Bandwidth Analysis of Multiport Radio-Frequency Systems—Part II

We analyze the bandwidth over which power can be transferred from multiple radio-frequency sources to multiple loads through a passive multiport matching network. This is the second part of a two-part paper. In the first part, we introduce broadband multiport matching upper bounds and apply them to determine the bandwidth of loads and network structures whose scattering parameters can be expressed analytically with rational functions. In this second part, we apply the bounds to loads, such as antennas, whose scattering parameters are obtained by measurement or simulation. We focus on the effects of coupling on bandwidth. Since the bounds require frequency responses that are rational functions, we provide guidelines on how to obtain rational approximations for arbitrary loads. Complete derivations of the bounds are also provided.