Publication: IEICE TRANSACTIONS on Communications Publication Date: 2011/11/01 Vol. E94-BNo. 11pp. 2987-2990 Type of Manuscript: Special Section LETTER (Special Section on Space, Aeronautical and Navigational Technologies in Conjunction with Main Topics of WSANE and ICSANE) Category: Keyword: microwave measurement, free space method, snow, ice, winter road maintenance,