Nonuniform Stepped Frequency Radar Scheme Reducing Spectrum Occupancy and Data Acquisition Time

Radar systems using stepped frequency signals that are uniformly shifted through a certain band require a high amount of spectrum and also suffer from long data acquisition times needed to provide high resolution and a huge unambiguity range at the same time. In order to break up the limitations in the performance of such a radar system, a nonuniform spacing of frequency steps is described, that allows increasing the update rate as well as reducing the amount of spectrum while retaining multipath resolution and the area that can be unambiguously covered. Similarly, the proposed signal design can also be used to provide an enhanced resolution capability without increasing measurement time and bandwidth utilization. Both can be achieved by the use of certain step patterns including several gaps but allowing for full augmentation of the missing data. In addition to the signal design scheme, a method for the signal processing of the data is described that can be used to achieve a sidelobe level similar to the one obtained when using a conventional uniform pattern utilizing the full amount of bandwidth. In addition to Monte Carlo simulations, the effectiveness of the scheme is proven by laboratory measurements.