{"abstract":"In this document, the Commission seeks comment on the use of a terrain-based propagation model such as Longley-Rice for determining white space channel availability and seeks to develop a record on whether or not to implement such a model. In particular, the Commission seeks comment on the effect use of such a model would have on availability of channels for white space devices, how a terrain-based model such as Longley-Rice could be implemented within the current white space device framework, the technical parameters necessary to use such a model for identifying available spectrum while protecting incumbents from harmful interference, and various database and device implementation issues.","action":"Proposed rule.","agencies":[{"raw_name":"FEDERAL COMMUNICATIONS COMMISSION","name":"Federal Communications Commission","id":161,"url":"https://www.federalregister.gov/agencies/federal-communications-commission","json_url":"https://www.federalregister.gov/api/v1/agencies/161","parent_id":null,"slug":"federal-communications-commission"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2021/02/25/2021-03437.html","cfr_references":[{"chapter":null,"citation_url":null,"part":15,"title":47}],"citation":"86 FR 11490","comment_url":null,"comments_close_on":"2021-03-29","correction_of":null,"corrections":[],"dates":"Comments are due on or before March 29, 2021; reply comments are due on or before April 26, 2021.","disposition_notes":null,"docket_ids":["ET Docket No. 20-36","FCC 20-156","FRS 17403"],"dockets":[],"document_number":"2021-03437","effective_on":null,"end_page":11494,"executive_order_notes":null,"executive_order_number":null,"explanation":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2021/02/25/2021-03437.xml","html_url":"https://www.federalregister.gov/documents/2021/02/25/2021-03437/unlicensed-white-space-device-operations-in-the-television-bands","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/2021-03437?publication_date=2021-02-25","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2021-02-25/2021-03437/mods.xml","not_received_for_publication":null,"page_length":5,"page_views":{"count":315,"last_updated":"2026-04-24 16:15:04 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2021-02-25/pdf/2021-03437.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":"https://public-inspection.federalregister.gov/2021-03437.pdf?1614174316","publication_date":"2021-02-25","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2021/02/25/2021-03437.txt","regulation_id_number_info":{},"regulation_id_numbers":[],"regulations_dot_gov_info":{"comments_count":0,"agency_id":"FCC","document_id":"FCC-2021-0011-0003","checked_regulationsdotgov_at":"2023-02-28T18:06:48Z"},"regulations_dot_gov_url":null,"significant":null,"signing_date":null,"start_page":11490,"subtype":null,"title":"Unlicensed White Space Device Operations in the Television Bands","toc_doc":"Unlicensed White Space Device Operations in the Television Bands","toc_subject":null,"topics":[],"type":"Proposed Rule","volume":86}