What's the correlation between spectral graphs produced using near field probes and ones produced using an antenna?
How far can you go using just near-field probes?


Near field probes that I know of measure one-half of the emitted EM radiation - they are usually inductive loops that just pick-up on the magnetic part of the radiation. As the name suggests they are near field probes and, in the near field to a potential radiator, a full EM wave has not formed so it is correct that a near field probe only measures either the electric or magnetic field strength.

At some distance from the "radiator" (usually about one wavelength and greater), the E and H fields can combine to form a proper EM wave but, this cannot be determined by near field measurements because some "potential radiators" produce near field signals but are very poor at being a far-field antenna - luckily, these don't pose a problem but, you can't really tell that with near field probes.

In answer to your question I'd say "no".

Home-brewed equipment with a reasonable antenna can give quite decent results especially if you have previously "calibrated" results with "test-house" results.