Ultrawideband Radar Using Communications ActivityBryan WestcottIntroduction• Ultrawideband radar and communications use the same baseband processing and similar receiver design• Reuse hardware and network activity• Applications include: location-based services, indoor GPS, location-based security, augmented realityBackground• Existing RF triangulation based on received power• IEEE 802.15 TG4a WPAN Task Group working on implementation• Multi-user detection an optimal solution• Successive interference cancellation one of few practical implementations• Essentially distributed radarMethod 1: Signature-Based• Implements echolocation with ultrasound [Kazys, 2000]• Based on early echolocation in bats and optimum correlation techniques [Altes, 1978]• Once LOS distance is known, fit to best signature• Suggests use of cyclic deconvolution with CDMA• Extends perfectly to distributed radarMethod 2: Range-based• Range data relocation [Jong & Leonard, 2000]• Specular propagation• Pair-wise interpretation-tree algorithm • MMSE all possible positions • occlusion test• Feature map localization [Kuc & Seigel, 1987] • using regions of constant depth • multiple measurement• fit walls between corners • known shadow regions• Translation and rotation [Santamaria, 1994] • Extends to distributed environment using ellipses with time-of-flight infoMethod 3: Source Localization• Localization using vector sensor array in multipath environment [Rahamin, et al, 2004]• Uses MUSIC, ESPRIT eigenstructure algorithms• Polarization smoothing for correlated signals• Extensions to wideband channel [Goncalves & Gounon, 1998]• DOA information reduces complexity, good for multi-antenna
View Full Document
Unlocking...