to run this project, you'll need to shell out at least $720 for the xA9. I probably will.
- dang 6y agoIf curious see also 2018 https://news.ycombinator.com/item?id=18581271 https://news.ycombinator.com/item?id=18581271
- stagger87 6y agoImpressive project. Writing all the VHDL including the FFT and Viterbi decoder... I'm genuinely curious where the ROI on a project like comes from? Selling hardware and training materials? I'm assuming there must have been significant interest from customers, or maybe this is an ambitious employees side project? Can't wait to see a demo or some pictures of it running. Would love to see more details about the DSSS demod using the 20MHz rate, specifically regarding the correlation. Any references on this? (I'm a happy owner of the x115, been looking at the 2.0 for awhile now)
- csboyer 6y agoFor DSSS demod, my guess is a 20 tap match filter designed from a resampled RRC filtered barker sequence. Haven’t looked at the VHDL, but that’s how I’d do it.
- deleted 6y ago[deleted]
- ChuckMcM 6y agoOddly enough, some folks like doing this because of the dopamine hit of really understanding how something works. FWIW I'm that kind of person :-). But I certainly understand it isn't for everyone. The platform I've been using to explore stuff like this is an Ultra96 board with a LimeSDR as the receiver. The Ultra96 has the Zynq Ultrascale FPGA on it. Given that USB3 latency is < 10 uSec I am guessing (hoping?) I can implement it in the Ultrascale fabric which is fed IQ data from the USB 3.1 port.
- TaylorAlexander 6y agoHeh I’m that kind of person too. All my free time is spend building things!
- chris37879 6y agoYup, I love that feeling, I'm currently working on a software 3d renderer, I've always understood in principle how they work, but getting to actually implement one is really fun.
- chrissnell 6y agoI remember the hate that closed-source Winmodem got back in the 90s but software-defined modems can be far superior to hardware. Case in point: direwolf. I think it decodes APRS better than any hardware solution. https://github.com/wb2osz/direwolf https://github.com/wb2osz/direwolf
- vvanders 6y agoIf you like direwolf you might want to take a peek at the M17 project[1]. They're looking to do the same thing with what's happened with proprietary radio protocols and looks really promising: > M17 is a new digital radio protocol in development as an alternative to those currently available, with freedom in mind. Freedom in the code, protocol, voice codecs, and hardware. The goal is to provide a better option for digital radios in the future. [1] https://m17project.org/ https://m17project.org/
- wmf 6y agoWeirdly they keep saying 802.11 but apparently it's 802.11a/g.
- dfox 6y agoIt is somewhat natural to just refer to 802.X standards as 802.X when implementing them as that is the correct name of the standard and you need to read most of it in order to implement it. If you want to talk about distinct added features it makes sense to use the name of TG (ie. 802.[number][letter]) that drafted the specification of said feature, but it is mostly only an handy shorthand.
- axegon_ 6y agoVeeery impressive! Side note: By pure coincidence I spent 5-6 hours this weekend playing around with an sdr dongle and a raspberry pi (specifically sending images over fm). And I have to say, the ecosystem around sdr's is annoyingly poor on linux(unsure about other os-es but it does seem windows has it better).
- ronsor 6y agoI feel like it's easier to toy around on Windows, but if you want to do anything (and I mean anything) serious, you'll need Linux. That's been my experience anyway.
- minetest2048 6y agoIn my experience, most of the signal decoders are Windows only (WXtoIMG to decode NOAA satellite images and DSD+ to decode digital walkie talkie signals comes to mind) but for actual real time RF DSP work, most of it is done in GNU Radio, and its practically Linux only even if it can be installed on Windows. And we haven't talked about transmit yet
- codetrotter 6y ago> WXtoIMG Haven’t used it but found this from doing a web search https://wxtoimgrestored.xyz/downloads/ https://wxtoimgrestored.xyz/downloads/ which is available for not just Windows but also Linux and some older versions of MacOS X. It’s not open source and it’s not being updated but it might be worth checking out?
- ChuckMcM 6y agoNice. There goes another 3 weeks of my life :-).
