Is it possible to show only the ground planes like the one given in the figure?
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Electronic – How to show only Ground Plane in EAGLE
eaglepcb-design
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2) I highly recommend AGAINST cutting ground anywhere near high-speed signals. Stray capacitance really doesn't have too much of an effect on digital electronics. Usually stray capacitance kills you when it acts to create a parasitic filter at the input of an op amp.
In fact, it is highly recommended to run your high-speed signals directly overtop of an unbroken ground plane; this is called a "microstrip". The reason is that high frequency current follows the path of least inductance. With a ground plane, this path will be a mirror image of the signal trace. This minimizes the size of the loop, which in turn minimizes radiated EMI.
A very striking example of this can be seen on Dr. Howard Johnson's web site. See figures 8 and 9 for an example of high-frequency current taking the path of least inductance. (in case you didn't know, Dr. Johnson is an authority on signal integrity, author of the much lauded "High-Speed Digital Design: A Handbook of Black Magic")
It's important to note that any cuts in the ground plane underneath one of these high-speed digital signals will increase the size of the loop because the return current must take a detour around your cutout, which leads to increased emissions as well. You want a totally unbroken plane underneath all your digital signals. It's also important to note that the power plane is also a reference plane just like the ground plane, and from a high-frequency perspective these two planes are connected via bypass capacitors, so you can consider a high-frequency return current to "jump" planes near the caps.
3) If you have a good ground plane, there's pretty much no reason to use a guard trace. The exception would be the op amp I mentioned earlier, because you may have cut the ground plane underneath it. But you still need to worry about the parasitic capacitance of a guard trace. Once again, Dr. Johnson is here to help with pretty pictures.
4.1) I believe that multiple small vias will have better inductance properties since they are in parallel, versus one large via taking up approximately the same amount of space. Unfortunately I cannot remember what I read that led me to believe this. I think it's because inductance of a via is linearly inversely proportional to radius, but the area of the via is quadratically directly proportional to the radius. (source: Dr. Johnson again) Make the via radius 2x bigger, and it has half the inductance but takes up 4x as much area.
For a simple two-sided board, start by creating a ground polygon on the whole bottom layer. The trick then is to get Eagle to route most of the connections on the top layer. To do this, make the cost of routing within a polygon high and the via cost low. Actually you want to start with parameters more likely to find a solution, then tighten up the requirements over multiple optimization passes.
Before auto-routing, route the critical traces manually, and connect any grounds you can right at the pad to the ground layer. That will cause it not to waste routing space connecting the grounds.
Of course this all has to start with good layout that tries to put connected things near each other and oriented to have as few crossovers as possible.
After the auto-routing, you have to do some manual cleanup. The measure of a ground plane is how small the maximum dimension is of any island. Lots of small islands are better than a few big ones. This means you want the ground plane to flow around every via if possible. Unfortunately Eagle tends to clump vias, even with the hugging parameter set to 0. You can't set it negative, I tried. This means you have to see what the auto-router did and move things around a little to try to break up clumps of vias.
It's mostly about using the auto-router properly and realizing it's a tool, not a substitute for your own brain. If you are expecting fire and forget, you aren't going to get good boards.
Anyway, here is a auto-router control file from one of my 2 layer boards with the bottom layer a ground plane:
[Default] RoutingGrid = 4mil ; Trace Parameters: tpViaShape = Round ; Preferred Directions: PrefDir.1 = * PrefDir.2 = 0 PrefDir.3 = 0 PrefDir.4 = 0 PrefDir.5 = 0 PrefDir.6 = 0 PrefDir.7 = 0 PrefDir.8 = 0 PrefDir.9 = 0 PrefDir.10 = 0 PrefDir.11 = 0 PrefDir.12 = 0 PrefDir.13 = 0 PrefDir.14 = 0 PrefDir.15 = 0 PrefDir.16 = * Active = 1 ; Cost Factors: cfVia = 50 cfNonPref = 5 cfChangeDir = 2 cfOrthStep = 2 cfDiagStep = 3 cfExtdStep = 0 cfBonusStep = 1 cfMalusStep = 1 cfPadImpact = 4 cfSmdImpact = 4 cfBusImpact = 0 cfHugging = 3 cfAvoid = 4 cfPolygon = 10 cfBase.1 = 0 cfBase.2 = 1 cfBase.3 = 1 cfBase.4 = 1 cfBase.5 = 1 cfBase.6 = 1 cfBase.7 = 1 cfBase.8 = 1 cfBase.9 = 1 cfBase.10 = 1 cfBase.11 = 1 cfBase.12 = 1 cfBase.13 = 1 cfBase.14 = 1 cfBase.15 = 1 cfBase.16 = 5 ; Maximum Number of...: mnVias = 20 mnSegments = 9999 mnExtdSteps = 9999 mnRipupLevel = 50 mnRipupSteps = 300 mnRipupTotal = 500 [Follow-me] @Route Active = 1 cfVia = 8 cfBase.16 = 0 mnRipupLevel = 10 mnRipupSteps = 100 mnRipupTotal = 100 [Busses] @Route Active = 1 cfVia = 10 cfChangeDir = 5 cfBusImpact = 4 cfPolygon = 25 cfBase.16 = 10 mnVias = 0 mnRipupLevel = 10 mnRipupSteps = 100 mnRipupTotal = 100 [Route] @Default Active = 1 [Optimize1] @Route Active = 1 cfVia = 99 cfNonPref = 4 cfChangeDir = 4 cfExtdStep = 1 cfHugging = 1 cfPolygon = 30 cfBase.16 = 10 mnExtdSteps = 20 mnRipupLevel = 0 mnRipupSteps = 100 mnRipupTotal = 100 [Optimize2] @Optimize1 Active = 1 cfNonPref = 3 cfChangeDir = 3 cfBonusStep = 2 cfMalusStep = 2 cfPadImpact = 2 cfSmdImpact = 2 cfHugging = 0 cfPolygon = 40 mnExtdSteps = 15 [Optimize3] @Optimize2 Active = 1 cfVia = 80 cfNonPref = 2 cfChangeDir = 2 cfPadImpact = 0 cfSmdImpact = 0 cfPolygon = 50 mnExtdSteps = 10 [Optimize4] @Optimize3 Active = 1 cfVia = 60 cfNonPref = 1 cfPolygon = 60 cfBase.16 = 12 [Optimize5] @Optimize4 Active = 1 cfVia = 40 cfNonPref = 0 cfPolygon = 70 cfBase.16 = 14 mnExtdSteps = 5 [Optimize6] @Optimize5 Active = 1 cfVia = 20 cfBase.16 = 16 [Optimize7] @Optimize6 Active = 1 cfBase.16 = 18 [Optimize8] @Optimize7 Active = 1 cfBase.16 = 20
Best Answer
To my knowledge EAGLE displays signals and layers, thus if you click show onto the ground signal, it will also highlight areas with all vias, pads and other tracks (depends on what you mean saying "planes").
One trick comes to mind is to make things you want to see separately in another layer, but I am more than sure then EAGLE will have issues connecting layers reporting unnconnected areas and trying to place vias in unwanted places.
Thus I believe you can highlight specific signal, but can not hide all other signals from the layout unless they are in another layer.