LAUSR

This letter proposes a structured CANDECOMP/PARAFAC (CP) decomposition-aided (SCPD) pilot decontamination (PDC) scheme for UAV communication in cell-free massive MIMO systems. We design a two-stage pilot transmission scheme and intentionally generate pilot contamination for pilot decontamination. At first, we formulate the received signals as a second-order tensor. Then we turn the PDC problem into a joint channel parameter estimation problem. By exploiting the Vandermonde structure of the factor matrix, we propose a SCPD-aided scheme for channel estimation, which only leverages standard linear algebra and avoids numerous iterations. The simulation results demonstrate the effectiveness of the proposed SCPD scheme in terms of accuracy and complexity.