## 5 Conclusions  
Through simulation analysis, this study attempted to determine the optimal imaging angle and their combinations for the SSR estimation model, whose results will be used to design multi-angle ocean remote-sensing platforms. The simulation results show that an error occurs in the SSR estimation results with exposure to non-ideal conditions, which is closely related to the SVA combination. Optimal SVA combinations can always be selected but change in different environments. Simulations of the pointing angle (\(P\)), sea surface wind speed (\(W\)), and sun zenith angle (\(\theta_{0}\)) showed that, when the pointing angle is directed towards the sun (\(P>0^{\circ}\)), the wind speed is large and the sun zenith angle is small, there is a generation of stronger SG radiance, and there is an improvement in the ratio (\(\rho_{10}\),\(\rho_{20}\)) of the optimal SVA combination. In such cases, the SSR estimation model has a wider application range for the SVA combination. According to the result of the simulation of four key parameters, in the general environment (i.e., the sun is in the east), high accuracy for the SSR estimation results (\(\Delta\sigma_{0}^{2}<20\%\)) is possible with SVA combination (\(\theta_{1}=0^{\circ}\), \(|\theta_{ll}|=20^{\circ}\)) on the ASTER platform. To verify the error transfer simulation model designed in this study, the prediction error output from the model was compared with the actual error. According to Figure 15, although the errors have a large absolute deviation, they have a positive correlation. Therefore, we were able to verify that the simulation model developed in this study has practical usability. Finally, we discussed the relative azimuth combination in multi-angle remote-sensing platforms. The relative azimuth (\(\Delta\phi\)), as part of the imaging angle, can only be optimally adjusted by the sun azimuth (\(\phi_{0}\)) on satellite sensors with fixed flight orbits, such as ASTER. The simulation results show that the relative azimuth is optimal as the sun moves towards the south or north. When the sun azimuth is at 0\({}^{\circ}\)or 180\({}^{\circ}\), the applicable probabilities of the SVA combinations are highest, where \(\rho_{10}\) and \(\rho_{20}\) are approximately 11.0% and 12.4%, respectively. Based on Figure 16, we can use the aviation platform as a multi-angle remote-sensing platform and, thus, the sensor azimuth can also be used to optimally adjust the relative azimuth angle to further improve SSR inversion accuracy. At present, SSR estimation is one of the important applications in multi-angle SG remote sensing, as well as being a topic of current, in-depth research. In ocean dynamics processes, sea surface winds and shallow sea sand wave topography can cause changes in sea surface roughness and, thus, multi-angle SG remote-sensing images can be used to invert the sea surface wind speed [20] and depth of shallow sea sand wave topography [17]. The use of multi-angle SG can also improve our ability to detect sea surface oil spills [13]. By applying an optimal imaging angle to the design of multi-angle ocean sun glitter remote-sensing platforms, we can improve SSR estimation accuracy. This further demonstrates the application potential of multi-angle SG remote sensing in studies on ocean dynamic processes and the detection of phenomena that cause changes in SSR. Methodology, D.W. and H.Z. ; Project administration, L.Z. ; Resources, L.Z. ; Software, D.W.; Validation, J.W., X.L., P.C. and K.F. ; Writing--original draft, D.W. and H.Z. ; Writing--review and editing, A.S. and D.L.