Expanding the Unambiguous Velocity Limitation of the Stepped-Carrier OFDM Radar Scheme

Abstract

The main limitation for the practical implementation of OFDM radars is the required high sampling rate of AD/DA converters. It can be solved by using a stepped-carrier OFDM scheme. Thereby, the same range and Doppler resolution is obtained as for a standard OFDM scheme at the cost of a reduced unambiguously measurable velocity. This paper presents a method to determine the actual velocity even for targets that violate the unambiguous velocity limitation. It is based on characteristics of the DFT and it is suitable for scenes with few targets or if all targets have a similar velocity.