Frequency diverse array with random logarithmically increasing frequency offset

The frequency diverse arrays (FDAs) have been extensively investigated since it can provide a unique angle-range-dependent beampattern. This range-dependent characteristic can suppress the range ambiguous clutters, leading to many novel potential Radar applications. Two issues, however, exist in conventional FDA (CFDA) beampatterns, that is, range-angle coupling and range periodicity. Therefore, for a CFDA Radar, target range information cannot be obtained directly from the beampattern peaks and target ambiguity occurs in the range domain. In this work, a new frequency diverse array (FDA) transmitter architecture with random logarithmically increasing frequency offset (log-RFDA) is presented. It is shown that the proposed strategy provides a nonperiodic thumbtack-like beampattern, eliminating the ambiguity in range domain, suffered in the CFDA Radar. Furthermore, reduced side lobe and higher detection resolution can be achieved, compared with the previously reported log-FDA.