Novel Computational Method for Evaluation of the Effects of Random Rib Assemblage Errors on the Performance of Umbrella Antennas

Abstract

To reveal the effects of random rib assemblage errors caused by misalignment on the performance of umbrella antennas, a novel computational method is proposed to evaluate the effects of random rib assemblage errors on surface accuracy, and is further extended to assess the gain loss of electromagnetic performance. Based on the assumption of equilibrium equation of cable-nets and small amplitude deformation, the computational formula of surface accuracy with respect to random rib assemblage errors is derived. With the help of Ruze’s formula, the computational formula of gain loss with respect to random rib assemblage errors is obtained. Taking a typical umbrella antenna as a simulation example, the effects of random rib assemblage errors on antenna performance are investigated and verified by the Monte Carlo method. Simulation shows that the proposed method can predict the degradation of both structural and electromagnetic performance for umbrella antennas accurately with small amplitude deformation, and improve the computational efficiency with satisfactory accuracy, which will benefit the design of umbrella antennas.