- samstave 6y agoHow is it that an SDR is being praised for a $1K price-point, but I can buy an FM/AM radio for single-digit $ - yet I pay $1,000 for a cell phone today and it doesnt have a native FM/AM radio on it? People keep saying "just use data" - which is what I think to be a fn bullshit response. give me a device that has actual FM/AM capabilities natively. Seriously - the most high-tech wireless device in my pocket MUST include the *least* complex wifi capabilities which is over 100 years old by *DEFAULT* Assume you are out if signal range - there are FEW places out of FM/AM range...
- dfox 6y agoWhile receiving analog radio is trivial for the processing required, it is fairly low frequency transmission which requires antenna sizes which are not entirely practical for phone-like device. I would even assume that many phones contain the required hardware (which usually involve using headset cable as antenna) but don't have any kind of software support for it because of combination of minimal demand for such a feature and the fact that the entire experience is not exactly user friendly. Notably, Raspberry Pi uses wifi/BT radio which apparently either includes FM radio or used to in previous revisions (and apparently the radio chip is capable of receiving FM and directly sending the audio to BT headset, which is somewhat interesting feature given the usual requirement of wired headset as antenna).
- samstave 6y agoI figured it would come down to antennas.... but I am still disappointed...
- WrtCdEvrydy 6y agoAM/FM is really up to the handset manufacturer, some phones have the hardware turned off by the manufacturer.
- mjcohen 6y agoA number of phones, including my Samsung Galaxy S10e, have the built-in FM radio enabled. It needs to have a earphone plugged in, which it uses as the antenna. The app is NextRadio.
- Reventlov 6y agoRelated projects: - https://github.com/bastibl/gr-ieee802-11 https://github.com/bastibl/gr-ieee802-11 (gnuradio transceiver by the amazing Bastian Bloessl) - https://github.com/open-sdr/openwifi https://github.com/open-sdr/openwifi (efforts to make a low-cost SDR Wi-Fi transceiver) From my point of view, cool projects, all the hardware I have access to is closed source and sometimes I really wish I could just change some low level parameters in my Wi-Fi cards.
- wrycoder 6y agoBut are you willing to part with $720 to play with it?
- concernedctzn 6y agoWow, this looks like a very powerful tool. Always wondered what a fully open wifi stack would look like
- jcims 6y agoCurious if anyone will use this to more capably fuzz the 802.11 stack in commodity equipment.
- PIKAL 6y agoSpeaking of radios, I’ve been trying to understand light recently and it’s difficult. I find that for most things, I have a visual intuitive model to reason about things. But I have a hard time visualizing RF light. There aren’t any good videos out there of just a straight forward visualization of RF light. It’s all abstractions with a sine wave, but no visceral visualizations, rendered or otherwise. The closest thing I’ve found is thought emporium visualizing wifi. And also, why can visible light pass through other visible light without causing interference? Why can’t they make visible light with an antenna? Why are large arrays of RF receivers not more widely used for small-scale RF imaging?
