eprintid: 10189915 rev_number: 6 eprint_status: archive userid: 699 dir: disk0/10/18/99/15 datestamp: 2024-04-04 14:51:21 lastmod: 2024-04-04 14:51:21 status_changed: 2024-04-04 14:51:21 type: article metadata_visibility: show sword_depositor: 699 creators_name: Chian, DM creators_name: Wen, CK creators_name: Wu, CH creators_name: Wang, FK creators_name: Wong, KK title: A Novel Channel Model for Reconfigurable Intelligent Surfaces with Consideration of Polarization and Switch Impairments ispublished: inpress divisions: UCL divisions: B04 divisions: C05 divisions: F46 keywords: Channel models , Reconfigurable intelligent surfaces , Antennas , Switches , Wireless communication , Phase shifters , Metals note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. abstract: Future wireless networks require the ability to actively adjust the wireless environment to meet strict performance indicators. Reconfigurable Intelligent Surface (RIS) technology is gaining attention for its advantages of low power consumption, cost-effectiveness, and ease of deployment. However, existing channel models for RIS often ignore important properties, such as the impairment in the RIS’s switch component and the polarization efficiency among antennas, limiting their practical use. In this paper, we propose a new channel model for RIS that considers these ignored properties, including the reflected field, scattered field, and antenna resonant mode. We verify the proposed model through practical implementation of a 4 × 4 RIS array with patch antennas in the 3.5 GHz band, using a phase shifter as the switch component of a RIS element. The equivalent model of the phase shifter is also formulated and incorporated into the channel model. We propose a blind controlling algorithm to discuss the properties of our channel model and emphasize the importance of considering polarization and tracking mechanisms for the controlling algorithm. Our channel model is an improvement over existing models and can be used in the practical design of RIS technology. The proposed algorithm provides a practical approach to controlling the wireless environment, suitable for various wireless applications. date: 2024-03-07 date_type: published publisher: Institute of Electrical and Electronics Engineers (IEEE) official_url: http://dx.doi.org/10.1109/tap.2024.3372131 oa_status: green full_text_type: other language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2262451 doi: 10.1109/TAP.2024.3372131 lyricists_name: Wong, Kai-Kit lyricists_id: KWONG98 actors_name: Wong, Kai-Kit actors_id: KWONG98 actors_role: owner full_text_status: public publication: IEEE Transactions on Antennas and Propagation citation: Chian, DM; Wen, CK; Wu, CH; Wang, FK; Wong, KK; (2024) A Novel Channel Model for Reconfigurable Intelligent Surfaces with Consideration of Polarization and Switch Impairments. IEEE Transactions on Antennas and Propagation 10.1109/TAP.2024.3372131 <https://doi.org/10.1109/TAP.2024.3372131>. (In press). Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10189915/1/RISmodel-2022-xxx-R1.pdf