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The following sketch shows a layout refinement which can be helpful in electromagnetic interference and electromagnetic pulse (EMI / EMP) protection of the components on a circuit board.
By avoiding the unwanted current loop's girdling of the entire circuit board, EMI / EMP transient couplings to loops that can include operational circuitry are much reduced.
Rail voltage foil paths can be arranged the same way for the same benefit.
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Having designed raised floor computer rooms, multi-layer PCB' and VHF/UHV/uWave antenna, I don't see the loop as real. It doesn't follow that a ground plane offers lower impedance on the perimeter at any wavelength. If you consider stripline impedances, the design you proposed may reduce copper consumption for ground plane but at higher impedance. Perhaps adequate, but less absorption of stray EMI. My 2 cents.
Posted by: Tony Stewart | November 11, 2011 at 11:35 PM
Oops yes I see you did show a loop, not a ground plane.
there are 2 schools of thought;
a) centralized ground
b) distributed ground
central ground or looped grounds earthed at convenient points to plumbing..may be adequate for most apps.
In either case for EMP or EMI nothing beats a double walled faraday cage but a ground plane antenna with the lowest impedance depends on wavelength and since EMP is broadband, tbe best ground is a ground plane A distributed T link ground plane you proposed looks like a Yagi Antenna with gain.
There is no simple answer. It depends on what EMI/EMP you want to block. But my bet is copper or cheaper...aluminum mosquito mesh faraday cage or at least a ground plane, earthed at many points.
Posted by: Tony Stewart | November 11, 2011 at 11:46 PM
Such a great and interesting post for me. Help me to give more better idea about it.
Posted by: pcb prototype | February 07, 2012 at 01:46 PM
This is interesting
Is there proof of concept that actually works.
For me I seen many different solution and proposal but limited actual hard proof.
Should the top end of copper be broken to avoid current path?
Posted by: riscy00 | February 23, 2015 at 06:16 AM