Thu
20
Feb
Seminars and Conferences
Seminar - Degrees of Freedom and Shadow Area: Applications in Wireless Communication, Antennas, Imaging, Characteristic Mode
The number of degrees of freedom (NDoF) is a key metric across wireless communication, antennas, imaging, and computational techniques.
While NDoF can be numerically computed for regions with arbitrary shapes and diverse propagation environments, analytical approaches provide deeper insights into the underlying physical principles.
Prof. Mats Gustafsson from LUND University (Sweden) reviews the state of the art and introduces an analytical method for estimating the NDoF of arbitrarily shaped transmitter and receiver regions, expressed as the shadow area measured in wavelengths. These new expressions unify and extend established results, including those based on Weyl's law and the paraxial approximation. The analytical findings are validated by comparison with numerical evaluations of the singular values of the propagation channel in both free-space scenarios and more complex environments, such as ground planes and corners.
Furthermore, we explore connections to characteristic mode theory, imaging, and the compression of Method of Moments matrices, highlighting the broader implications of this approach.
While NDoF can be numerically computed for regions with arbitrary shapes and diverse propagation environments, analytical approaches provide deeper insights into the underlying physical principles.
Prof. Mats Gustafsson from LUND University (Sweden) reviews the state of the art and introduces an analytical method for estimating the NDoF of arbitrarily shaped transmitter and receiver regions, expressed as the shadow area measured in wavelengths. These new expressions unify and extend established results, including those based on Weyl's law and the paraxial approximation. The analytical findings are validated by comparison with numerical evaluations of the singular values of the propagation channel in both free-space scenarios and more complex environments, such as ground planes and corners.
Furthermore, we explore connections to characteristic mode theory, imaging, and the compression of Method of Moments matrices, highlighting the broader implications of this approach.