Re: [Discuss-gnuradio] [GSoC2018] Adding Passive radar and multiple device support to gr-radar toolbox

[Benny Alexandar]

Hi Suraj,

I would like to know for measuring the reference signal how do you determine the direction of transmitter ?  In case of WiFi which direction you set your antenna for making it as reference ?

-ben

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From: Discuss-gnuradio <discuss-gnuradio-bounces+address@hidden> on behalf of suraj hanchinal <address@hidden>
Sent: Sunday, March 25, 2018 7:36 PM
To: jmfriedt
Cc: address@hidden; address@hidden
Subject: Re: [Discuss-gnuradio] [GSoC2018] Adding Passive radar and multiple device support to gr-radar toolbox

 

Hello everyone, 

After reading the suggestions as well as feedback from Marcus Muller and Martin Braun, I have made the suggested changes as well as explained the algorithms in greater detail. Please read the updated proposal and provide feedback and suggestions.

Thanking you,

Regards,

Suraj Hanchinal

GSoC Proposal: https://github.com/surajhanchinal/GSoC_proposal/blob/master/My%20GSoC%20Proposal.pdf

On Sun, Mar 25, 2018, 2:18 PM suraj hanchinal <address@hidden> wrote:

Hello Jean-Michel Friedt,

Thank you for your valuable feedback. That is a very good insight since I overlooked the cross-ambiguity function and its calculation considering them trivial. I will definitely look into the papers that you mentioned and include them in my proposal. 

Thank you,

Regards,

Suraj Hanchinal

On Sun, Mar 25, 2018 at 2:12 PM, jmfriedt <address@hidden> wrote:

> All in all, this is pretty ambitious, but exciting!
> How will you tackle the OFDM signal recovery? I think your reference
> [2] is really much to be completely done in one GSoC, so it would be
> totally OK to say you just picked a reduced approach. Still, if you
> want to do that in all its glory, that would be cool, too, but I'd ask
> Martin how much work he'd expect that to be, and if necessary, reserve
> more time for the algorithmic part alone. I'm also including Jean-
> Michel Friedt of low-cost passive radar fame[A], as I hope he might
> have a moment to read and comment on your proposal.

I am not sure I can provide useful comments on the proposal, whose
various iterations I have been reading as they were being updated. Real
time passive radar processing seems challenging to me, and I would
advise looking at alternatives to the brute force cross correlation of
the Doppler shifted signal. You might want to have a look at
https://www.researchgate.net/publication/279069212_Batches_algorithm_for_passive_radar_A_theoretical_analysis
and especially its Table I which lists computational complexity of
various algorithms. An updated version of the document cited by Marcus
is at http://jmfriedt.free.fr/dvbt_hardware.pdf (submitted for
publication but not yet accepted): beyond the improved batches
algorithm allowing for much faster computation, we also address using
multiple receivers in parallel, each tuned to different carrier
frequencies.

JM

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JM Friedt, FEMTO-ST Time & Frequency/SENSeOR, 26 rue de l'Epitaphe,
25000 Besancon, Fr Michaelance