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LimeSDR

limemicro.com

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Re: LimeSDR

#101

Post by the_only_law »

ohazi wrote: post #71

I wish them luck, but judging by the ~week I spent trying to get a LimeSDR mini to work, their product is so half baked that it's basically not fit for purpose, and if you're considering getting one, I'd recommend something with an Analog Devices front-end instead. The PLL would fail to lock at random frequencies and temperatures. You'd try to scroll through e.g. the 2.4 GHz ISM band and would randomly get downconver…

I bought me one a year or so ago with some big project plans that I just haven’t started. Sadly my math is not up to par for doing SDR work or Signal processing.

This is actually a shame. I looked into getting one of the cheaper USRP's (I think the cheapest options run a little more than the PCIe limesdr)

Re: LimeSDR

#102

Post by touisteur »

syedkarim wrote: post #91
touisteur wrote: post #61

Earlier quoted context omitted.

Oh thanks for your answer, that's very interesting! For someone wanting to upgrade from rtl-sdr that seems a good step up. While you're here, I'm particularly interested whether you're aiming for something more ambitious some day or 100% focused on kraken? I'm thinking coherent 32/64 rx channels or more? Also, is there a way to assemble two krakens and synchronize them somehow so as to have 10x coherent rx? :-) There…

We have plans to offer a few different versions of KrakenSDR. The entry level version will likely be the current version with 5 tuners. We are laying out an idea for 8 tuners, integrated CPU, and pre-set antennas; basically a turnkey system for remote operations. We can definitely produce more exotic beasts, but I don't think there is much of a market for a Kraken with a hundred heads.

Ah thanks. Yeah I was more going on the side of 'build your own phased array' and (I think) needed coherent receivers for that. 299usd is an amazing price for 5 channel rx. And, since the schematics and everything (?) is open, it might be a 1-semester EE end of studies project to extend it to 32 or more :-)

Thanks for taking time to answer my questions. This project looks amazing, can't wait HW availability.

Re: LimeSDR

#103

Post by the_only_law »

themulticaster wrote: post #95
ngz00 wrote: post #88

Any suggestions on where to start to use this as a LTE uplink that reads from an SD card and uploads images? I'd like to replace my expensive faulty game camera subscription.

In addition to what myself248 said: In case you aren't familiar with the details of consumer RF standards (including IEEE 802.11, but especially LTE or anything cellular related) or don't have some prior RF knowledge: To put it mildly, LTE is not an easy standard to implement on an SDR, especially if it's your contact with SDRs. Even GSM is nowhere near a simple stack. If you want to get a feeling for what kind of ce…

> If you want to get a feeling for what kind of cellular projects are possible using SDRs from a hobbyist/free software perspective, have a look at the Osmocom (Open Source Mobile Communications) projects

Just want to say these guys are absolutely awesome. I got a great hobbyist discount on some hardware from them for a project I’ve admittedly fallen behind on.

My only complaint was lack of documentation, but the source code of their stuff has been reasonable enough for me to read and get stuff working.

Re: LimeSDR

#104

Post by the_only_law »

amelius wrote: post #60
rfdave wrote: post #57

Earlier quoted context omitted.

WiFi is hard to support, it's very complex from a signal processing and timing perspective.

And probably also the protocol.

I mean you have to pay way to much money just to look at the specs (or settle for an older one that’s a pain in the ass to find for some reason)

Re: LimeSDR

#105

Post by ohazi »

mNovak wrote: post #99
ohazi wrote: post #92

Earlier quoted context omitted.

A B205. Mostly playing around with high spectral efficiency digital modulation techniques like PSK/QAM and OFDM using GNU Radio. Trying to shovel as much data as I can between two links with as little power as possible. I'd like to experiment with below-the-noise-floor communication, but haven't gotten there yet. It's sort of silly, because you can do all of this in simulation, but it's more fun with real hardware. E…

Wait, they're doing the exams online now? My laziness to go to a testing center has been holding me back this whole time

That's what I said... :-)

I used hamstudy.org and took a test administered by GLAARG over Zoom.

https://glaarg.org/

Re: LimeSDR

#106

Post by ytjohn »

mNovak wrote: post #99
ohazi wrote: post #92

Earlier quoted context omitted.

A B205. Mostly playing around with high spectral efficiency digital modulation techniques like PSK/QAM and OFDM using GNU Radio. Trying to shovel as much data as I can between two links with as little power as possible. I'd like to experiment with below-the-noise-floor communication, but haven't gotten there yet. It's sort of silly, because you can do all of this in simulation, but it's more fun with real hardware. E…

Wait, they're doing the exams online now? My laziness to go to a testing center has been holding me back this whole time

As mentioned, GLAARG and others does them online. However I'd like to throw out that amateur exams are held all over the place, quite often. These are typically friendly events and is a good way to meet people that have been in the hobby for a long time. Typically, your local VE team is part of a radio club that can tell get you lots of good getting started tips, especially if it pertains to local activity.

https://www.laurelvec.com/?pg=exams (All Laurel VE sessions are free and processed next business days)

http://www.arrl.org/find-an-amateur-radio-license-exam-sessi...

Re: LimeSDR

#107

Post by syedkarim »

touisteur wrote: post #102
syedkarim wrote: post #91

Earlier quoted context omitted.

We have plans to offer a few different versions of KrakenSDR. The entry level version will likely be the current version with 5 tuners. We are laying out an idea for 8 tuners, integrated CPU, and pre-set antennas; basically a turnkey system for remote operations. We can definitely produce more exotic beasts, but I don't think there is much of a market for a Kraken with a hundred heads.

Ah thanks. Yeah I was more going on the side of 'build your own phased array' and (I think) needed coherent receivers for that. 299usd is an amazing price for 5 channel rx. And, since the schematics and everything (?) is open, it might be a 1-semester EE end of studies project to extend it to 32 or more :-) Thanks for taking time to answer my questions. This project looks amazing, can't wait HW availability.

Although the direction-finding and passive radar software are both open source, the hardware is not (so no schematics, layout, BOM). Just wanted to clarify that for you and anyone else reading this thread.

Re: LimeSDR

#109

Post by threeio »

ohazi wrote: post #105
mNovak wrote: post #99

Earlier quoted context omitted.

Wait, they're doing the exams online now? My laziness to go to a testing center has been holding me back this whole time

That's what I said... :-) I used hamstudy.org and took a test administered by GLAARG over Zoom. https://glaarg.org/

Very much this... two good combos, although the laurel VEC is also fantastic.

Get your ticket, its a fantastic experimenters hobby... just ignore the stodgy old man part of it

Re: LimeSDR

#110

Post by rfdave »

easton_s wrote: post #98

https://www.drti.com/ https://web.archive.org/web/20161106083817/http://www.drti.c... The true master of SDR....

One of many Govt focused RF companies. Start from Watkins Johnson and look at the spinoffs, although they've mostly absorbed into Bigger defense contractors at this point Boeing bought DRT in '07?

This site has a good history http://blackradios.terryo.org/index.html

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