A Wideband Low-Profile All-Metal Cavity Slot Antenna With Filtering Performance for Space-Borne SAR Applications

Abstract

This letter presents a wideband All-metal cavity slot antenna for space-borne SAR applications which achieves the filtering performance simultaneously. The proposed antenna consists of a metal cavity and several radiation slots. It was fabricated by aluminium through milling and welding process which is suitable for the space environment. Benefiting from multi resonances of the cavity and slots, the antenna obtains a wide bandwidth. An 8x12 antenna array is designed, fabricated and measured for verification. The measured impedance bandwidth of 51% from 7.2GHz to 12.2GHz for S11<-10dB is achieved. Furthermore, it shows good filtering performance of more than 20dB suppression level in the out-band comparing to the operating band which suppresses the unwanted interferences and contributes to the good EMC design. The cavity has a very low profile of 2.8mm, i.e. 0.067λ at the lowest operating frequency.

Filtering Antennas: Design Methods and Recent Developments

“…The most popular type of filtering antenna is based on a microstrip antenna (i.e., the filtering microstrip antenna or FMA) [13]- [29]. Other types of filtering antennas include filtering waveguide-slot antennas [30]- [35], filtering slot antennas [36]- [37], filtering dielectric resonator antennas (DRA) [38]- [41], and filtering dipole antennas [42]- [46]. The idea of filtering antennas has also been used in periodic structures design, such as metamaterial antennas and frequency selective surfaces (FSS) [47]- [49].…”

Application of Aperiodic 'Einstein' Monotile in Limited Field of View Phased Arrays

“…Commonly, for most large-scale phased arrays consisting of multiple subarrays, especially for air-borne or space-borne antennas where an all-metal antenna element is recommended [41]- [42], they need to be assembled with a load-bearing structure. However, Penrose tiling is fully unconditionally constructed, implying that every unit in Penrose tiling appears without a predictable order.…”

All-Metal 3-D Frequency-Selective Surface With Versatile Dual-Band Polarization Conversion

“…The concept underlying polarization conversion in a monolithic and all-metal 3-D structure could become a promising starting point for the development of low-loss external polarizers for operation in space or other harsh environments, where dielectric materials are avoided as much as possible. Many illustrative examples can be found in the literature justifying the interest in all-metal radiating structures (see for example [35]- [37] targeting at band X , L or K). These works reveal that, in addition to avoiding undesired electromagnetic phenomena (such as ESD or PIM), all-metal architectures allow to prevent the tolerances that are inherent to dielectric materials (mainly related to the permittivity).…”