
BladeRF 2.0 micro - peter_d_sherman
https://www.nuand.com/bladerf-2-0-micro/
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dancek
> affordable for students and RF enthusiasts

Takes a lot of scrolling to see the price, which is $480. That's probably
affordable considering the specs. But the cheap way to experiment with an SDR
is to repurpose a $20 USB TV tuner.

~~~
acd
The cheapest way is to start with a RTL SDR tuner and for example Gnuradio.

If you want to experiment with celluar mobile radios LTE you need a LimeSDR,
BladeRF and a help processor.

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yasp
What is a help processor?

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acd
Help CPU I meant, something accelerating the signal processing from the
software defined radio often a FPGA, field programmable gate array.

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iwiririwo
In context of GnuRadio and similar, do any projects already utilize FPGA
acceleration as offered by USRP?

From what I've seen, it all happens on the CPU.

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ObscureMind
HackRF one can be purchased for $100 nowadays:
[https://www.aliexpress.com/item/HackRF-One-1MHz-to-6GHz-
SDR-...](https://www.aliexpress.com/item/HackRF-One-1MHz-to-6GHz-SDR-Platform-
Software-Defined-Radio-Development-
Board/32809842995.html?spm=2114.search0104.3.2.7f7e44bcnJRHLi&ws_ab_test=searchweb0_0,searchweb201602_3_10065_10130_10068_10890_10547_319_10546_317_10548_10545_10696_453_10084_454_10083_10618_10307_537_536_10059_10884_10887_100031_321_322_10103-10890,searchweb201603_51,ppcSwitch_0&algo_expid=15778239-d8e0-43f2-95ac-a3691a1b5c96-0&algo_pvid=15778239-d8e0-43f2-95ac-a3691a1b5c96)

Is it worth paying $380 more to have a better ADC and a few more bells and
whistles in the BladeRF micro?

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rhinoceraptor
IMO, the bladeRF is more of an alternative to USRPs, and the HackRF is more of
a hacker tool.

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jrockway
Not sure how impressed I am with the specs. It is nice that you can transmit
54MHz of bandwidth or whatever... but what can you do that's actually
interesting? It doesn't go down to HF where you can communicate around the
world. It doesn't have the oscillator stability to run WSPR in VHF. What do
people that transmit with this actually do that a $20 (or even $300 HT) FM
radio wouldn't?

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rhinoceraptor
There are ways of achieving lower frequencies with SDRs, for example the older
model of BladeRF has an expansion card that goes down to 60Khz.

There are tons of things you could transmit, for example GSM, DVB, ATSC, GPS,
amateur digital modes, the list goes on.

Voice/CW aren't really what SDRs are for, just like personal computers aren't
merely a replacement for typewriters. If all you want to do is voice/CW, then
yes, you should just buy a Kenwood or Yaesu. You _can_ do the same things with
an SDR, but that's not the point of them.

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ChuckMcM
Nice to have another MIMO radio in the mix.

When I first started experimenting with SDRs I thought "widest frequency
range" was the spec to go for, then it became "widest bandwidth" was the spec
to go for, and then it because "highest dynamic range" was the spec to go for.

The truth is, depending on what you're interested in, any or none of those
could be on your "must have" list.

My journey went as follows; first I wanted to see as many different signals as
possible from as many different sources as I could find. That suggested the
wider the frequency range the more success I would have. But those sources
transmit with a _modulation_ and that modulation might consume a little (CW)
or a lot (OFDM) of bandwidth. So more bandwidth, especially if something was
using multiple "channels" in a space became key. But what if you can't hear
what it is you are listening for? As digital devices the number of bits in
your ADC really impacts your ability to deal with large adjacent signals in
the band. You find yourself buying (or building) filters to knock back the US
FM band, or a nearby TV station for example. For doing some bluetooth work I
ended up with a band pass filter on the front end that killed off nearly
anything outside the 2.4Ghz ISM band.

Multiple inputs and outputs became a thing for me because I wanted to build an
LTE base station, so I backed the LimeSDR and got one of those. There are
interesting things to see when you have multiple receivers that are all
running from a phase coherent local oscillator. You get this for 'free' when
you have multiple receivers running off the same local oscillator.

Lower frequencies are their own problem, the physics gets in the way.
Fortunately it is well understood how to heterodyne DC to 200Mhz up into a
range that these SDRs will operate. Of course that teaches you about things
like phase noise and how it impacts your ability to separate individual
channels.

Lots of interesting things to learn, but it isn't just 'plug and go' with one
box that can see "DC to Daylight"[1]. Filters, to keep out the signals you
don't want. Amplifiers that bring up the signals you do want, and not too much
noise. Bandwidth to capture the full signal and a bit extra. Enough
sensitivity to pull out the modulation frequencies uniquely. And a fast enough
DSP platform to turn that mush into the actual signal you are looking for. It
is quite the pile of projects.

[1] Daylight being visible light RF signals :-) Radios that cover say 1MZ to
25Ghz can easily cost $100,000 so they aren't really the stuff you'll pick up
casually, but the industry is investing heavily and what you can do for as
little as $100 (ADALM-PLUTO) is pretty amazing.

