Abstract
Doppler ambiguity in the range-Doppler domain of linear frequency modulated (LFM) continuous wave radars occurs when a target's Doppler frequency exceeds half of the chirp repetition frequency. Doppler ambiguity is common in a variety of civil and military radar applications, and an extension of the maximal unambiguous Doppler shift is critical for their practical use. This article utilizes previously neglected high-order phase terms in the received LFM radar echo for extension of maximum unambiguous velocity. A computationally feasible velocity estimation algorithm using hypotheses testing with local maximum likelihood is derived. The ability of the proposed low-complexity algorithm to estimate previously ambiguous target velocity is investigated using recorded automotive radar measurements and via simulations. The performance of the proposed algorithm is evaluated using a novel model of the Doppler estimation errors that accounts for Doppler ambiguity. The ability of the derived model to predict the threshold phenomenon is demonstrated via simulations.
Original language | English |
---|---|
Pages (from-to) | 743-751 |
Number of pages | 9 |
Journal | IEEE Transactions on Aerospace and Electronic Systems |
Volume | 58 |
Issue number | 1 |
DOIs | |
State | Published - 1 Feb 2022 |
Keywords
- Ambiguity mitigation
- Automotive radar
- Doppler ambiguity
- Doppler estimation error model
- High-order phase terms
- Linear frequency modulated (LFM) radar ambiguity
ASJC Scopus subject areas
- Aerospace Engineering
- Electrical and Electronic Engineering