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In this paper, flexible and deployable double-sided linear-to-circular polarizers designed on polydimethylsiloxane are proposed for the first time to the best of our knowledge. ShieldIt textile is used as the conducting element of the two designs based on two different unit cell arrays: a loaded circular patch unit cell or an unloaded circular patch unit cell, both backed by a generic rectangular element on its reverse side. This is in contrast to conventional frequency-selective structure-based linear-to-circular polarizers implemented using rigid substrates, which are multi-layered and requires inter-layer physical spacing. This complicates their implementation using flexible substrates and in a deployable format. Upon implementation of this double-sided polarizer, their final performances are evaluated in terms of the phase difference, conversion efficiency, 3-dB axial ratio (AR), and ellipticity bandwidth (from 40 • to 45 •). Measurements indicated good agreements with simulations, and both structures exhibited more than 90% of conversion efficiency from 2.34 to 3 GHz (for the loaded circular unit cell) and from 2.36 to 3 GHz (for the unloaded circular unit cell). In terms of ellipticity, a bandwidth of 8.67% is observed for the unloaded design and 13.82% for the loaded design. The unloaded structure exhibited a fractional 3-dB AR bandwidth of 36.36% (from 1.98 to 2.86 GHz) in simulations, and 32.64 % (from 2.00 to 2.78 GHz) when evaluated experimentally. Conversely, the loaded design showed only 12.58%. An equivalent circuit model is proposed and validated via a comparison between the circuit and full-wave simulations. Finally, the performances of these polarizers are also assessed under different bending conditions due to the use of flexible materials, prior to the proposal of a suitable deployment mechanism.

A new swastika‐shaped single layered flexible linear‐to‐circular polarizer is proposed for Cube Satellite application in S‐band. The proposed linear‐to‐circular polarizer is designed fully using ShieldIt Super conductive textile on a lightweight felt substrate. Principle of operation is discussed comprehensively with an equivalent circuit model and its interaction with different orthogonal polarized wave components along with a succinct study of surface currents in different polarizations. Another linear‐to‐circular polarizer implemented on Polydimethylsiloxane (PDMS) substrate is designed and compared with the textile‐based design. A preliminary deployment scheme is also proposed and studied by analyzing its performance under different bending conditions. Both textile and PDMS structures are confirmed to be operational within the range of 2.39 to 2.45 GHz. The textile polarizer is then prototyped and validated to be exhibiting similar conversion efficiency (CE) of 98% (simulated) and 93% (measured) at 2.45 GHz. Moreover, the fractional bandwidth defined by their 90% CE limits are 7.35% (from 2.36 to 2.55 GHz) in simulations and 6.6% (from 2.36 to 2.52 GHz) in measurements. The resulting axial ratio produced is 1.4 dB (in simulations) and 2 dB (in measurements), indicated its suitability for S‐band application.

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