Fourier Optics Based Analysis of Focal Plane Array of Distributed Absorbers

Activity: Talk or presentationTalk or presentation at a conference

Description

Large format arrays of direct detectors are being used in the development of passive imaging cameras at sub-millimeter wavelengths. Several of these arrays are being developed with bare absorbing meshes without any antenna coupling (lens or horn) structures. The design of such arrays is typically done by resorting to geometrical considerations or basic broadside plane wave incidence analysis. This paper presents a spectral analysis technique of such focal plane arrays based on Fourier Optics. The analysis constitutes a step improvement with respect to previously used methods by providing an accurate and efficient way to estimate the point source angular response and the throughput from a distributed incoherent source of an absorbing mesh in the focal plane of a quasi-optical component (e.g. a parabolic reflector or lens). The proposed technique is validated with full-wave simulations. Moreover, the paper compares the performance of arrays of bare absorbers in the focal plane of a quasi-optical component to those of corresponding antenna based arrays. It is found that absorbers lead to a comparable trade-off, in terms of spill-over and focusing efficiency, only for very tight samplings.
Period9 Apr 2018
Event titleEuCAP 2018: 12th European Conference on Antennas and Propagation
Event typeConference
Conference number12
LocationLondon, United Kingdom
Degree of RecognitionInternational