Electromagnetic Modal Analysis for the Wireless Channel between a Pair of Transmitter and Receiver

The transport process of the energy flowing in the wireless channel between a pair of transmitter and receiver is studied. The energy transport process is quantitatively governed by so-called energy transport theorem (ETT). In the ETT, there exists a source term—input power operator (IPO)—used to sustain the steady energy transport process. By diagonalizing the IPO, a set of fundamental modes propagating in the wireless channel are obtained, and the fundamental modes are energy-decoupled, so the fundamental modes are simply called energy-decoupled modes (DMs). This ETT-based diagonalizing IPO scheme provides an effective modal analysis method to the transmitter-channel-receiver structure. To avoid the risk that the core physical principle is covered by some complicated mathematical formulations, this paper restricts the transmitter to a relatively simple aperture-fed microstrip patch antenna, and restricts the receiver to a relatively simple aperture-loaded dielectric resonator antenna. In fact, the modal analysis method proposed in this paper can be easily extended to some more complicated transmitter-channel-receiver structures, such as metasurface-channel-metasurface structure.