**6.1. Capacity analysis**

The capacity for the averaged synthesized patterns according to the number of sampling antennas across the ECC (Electronic Communications Committee) standard's UWB band was analyzed using (26). The term *pi* is taken from the power spectral density levels of the ECC UWB spectral mask, *λ<sup>i</sup>* is the Eigenvalue of the subchannel from the matrix **S** and *σ*2 noise = *kTB*, where *k* is the Boltzmann constant, *T* = 297 K and *B* = 100 MHz. Fig. 6 shows the capacity of the synthesized radiation pattern using 2×2×2 till 5×5×5 sampling antenna elements within the defined 5×5×5 cm3 physical space. It can be seen that the higher the number of sampling antennas, the more the capacity increases, agreeing with the theory in [18]. Noting that the rise in the capacity is decreasing with the higher element configuration used, we conclude that the 5×5×5 configuration is nearing the capacity saturation limit.
