Algorithm 2: Refined DOA–range estimation by pseudo-noise resampling.

Input: The received data X, initial parameter estimator $({\widehat{\theta }}_k,{\widehat{r}}_k)$.

1. Set the threshold area and apply the threshold detection to these estimators.

2. If it passes the detection, terminate this algorithm and output the estimator of $\widehat{\theta }$ and $\widehat{r}$.

3. If not, W groups of the resampled data are obtained by using the pseudo-noise matrix.

(1) For the updated X, use the algorithms in Section 3.2 and Section 3.3 to estimate the DOA and range.

(2) Perform the threshold detection again for W group estimators and categorize them as (34).

If J > 0, then estimate target parameters via (35).

If J = 0, then select target parameters by (36) and (37).

Output:$\{{\widehat{\theta }}_k,{\widehat{r}}_k\}$