Video stream reception


can we able to receive some video transmission, will be some drivers / app ?
I think on drone, with downconverters or ATV (amateur TV transmission)

A lot of old or existing global TV standards have been partially of fully implemented in Gnuradio either TX, RX or both. Adapting the existing code to work with a LimeSDR should not be difficult. There may be legal problems (license fees payment for use of patents) using some protocols.

DVB-T2 -
DVB-S2 and DVB-S2X -

As for drones I think a lot of those use proprietary video protocols, that you may need to individually backward engineering and write your own encoder/decoder blocks.

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Thank you for reply and info, I wait the board and see then :slightly_smiling:

Most drones use simple 5.8 GHz PAL video transmitter. So it is really simple to decode, the problem is that LimeSDR doesn’t have needed range (only 3.8 GHz max.). But there is possibility to downconvert 5.8 GHz into LimeSDR range, see this thread: Downconverter (and possibly upconverter) for 5.8 GHz band

A down converter might be a “jump too soon” …
If the low or bandpass filter is changed to pass 6ghz … i think you could operate on the 3rd harmonic.
As long as the signal generator produces a good square wave and not a clean sign wave …

I do with with a UHFSDR that has a top end of 707Mhz … its signal source is from a Si570 and is a nice square wave … just like expected, 3rd harmonic operation has less signal …

OK … this should work …
I read that the 3rd harmonic of a square wave is 180Deg from the fundamental … that means that the image will reverse …

I verified this with my UHFSDR that is also a I/Q sdr using a squarewave LO.

It had me confused at first because when i changed the freq of the Lo down or up … my sdr software would not track correctly … untill i read the formentioned fact about the phase of a 3rd harmonic (thank you Sony corp for the work on Wifi I/Q generation on a harmonic of a square wave and making the findings public) …

As far as i could tell – on HF and VHF (146.88mhz) the error of amplitude/phase does not change hardly at all – i couldnt see a change – besides the 180deg reversal. Makes sense because the amplitude/phase error is a function of hardware … not signal generation or software (well … once calibrated its not)

Personal y im not sure why LimeSDR is using filters on the RF lines to the mixers (between the mixers and I/Q signal coupling – the transformer) … It creates I/Q phase/amplitude imbalance due to components that are not 100% the same … differences in resistance, inductance and capacitance will manifest amplitude/phase errors that change based on freq. Eliminating them from between the combining transformer and mixers and placing the filter between the combining transformer and antenna jack would be a better place … i would think.

Anyways … im just saying that it should work … IF IF IF … don’t you just hate “IF’s” – i don’t like unknowns … at least this kind.

Oh forgot to mention (almost) that the operating on the 3rd harmonic dropped the signal by 10db …