## 1 Mission Objectives and Constraints
While optimal values for these parameters can be selected and designed accordingly, the purpose here is to illustrate the effect of altitude, assuming that all other parameters remain constant. \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline
**Operating** & **Altitude** & **Incidence** & **Angle** & **System** & **Noise** & **Duty** & **Band** & **Pulse** & **Azimuth-** & **Antenna** & **Peak** & **Swath** & **PRF** \\
**Frequency** & **Atitude** & **Angle** & **Losses** & **Figure** & **Cyde** & **Width** & **Width** & **Range** & **Road** & **Power** & **Swaith** & **Max-Min** \\ \hline
9.65 GHz & 500 km. & 30\({}^{\circ}\) & 5 dB & 3 dB & 0.25 & 150 & 5 \(\mu\)s & 3 m \(\times\) 3 m & 3 m \(\times\) 10 m & 1 kW & 1800 & 2500 2665 \\  & & & & & MHz & & MHz & & & km & & Hz \\ \hline \hline \end{tabular}
\end{table} 
Table 2: System parameters for the desired resolutions. Figure 1: SAR system design flow. To see the system performance, the NESZ effect should be evaluated. If the NESZ decreases, the required transmitting power and antenna area will increase. The results are shown in Figure 5 for NESZ values of +5 dB, \(-\)4 dB, \(-\)10 dB, and \(-\)15 dB by keeping the other parameters and inputs the same as in Table 1. It can clearly be seen that increasing the sensitivity of the system requires too much power and a larger antenna area to reach the desired resolutions. Figure 4: Antenna area–transmitting power for 700 km. Figure 3: Antenna area–transmitting power for 600 km. Figure 2: Antenna area–transmitting power for 500 km. Figure 5. Antenna area-transmitting power for NESZ values (+5 dB, \(-\)5 dB, \(-\)10 dB, \(-\)15 dB). Before evaluating the desired resolution effect on system parameters corresponding to transmitting power and antenna area, other parameters which can be adjusted by technology in hand and engineering capability are presented. That is, the system's loss effect. As mentioned above, it is assumed to vary between 2 dB and 8 dB. Figure 6 shows the required transmitting power and antenna area with the same parameters as in Table 2 but for different system losses of 2 dB, 4 dB, 6 dB, and 8 dB, respectively. Figure 7 shows the effect of bandwidth on the transmitting power and antenna area vs. other parameters used in Table 2.  
Figure 6. Antenna area–transmitting power for system loss values (2 dB, 4 dB, 6 dB, 8 dB). Figure 8 shows the duty cycle on the transmitting power and antenna area vs. other parameters used in Table 2.  
Figure 9 shows the effect of the resolutions on the transmitting power and antenna area. It can be seen that finer resolutions require a greater power and area of the payload. The present work aims to show the effects of various parameters on the antenna area and transmitting power requirements for a SAR system. Decreasing system losses, performance requirements, or choosing coarser resolutions may reduce the antenna area and transmitting power needed. Additionally, increasing the antenna area can lower the power requirements, and vice versa. As mentioned earlier, the final configuration depends on the mission goals and the available technology. Therefore, careful optimization is essential to minimize size and mass. In this paper, although it has been discussed in terms of SNR considerations and their integration with NESZ, the analysis provided can serve as a reference for those aiming to design a smaller SAR system during the early design stages. Figure 1:0 Antenna area–transmitting power for duty cycle values (10%, 20%, 25%, 30%). Figure 1:1 Antenna area–transmitting power for bandwidth values (100 MHz, 150 MHz, 100 MHz, 200 MHz, 250 MHz, 300 MHz).