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According to the CWDP book, dipole antenna elements can be shortened by the square root of the dielectric constant used in the antennas cover (ie. its radome).

Does the same calculation apply to internal antenna "spacing" inside of a MIMO antenna package?

For example, if mounted externally one wavelength apart, the antennas might be spaced 4.84 inches apart.

So could they be spaced at 4.84/sqrt(2.0) = 4.84/1.41 = [b]3.46 inches[/b], if mutually covered in a plastic with a Dielectirc Constant of 2.0 ?

It appears the added capacitance is helping to "impedance match" the shortened antenna to keep it remaining at 50 ohms. Remember though, any time you physically shorten an antenna (via coils etc.) it will not perform as well. This means this shortened dipole antenna will actually have less than 2.14dbi gain. Next, physical separation is needed to "see" (potentially, not always) a different signal, and common sense says that is still at least one wavelength (regardless of antenna size, the wavelength at x frequency will be the same and that is what matters in antenna diversity (different than spatial streaming). This is how I understand it anyway --- Please someone chime in if I'm wrong here...

Daniel,

Sorry I didn't see your reply.  IE 8 no longer works correctly on the CWNP site, and I can't read the Forums main page at all.

That isn't the way I understand the shortening's effects.    Wouldn't shortening decrease the capacitance ?