Calculation of mutual antenna coupling within rectangular enclosures

We investigate the mutual coupling between dipole antennas that are enclosed by a rectangular, lossy cavity. The analysis is based on standard integral expressions for the mutual coupling that require the solution of coupled Halle´n´s or Pocklington´s equations within the cavity. Numerical solutions are obtained by the method of moments, and by taking advantage of an Ewald representation of the cavity´s Green´s function together with an interpolation scheme. The results exhibit the dominating influence of cavity resonances on the antenna coupling in the case of simultaneous coupling to a specific mode.