Environmental coupling loss effects in superconducting HF loop antenna design

Losses coupled into an electrically small HF loop receiving antenna system from its environment are investigated by analysis and computation using the NEC programme to assess the significance of such effects when superconducting technology is applied. Results are presented showing ground plane and terrain perturbations of the loop performance itself together with the effects of lossy supporting substrates and radiation screens on typical matching capacitors and coils. Q-factors of the order 10⁵ are feasible for these matching components, consistent with reasonable physical size but little can be done to offset the losses induced into the antenna itself. When put into perspective with the noise and bandwidth performance and other system parameters, it is evident that environmental coupling effects can be significant in the application of superconducting technology to electrically small HF loop receiving antenna systems. In conclusion the specific computed examples presented are critically examined and inferences stated