Physical bounds on the antenna scattering matrix
Författare
Summary, in English
The antenna scattering matrix is based on a spherical vector wave expansion and contains a complete description of the matching, transmission, receiving, and scattering properties of an antenna. It is commonly utilized in near-field measurements and it can also be used to model MIMO antennas. Here, an approach based on the holomorphic properties of the antenna scattering matrix is used to derive physical bounds on the bandwidth of lossless antennas. The resulting bounds are expressed in the radius of the smallest circumscribing sphere and the polarizability dyadics of the antenna. The derivation and final results resemble both the classical work by Chu (1948) and a recently developed theory based on the forward scattering. However, instead of estimating the Q-factor through the stored energy, the low-frequency expansion of the scattering matrix is used to obtain a set of summation rules from which bounds on the bandwidth are derived. The use of Cauchy integrals and the low-frequency expansion in terms of the polarizability dyadics are similar with the approach in (Chu, 1948 and Gustafsson et al., 2007).
Publiceringsår
2008
Språk
Engelska
Sidor
4246-4249
Länkar
Dokumenttyp
Konferensbidrag
Ämne
- Electrical Engineering, Electronic Engineering, Information Engineering
Nyckelord
- sum rule
- spherical vector wave
- Physical bounds
- MIMO
Conference name
IEEE Antennas-and-Propagation-Society International Symposium, 2008
Conference date
2008-07-05 - 2008-07-11
Conference place
San Diego, CA, United States
Status
Published
Forskningsgrupp
- Electromagnetic theory