- duckfang 6y ago> But I have a hard time visualizing RF light. The best things I can recommend is to play with GnuRadio, IQ data, false color representation of a freq or set of frequencies bound to color/decibel strength, and ParaView and importing said IQ data for graphing. Think of the frequency of light as its color, and dB strength of how bright it is. However at cm and m wavelengths, voids happen much more regularly. That light can 'bend' around, and go through objects. > There aren’t any good videos out there of just a straight forward visualization of RF light. There's quite a few false color images. If you look at hydrogen line radioastrometry, there's a ton of false color images. There's also this HackADay that mapped wifi for a wide area covered by their CNC gantry https://hackaday.com/2015/02/17/mapping-wifi-signals-in-3-dimensions/ https://hackaday.com/2015/02/17/mapping-wifi-signals-in-3-di... > And also, why can visible light pass through other visible light without causing interference? EM primarily only directly affect things with an electric charge. EM radiation itself doesn't have an electric charge, therefore EM usually doesn't affect other EM. However, if we include gamma (+10^19 Hz), then if those collide, they can create an electron and a positron. But that's only theorized with energy vector diagrams and not actually seen. > Why can’t they make visible light with an antenna? You can... You just have to pump enough energy in it to make it glow! /hahaha > Why are large arrays of RF receivers not more widely used for small-scale RF imaging? That's primarily a cost issue. Go look how much a single RF frontend chip and an a/d chip costs. (Price gets to stupid levels at, say 24 bit A/D). Now instead, lets look at human vision. Humans can see (eyes are receptors of radio from 380nM to 720nM). When converted to Hz, we're talking 372.55 THz wide spectrum vision. My SDR on the table can see 112 MHz, or .0000112 THz Now, in order to replicate what's going on in the eye, you'd need millions of antennas AND data acquisition (of some sort). And then, even with current SDRs, these generate 60GB/min - you need the disk, memory, and CPU to do stuff with that. It's NOT a trivial problem. Now there are some RF arrays out there. KerberosSDR is one such array. However, its max bandwidth is 3 MHz @ 8 bit. And it can only do 4 inputs, which is enough to do geographical tracking of radio signals (within 24MHz to 1.7GHz). I know of one person who's trying to do some VR work with a KerberosSDR. The other problem, once you have the millions of antennas and data acquisition, is a matter of synchronization. Timing is also another stupidly hard area, which increases geometrically with more sensors. And remember that 1nS = 11.8 inches deviation.. So whatever processing you're doing had better be time consistent and local to the device. Eventually, we'll get to what you're proposing. A lot of us are wanting that. But we're decades away.
- qwerty__ 6y agoHey lazy question, so if you buy this and program it is it already FCC / CE certified for say 802.11a? And could you sell it like how companies sell RPis pre-packaged up with some software?
- deleted 6y ago[deleted]
- R0b0t1 6y agoThis is a guess, but it is a good one: no. It may not even be possible to get it certified (wrong interpretation of the law to me, but the government has more lawyers than anybody else). Many SDR boards don't have the power required to do actual transmission as it is hard to design a front end that pleases everyone, but equally as important, any real transmit power could mean the device is construed as non test equipment. Why do you care? Just buy it and flash the bitstream to it, no one will ever find out.
- TaylorAlexander 6y agoIt would matter to anyone who might want to build it in to a product.
- bradfa 6y agoThis would be a horrible way to make a product which isn't a piece of test equipment. The power consumption and manufacturing cost is orders of magnitude higher than a specific purpose device.
- TaylorAlexander 6y agoI maintain that the original question was valid and it’s up to the product designer to determine whether the trade offs are worth it. I mentioned it because I am designing a farming robot where a very reliable Wifi device might be worth the cost and power consumption. I don’t know if this product is “very reliable” but lots of Wifi isn’t. I’m already considering that exact software defined radio for our robot so it could actually represent cost savings if it replaced the Wifi adapter. Moreover I disliked the tone of the reply “why would you need to know the answer to your question, just do it and no one will notice.” It was a perfectly fine question to ask and I find it unreasonable to suggest it wasn’t worth asking without getting more information from the person asking it.
- deleted 6y ago[deleted]
- mediocreguy 6y agoWhat app are they using for the amplitude-v-time plots?
- casylum 6y agoLooks like modelsim https://github.com/Nuand/bladeRF-wiphy/blob/main/fpga/modelsim/wlan.do https://github.com/Nuand/bladeRF-wiphy/blob/main/fpga/models... https://www.mentor.com/products/fv/modelsim/ https://www.mentor.com/products/fv/modelsim/
- cushychicken 6y agoThis is one of the best single-page descriptions of wifi implementation at the packet and Linux kernel level I've ever seen. Very good.
- teleforce 6y agoNice one Nuand, the BladeRF v2 looks like a very interesting alternative SDR modem to the cheaper Adalm Pluto educational kit by Analog Devices, the manufacturer of the transceiver chip being used by the BladeRF v2. There is another alternative open source WiFi stack, openwifi and it has been discussed in HN before [2][3]. [1]https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/adalm-pluto.html https://www.analog.com/en/design-center/evaluation-hardware-... [2 ]https://github.com/open-sdr/openwifi https://github.com/open-sdr/openwifi [3]https://news.ycombinator.com/item?id=24273919 https://news.ycombinator.com/item?id=24273919