Hsu, K.-C.K.-C.HsuJEAN-FU KIANG2020-06-112020-06-112019https://www.scopus.com/inward/record.uri?eid=2-s2.0-85060131215&doi=10.3390%2fs19020335&partnerID=40&md5=b0f3fca1db86c9c74535e58da98998f6A two-stage method is proposed to jointly estimate the direction-of-arrival (DOA) and carrier frequency (CF) of multiple sources, by using two orthogonal coprime arrays (CPAs). The DOAs of CF-known sources are estimated first by applying a spatial smoothing MUSIC algorithm. The contribution of these source signals is then removed from the originally received signal by applying an orthogonal complement projector. Next, a joint-ESPRIT algorithm is applied to estimate the DOAs and CFs of the remaining CF-unknown sources. With two orthogonal CPA(5, 6), the RMSE of DOA and CF of applying the proposed method to 30 sources, 13 of which have unknown CF, is less than 1% at SNR > 5 dB. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.Array signal processing; Carrier frequency; Coprime array; Direction-of-arrivalArray processing; Frequency estimation; Tunneling (excavation); Array signal processing; Carrier frequency; Coprime; ESPRIT algorithm; MUSIC algorithms; Orthogonal complements; Spatial smoothing; Two-stage methods; Direction of arrivaljournal article10.3390/s190203352-s2.0-85060131215