## 4 Results, Discussions and Achievements
### Estimation Accuracy  
Results for estimation accuracy of CS and PSO are obtained by setting different parameters as a signal-to-noise ratio, number of sources and their locations. The analysis is performed based on both algorithms' best, mean and worst estimations. In case of six sources, results for estimation accuracy of CS and PSO are quite well at 0 dB, \(-5\) dB and \(-10\) dB as shown in Tables 1-3. Figure 3: The explanation of particle swarm optimization in terms of a flow chart. In the case of the nine sources estimation, the performance of CS is much better than PSO at 0 dB and \(-5\) dB. At \(-10\) dB performance of CS is slightly degraded but even then results are much better as compared to PSO as mentioned in Tables 4-6. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Actual Angles (Degrees)** & & \(\mathbf{\Phi_{1}}\)= 20 & \(\mathbf{\Phi_{2}}\)= 40 & \(\mathbf{\Phi_{3}}\)= 60 & \(\mathbf{\Phi_{4}}\)= 80 & \(\mathbf{\Phi_{5}}\)= 100 & \(\mathbf{\Phi_{6}}\)= 120 \\ \hline \multirow{4}{*}{**CS**} & Best & 19.957 & 40.002 & 59.826 & 79.889 & 99.897 & 120.003 \\  & Mean & 18.563 & 38.750 & 59.726 & 79.373 & 101.009 & 119.917 \\  & Worst & 8.322 & 35.5332 & 58.7853 & 79.738 & 99.970 & 120.058 \\ \hline \multirow{4}{*}{**PSO**} & Best & 20.090 & 39.932 & 59.714 & 79.996 & 100.287 & 120.000 \\  & Mean & 16.361 & 37.489 & 59.579 & 79.983 & 100.113 & 119.697 \\  & Worst & 0.145 & 30.027 & 39.150 & 59.312 & 79.567 & 99.001 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Calculation of accuracy for six targets at 0 dB SNR. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Actual Angles (Degrees)** & & \(\mathbf{\Phi_{1}}\)= 20 & \(\mathbf{\Phi_{2}}\)= 40 & \(\mathbf{\Phi_{3}}\)= 60 & \(\mathbf{\Phi_{4}}\)= 80 & \(\mathbf{\Phi_{5}}\)= 100 & \(\mathbf{\Phi_{6}}\)= 120 \\ \hline \multirow{4}{*}{**CS**} & Best & 19.784 & 39.820 & 59.855 & 79.886 & 100.259 & 119.980 \\  & Mean & 21.610 & 40.151 & 59.092 & 79.256 & 101.344 & 120.111 \\  & Worst & 09.287 & 36.093 & 59.598 & 78.986 & 100.932 & 119.839 \\ \hline \multirow{4}{*}{**PSO**} & Best & 19.961 & 40.075 & 59.884 & 79.839 & 99.788 & 120.000 \\  & Mean & 18.405 & 38.837 & 59.709 & 79.202 & 100.519 & 119.931 \\  & Worst & 0.000 & 32.679 & 39.566 & 58.822 & 79.662 & 98.929 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Calculation of accuracy for six targets at \(-5\) dB SNR. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Actual Angles (Degrees)** & & \(\mathbf{\Phi_{1}}\)= 20 & \(\mathbf{\Phi_{2}}\)= 40 & \(\mathbf{\Phi_{3}}\)= 60 & \(\mathbf{\Phi_{4}}\)= 80 & \(\mathbf{\Phi_{5}}\)= 100 & \(\mathbf{\Phi_{6}}\)= 120 \\ \hline \multirow{4}{*}{**CS**} & Best & 20.470 & 40.140 & 59.923 & 79.942 & 100.017 & 120.297 \\  & Mean & 15.794 & 37.302 & 61.420 & 80.681 & 99.006 & 118.444 \\  & Worst & 33.509 & 58.204 & 77.819 & 101.635 & 121.967 & 180.000 \\ \hline \multirow{4}{*}{**PSO**} & Best & 20.630 & 39.500 & 59.908 & 79.860 & 99.936 & 120.000 \\  & Mean & 16.630 & 36.413 & 59.679 & 78.153 & 101.692 & 120.000 \\ \cline{1-1}  & Worst & 16.630 & 36.413 & 59.679 & 78.153 & 101.692 & 120.000 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Calculation of accuracy for six targets at \(-10\) dB SNR.