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I'm trying to figure out how the mechanics of holographic radar work. AFAIK there is a continuous 3d transmission signal (a dome-shaped antenna?) But because there isn't a direction or time-domain, how do we observe the return signal from objects and locate them? Is there any reference material / books on how this works?

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It looks like any other modern signal processed multi-beam radar system - I think the "holographic" probably has more to do with their marketing dept than anything to do with holograms.

With phased array radars, instead of having a single rotating dish which transmits in a single direction and listens for a return form that direction, you have a series of fixed transmitters and receivers which broadcast and listen continuously. By measuring the the time a signal received at different receivers you can work out the angle it came from. In practice it's complicated, especially in environments with lots of background reflections - but with enough software it's doable.

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The important words here are "phased array" as in the post and "interferometry". –  dmckee Feb 10 '12 at 18:55
    
@dmckee, the term phased array has been used for a few different setups, I didn't want to be too specific of this device. But "Phased Array Radar" would be a good search term –  Martin Beckett Feb 10 '12 at 18:58
    
Ah very cool - I get it now. It turns out the original paper on ubiquitous radar was from Skolnik dtic.mil/cgi-bin/GetTRDoc?AD=ADA403877. The bit I was missing was that instead sweeping the transmitter phased array, the transmitter is omni-directional. The receiver 'beams' are swept electronically, therefore building up an 'interference' pattern (even though the receivers are not actually transmitting anything, they are sensitized to a direction). I'm guessing here that the transmitter still chirps? Or would we just handle the time domain slicing on the receiver side? –  velniukas Feb 11 '12 at 7:10
    
@velniukas - depending on the range you could either transmit individual 'pings' or a pseudo random continual signal (like GPS) and correlate the phase from that –  Martin Beckett Feb 11 '12 at 20:38
    
@MartinBeckett the continuous signal fits in with some of the reading I have been doing on ultra low power MRI's - which is exactly where I'm trying to go with this. Thanks again. –  velniukas Feb 20 '12 at 13:54

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