~~~
twtw
Yeah, I've interacted with a lot of people that didn't appreciate the problems
of ridiculously high (2+ GHz) instaneous bandwidth. It sounds great and is
easy to sell, but the fact that a single high power signal can wreck
everything else is pretty problematic. At that point your options are: 1. Let
the high power signal drive the receiver rail to rail, and which point your
signals of interest are lost, 2. Set gain to avoid the highest power signal
causing clipping, at which point your signals of interest are again lost, this
time below the noise floor, or 3. Like you say, add a bunch of filters for the
high power undesirable signals, at which point massive bandwidth starts to
look less appealing.

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zokier
One unfortunate aspect of many of these new popular SDRs is that they do not
operate at lower frequencies, so you are going to miss all the HF/MF/LF fun,
and part of VHF spectrum. For example the 6 meter amateur radio band is not
directly accessible with this SDR.

I wonder what it would take to make a DC to VHF (300ish MHz) SDR to complement
these UHF SDRs

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Stratoscope
The original BladeRF has an optional transverter that gives you 60kHz to
300MHz. (I have one but haven't done anything with it yet.)

[https://www.nuand.com/product/hf-vhf-
transverter/](https://www.nuand.com/product/hf-vhf-transverter/)

I don't see one for the version 2 though.

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nezza-_-
Unfortunately the software support for the BladeRF 2.0 micro is not yet very
mature - the official installation instructions do not work (don't install
udev rules etc).

I would recommend waiting a couple of months and see how the ecosystem
develops.

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abledon
What board / software is the current leader in this space? Is there a brand
akin to Arduino ?

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rhinoceraptor
The HackRF ($300) or RTL-SDR ($20, but RX only) are the go-to hardware for
consumers/hackers. These devices are more limited than some of the newer SDRs,
but the software support is a lot better.

For software, the HackRF is probably the best ecosystem. It's open hardware,
and the firmware is GPLv2.

The software ecosystem for SDR is pretty messy, pretty much all of the
consumer/hacker SDR software is hard to set up correctly, and Linux only. The
easiest thing to use is the Pentoo distro, it has all of the common tools, up
to date and included in the base image.

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trdtaylor1
USRP radio was 2000$ plus daughter board cost for specific bands. The price of
this is so cheap; you can pop garages, car tire sensors, key fobs, cell phone
signals, all in one.

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zokier
With 61 MSPS sample rate, why they spec their filter to 54 MHz? Wouldn't that
cause aliasing?

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123919239
No it's the other way round; with 61 MSPS sampling rate, the theoretical
maximum bandwidth is 61 MHz, so they stay below.

[edit]

If you're missing the factor two, as in "sampling frequency must be twice the
maximum signal frequency", the keyword is complex sampling. With complex
signals, the sampling theorem is "sampling frequency must be greater than the
maximum signal frequency".

[edit2]

I don't want to make anybody read about sampling. So we have a real signal -
we're in the real world - and suddenly there's a complex signal? You basically
fork the signal, and delay one signal path by half the clock period. You can
then sample both signals at the same time, and collect the data you would get
when sampling with the double frequency. Because we sample two signals, we
store two samples at a time. One we call the real signal, one the imaginary --
and there we got our complex signal.

~~~
nickysielicki
For anyone wanting to read more, this article about IQ is very good:
[http://whiteboard.ping.se/SDR/IQ](http://whiteboard.ping.se/SDR/IQ)

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Praxish
Thanks for posting that. Very nice.

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imranq
Can this transmit more than 1Ghz of spectrum? I can’t see that from the
description

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dkrikun
Newbie question: what interesting applications does this technology have?

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rhinoceraptor
There's an infinite list of things you could do, for example:

\- wireless pentesting of GPS, RFID, NFC, garage doors, car remotes, etc.

\- Receive NOAA satellite weather imagery

\- Track airplanes using ASD-B

\- Amateur radio voice/morse code/digital modes

\- Run a GSM base station using OpenBTS

\- Capture every FM radio broadcast in your area, simultaneously

\- Transmit a DVB or ATSC stream to your TV

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exabrial
> 47MHz to 6GHz

Ok wow!

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twtw
By itself, that isn't particularly impressive - all that requires is a decent
LO + mixer. Make sure you aren't confusing frequency range with instantaneous
bandwidth.

