Factorization of Gaussian Coupling Efficiency and algorithm to compute it

Paper i proceeding, 2012

Gaussian Coupling Efficiency (η G) quantifies the amount of radiated power getting coupled to fundamental gaussian beam mode. This paper focus on the computations of η G for antennas from their far-field data. The mathematical analysis presented in the paper shows that the term η G can be factorized into sub-efficiencies namely, BOR 1, spill over, polarization and BOR 1 to Gaussian Coupling. This analysis is based on the definition of Body of Revolution type of antennas (BOR). Based on the analysis, an algorithm is developed to compute η G of Antennas. This algorithm accepts the far-field data of antenna as input and computes the optimum values of Beam Waist ω( o) and it's location (z o) for maximized η G. The algorithm is verified using Smooth Conical Horn. The beam parameters (ω o & z o) of Conical Horn obtained from near field measurements agree well with the beam parameters obtained from the simulated far-field. The 44 Microstrip patch Array is studied using this analysis and found that η G 70% is feasible for 320-350 GHz bandwidth.