S/N Ratio Computation in Wire Antennas Using the Matrix Method

Abstract

Matrix Method has been extended to investigate S/N ratio at the output of a wire antenna treating it as N-port network. Computer results proved that the ratio of noise power spectral density delivered to a matched load by any antenna to K_oT is near unity, where K_o is the Boltzmann's constant. Expressions for cross-spectral densities between sub-elements of antenna obtained by the Fourier transform of cross-correlation function technique and from the ratio of mutual to self radiation influence co-efficients are found analytically identical in collinear, parallel and orthogonal positions. Computer results are presented in each case. The conditions for zero cross-spectral densities have been investigated. The effect on the S/N ratio of inductively loaded short linear dipole has also been studied by this technique.

Indexing terms:

• Wire antennas
• Matrix method