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Homemade 6 GHz pulse compression radar

hforsten.com

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Re: Homemade 6 GHz pulse compression radar

#11

Post by user_7832 »

itishappy wrote: post #9
vlovich123 wrote: post #3

Could this be adapted into a voxel system? Seems like it could be cheaper than LIDAR which are a huge cost for why the HW for self-driving systems are so expensive & work in far more environments that LIDARs struggle with. I suspect getting multiple directions simultaneously is hard?

Not without significantly complicating your antenna setup (and the data processing setup too). You guessed it, getting multiple directions simultaneously is hard. Note how the current system only detects distance and speed in 1 dimension. Here's an analysis from someone smarter than me: > To enable the new features, radar systems now use multiple input/multiple output (MIMO) antenna arrays for high-resolution mapping…

So would this mean that with a few more transmitting and receiving antennas it could have comparable resolution to lidar?

Re: Homemade 6 GHz pulse compression radar

#12

Post by spitfire »

throwup238 wrote: post #2

This is great. It’s the last piece I needed for my suburban missile guidance system! This will be the last year the Joneses survive the annual block party. Can you do phased array radars next? I need the extra precision. There’s a few neighbors who don’t clean up after their dogs…

These should help.

Tactical and Strategic Missile Guidance, Seventh Edition https://www.amazon.com/Tactical-Strategic-Missile-Guidance-S...

Tactical missile warheads https://www.amazon.com/Tactical-Warheads-Progress-Astronauti...

Re: Homemade 6 GHz pulse compression radar

#14

Post by nick__m »

Why the ground planes are on layer 2 and 6 instead of 1 and 6 ?

Naively, as someone who doesn't have high frequency PCB design experience, I would have placed my grounds to form a shield and put my voltage plane on layer 3 or 4. I am sure that there is a good reason behind that choice but I don't see it.

Re: Homemade 6 GHz pulse compression radar

#15

Post by auspiv »

Incredible work. Crazy that this could be done by a single person. Stick it on a rotating pedestal and you've got a planar radar detector. Add some tilt and then it's not much different than aircraft/weather radar I suppose.

The cost (in $LOCAL_CURRENCY, or $570 according to another comment) isn't great but I can only imagine how many hours this took.

Given a proper budget, the sky is the limit.

Anyone know how .mil aircraft would interpret being tracked by a 6 GHz radar build by a civilian(yes I am aware that his estimated max distance is 1200m, assume he increased that by a factor of 10 with larger antennas or something)?

Re: Homemade 6 GHz pulse compression radar

#16

Post by [deleted] »

throwup238 wrote: post #2

This is great. It’s the last piece I needed for my suburban missile guidance system! This will be the last year the Joneses survive the annual block party. Can you do phased array radars next? I need the extra precision. There’s a few neighbors who don’t clean up after their dogs…

[deleted]

Re: Homemade 6 GHz pulse compression radar

#17

Post by _Microft »

nick__m wrote: post #14

Why the ground planes are on layer 2 and 6 instead of 1 and 6 ? Naively, as someone who doesn't have high frequency PCB design experience, I would have placed my grounds to form a shield and put my voltage plane on layer 3 or 4. I am sure that there is a good reason behind that choice but I don't see it.

> Above is the final DDR3 routing on all the PCB layers. Layers 2 and 6 are ground, 5 is supply voltage, and others are reserved for signals. Two grounds are needed for correct impedances on the top, middle, and bottom traces of the PCB. With only one ground plane, the distance from the signal to ground would be too large on either the top or bottom layer.

Is the textual description in the article correct? To me the images make it look like signals are on 1 (red), 3 (orange) and 6 (blue), with ground on 2 (green) and 5 (pink) and supply voltage on 4 (teal). If you match some vias, you will find that 2 and 5 are definitely connected.

Re: Homemade 6 GHz pulse compression radar

#19

Post by [deleted] »

spitfire wrote: post #12
throwup238 wrote: post #2

This is great. It’s the last piece I needed for my suburban missile guidance system! This will be the last year the Joneses survive the annual block party. Can you do phased array radars next? I need the extra precision. There’s a few neighbors who don’t clean up after their dogs…

These should help. Tactical and Strategic Missile Guidance, Seventh Edition https://www.amazon.com/Tactical-Strategic-Missile-Guidance-S... Tactical missile warheads https://www.amazon.com/Tactical-Warheads-Progress-Astronauti...

[deleted]

Re: Homemade 6 GHz pulse compression radar

#20

Post by nick__m »

_Microft wrote: post #17
nick__m wrote: post #14

Why the ground planes are on layer 2 and 6 instead of 1 and 6 ? Naively, as someone who doesn't have high frequency PCB design experience, I would have placed my grounds to form a shield and put my voltage plane on layer 3 or 4. I am sure that there is a good reason behind that choice but I don't see it.

> Above is the final DDR3 routing on all the PCB layers. Layers 2 and 6 are ground, 5 is supply voltage, and others are reserved for signals. Two grounds are needed for correct impedances on the top, middle, and bottom traces of the PCB. With only one ground plane, the distance from the signal to ground would be too large on either the top or bottom layer. Is the textual description in the article correct? To me the…

thanks, layer 2 and 5 would fit the rest of the description and the reason would then be in the text :

  Two grounds are needed for correct impedances on the top, middle, and bottom traces of the PCB
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