Research on FOA and TOA Estimation Algorithm of Galileo SAR Signal

In order to estimate FOA and TOA accurately in Galileo Search and Rescue system by considering that the message bit width and the phase edge time are unknown, we present a new FOA and TOA estimation algorithm which combines the algorithm based on Multiple dimensions Joint Maximum Likelihood Estimation criterion and Barycenter calculation algorithm. The FOA and TOA estimation errors of this algorithm can be limited within 0.03 Hz and 12 us in the condition that carry-to-noise rate (CNR) equals to CNR treatment threshold which is 34.8 dBHz and phase edge time is 250 us for received signals. Theoretical analysis and measurement results have proved the effectiveness of this algorithm. And the algorithm has been applied to the Galileo MEOLUT station.