Metal Space Frame Radome Research Articles

Integrated optimum design of metal space frame radomes with variable size members involving electromagnetic and structural analysis

The presence of a metal space frame (MSF) radome inevitably degrades the electromagnetic (EM) performance of the enclosed antenna, while the deformation of the radome can worsen the degradations. In this study, with the introduction of the concept of variable size member, a multidisciplinary optimisation model is proposed to implement the sizing optimisation for the members of MSF radomes to improve simultaneously the EM performance, structural performance, and self-weight simultaneously where EM analysis and structural analysis are involved. Furthermore, a method is presented to boost the efficiency of the EM performance analysis, which makes possible the optimisation of electrically large MSF radomes. A 70 m MSF radome is simulated, and the results indicate that the proposed radome design with variable size members is superior to the conventional radome design with constant size members in terms of all the optimisation objectives, especially the EM performance and self-weight. Several conclusions with guidance values are drawn based on the results.

A Novel Compensation Strategy for the Radiation Characteristics of Large Dielectric Radomes Based on Phase Modification

To mitigate the degradation of radiation characteristics for large ground-reflector antennas due to dielectric radomes, a simple compensation strategy based on phase modification has been proposed. A modification of the phase distribution in the original aperture of an enclosed reflector antenna via moving the feed or subreflector along axial direction opportunely could compensate the phase shift caused by dielectric radome, minimize the phase difference in transmission aperture, and reduce the distortion of the antenna’s far-field pattern. The movement of the subreflector could be calculated by a formula, which has been provided in this work based on geometrical optics (GO). Good compensated results are obtained in a 9.14-m one-piece dielectric sandwich radome. The proposed compensation strategy could also be applied to metal-space frame radome; a 20-m radome is presented to verify the results .

EM Analysis of Deformed Metal Space Frame Radome

The presence of radome inevitably degrades the electromagnetic (EM) performance of the enclosed antenna while the deformation of the radome may make the degradations even worse. This letter studies the effect of structural deformation of a metal space frame (MSF) radome on EM performance. Far field of the antenna-radome system is obtained by adding the far field transmitted through skin to the scattered field of elements, both fields varying when deformation occurs. A 20-m MSF radome is employed for simulation, whose structural deformation under wind and self-weight is analyzed using finite element method (FEM). Several significative characteristics about the effect of deformation on EM performance are pointed out.

Depolarization properties of metal space frame radomes for use in satellite communication systems

AbstractRadomes have traditionally only been used in military satellite systems. However, higher availability civil applications are demanding their consideration in the higher frequency bands and for dualpolarization frequency re‐use systems. This paper investigates the depolarization performance of metal space frame radomes and presents results of XPD for radome covered antennas in the 4/6 and 11/14 GHz bands and for antennas of 30, 11, 5 and 3 m diameters. It is demonstrated that current polarization specifications adopted in the INTELSAT system should be able to be met by radome covered earth‐stations using conventional antennas.

Electrical design of metal space frame radomes

Formulation and results are presented of a digital computer program, which analyzes the electrical effects of a metal space frame radome, using a single scattering approximation. Under the assumption of uniform or nearly uniform distribution of space frame elements over the surface of the radome, simple approximate formulas are presented for the same effects. Computed values agree well with measured data. The effects of shaping the element cross section, varying the radome geometry, and varying the frequency have been systematically studied in certain cases. The results are presented here as applications of the theory. The effects of multiple scattering have been measured and also analyzed by an approximate theory so that they are fairly well understood. Formulas for the effects of radome tolerances on electrical performance are given.