title: Radar Principles for the Non-Specialist
author: J.C. Toomay
description: Major General John C. Toomay (ret) is a systems engineering consultant for government and industry. He has more than 25 years experience in research and development and managed major radar programs in the U.S. Air Force and the Defense Advanced Research Projects Agency (DARPA). He has served on the Board of Directors of Texas Instruments and the Air Force Scientific Advisory Board, and has lectured and written frequently on defense technology systems and policy. He currently resides in Carlsbad, CA.
zlib_text: electronics
  Article
  People Walking Classiﬁcation using Automotive
  Radar
  Linda Senigagliesi *
  , Gianluca Ciattaglia, Adelmo De Santis and Ennio Gambi
  Department of Information Engineering, Università Politecnica delle Marche, via Brecce Bianche 12,
  60131 Ancona, Italy; g.ciattaglia@pm.univpm.it (G.C.); adelmo.desantis@univpm.it (A.D.S.);
  e.gambi@univpm.it (E.G.)
  *
  Correspondence: l.senigagliesi@staff.univpm.it (L.S.)
  Received: 24 February 2020; Accepted: 28 March 2020; Published: 30 March 2020
  Abstract: Automotive radars are able to guarantee high performances at the expenses of a relatively
  low cost, and recently their application has been extended to several ﬁelds in addition to the original
  one. In this paper we consider the use of this kind of radars to discriminate different types of
  people’s movements in a real context. To this end, we exploit two different maps obtained from
  radar, that is, a spectrogram and a range-Doppler map. Through the application of dimensionality
  reduction