Matched-field estimation of aircraft altitude from multiple over-the-horizon radar revisits


Journal Article

Over-the-horizon (OTH) radar uses the refractive properties of the ionosphere for wide-area surveillance of targets at long ranges. Currently, OTH radars can localize targets in latitude and longitude but have difficulty estimating target altitude, which is important for classification purposes. Methods that have been proposed for aircraft altitude estimation using OTH radar take advantage of micro-multipath returns due to ground reflections local to the aircraft and are typically limited in performance by radar bandwidth and observation time. In previous work, electromagnetic matched-field processing was proposed for estimating aircraft altitude using a single dwell by exploiting the altitude dependence of unresolved multipath returns in complex range-Doppler space. However, the performance of the single-dwell method suffers in situations where the coherent integration time (CIT) of the radar is short. To overcome this limitation, this paper presents a matched-field estimation approach that exploits the altitude dependence of dwell-to-dwell shape changes of the complex range-Doppler multipath return as the basis for multi-dwell maximum likelihood (ML) altitude estimation. Monte Carlo simulation results indicate that using a short CIT, moderate signal bandwidth, and 30-s revisit rate, multi-dwell matched-field altitude estimation can achieve better than ±2500 ft accuracy after as few as four radar dwells. The results of processing actual radar data for both high-flying commercial aircraft and a low-flying twin engine aircraft are also presented and validated against aircraft altitude ground truth.

Full Text

Duke Authors

Cited Authors

  • Papazoglou, M; Krolik, JL

Published Date

  • April 1, 1999

Published In

Volume / Issue

  • 47 / 4

Start / End Page

  • 966 - 976

International Standard Serial Number (ISSN)

  • 1053-587X

Digital Object Identifier (DOI)

  • 10.1109/78.752595

Citation Source

  • Scopus