The real space consumption depends on the design of the device. In the doublesided case, it is quite difficult to reduce the height to less than 2.0 mm with good antenna performance. These examples should illustrate that the antenna space requirement can hardly be defined. It depends on the particular device, its design and other components. Testing The main test for an antenna is the S11 parameter test.
High values indicate that the electromagnetic wave gets reflected.
Although this test only shows the bandwidth of the return loss, skilled test personnel might be able to estimate the radiation performance to a certain degree. As regards gain tests, several different measurement technologies currently exist. The classic test method uses an unechoic environment. This enables the operator to see in which direction the antenna radiates and in which polarization. But usually, the total antenna efficiency is more interesting than the exact radiation diagram.