# A Model-Based Engineering Approach for Evaluating Software-Defined Radio Architecture
## 5 Multi-Criteria Decision-Making Analysis
Each matrix was initially normalized, and then the ARS were calculated using equations 10 and 11, respectively. This process was repeated for each SME, and the resulting scores are displayed in Table 4 and Figure 17. Throughout the process, the CR was calculated using the method from Reference [33] and monitored. If any inconsistency was identified (CR > 0.1), a request was made to the SMEs to adjust their pairwise comparisons. Only the final and consistent results (CR < 0.1) are presented in this paper. The scores are given as values between 0 and 1. The score assigned to each alternative is weighted across criteria based on the importance of the criteria using Equation (12), and the overall score for each alternative is calculated by summing up the scores from the three SMEs, as illustrated in Table 5.  
\[b_{ij}=\frac{a_{ij}}{\sum_{i=1}^{n}a_{ij}} \tag{10}\]  
\[ARS=\frac{\sum_{i=1}^{n}b_{ij}}{n} \tag{11}\]  
\[WCS=W.Cr_{i}*S.Cr_{i} \tag{12}\]  
where \(n\), \(ARS\), \(WCS\), \(W.Cr\), and \(S.Cr\) represent the number of assessment criteria, the average row score, weighted criterion score, criterion weight, and criterion score, respectively. The CONOP was designed to enhance the single-channel NB receive capability to complement other system capabilities. The primary objective was to demonstrate robustness in the system's performance in defense-related applications. The assumption was that the customer preferred robustness in the system's performance over other factors, such as cost and weight. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Cr.** & **SME1** & **SME2** & **SME3** \\ \hline Cr.1 & 0.09 & 0.06 & 0.07 \\ Cr.2 & 0.18 & 0.15 & 0.19 \\ Cr.3 & 0.55 & 0.52 & 0.43 \\ Cr.4 & 0.18 & 0.28 & 0.31 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Normalized Criteria weights based on SME inputs. Three architectures were considered to achieve the CONOP, each with its unique design and components. Each architecture was evaluated based on four criteria, with the most essential being performance related, followed by reliability. The data showed that all three alternatives met the CONOP and stakeholder needs, but architectures 2 and 3 have higher scores for criteria 3 and 4, which are related to robustness and reliability, as illustrated in Figure 17. This is because these architectures have an additional channel, which provides better performance and reduces the risk of system failure. The cost and weight of the alternatives were also considered in the evaluation. It was found that there was no significant increase in cost from Architecture 1 to 2, but Architecture 3 had a significant increase in cost and weight due to the use of an active thermal solution, a second FPGA, and a larger enclosure. Based on the data, Architecture 2 was found to be the most favorable among the three alternatives, with an overall score of 1.20. This suggests that it offers the best balance of performance, robustness, reliability, and cost. Architecture 1 had the lowest overall score of 0.70, which can be attributed to its lack of robustness, as it only has a single channel. A limited sensitivity study was conducted on our methodology/AHP approach. This was performed by assessing the average weights over a \(\pm\)10% and 20% range for each \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Arch.** & **SME** & **Cr.1 Score** & **Cr.2 Score** & **Cr.3 Score** & **Cr.4 Score** \\ \hline \multirow{3}{*}{Arch.1} & SME1 & 0.57 & 0.47 & 0.20 & 0.17 \\  & SME2 & 0.43 & 0.45 & 0.10 & 0.13 \\  & SME3 & 0.54 & 0.56 & 0.11 & 0.14 \\ \hline \multirow{3}{*}{Arch.2} & SME1 & 0.29 & 0.38 & 0.40 & 0.33 \\  & SME2 & 0.43 & 0.45 & 0.33 & 0.51 \\  & SME3 & 0.30 & 0.32 & 0.44 & 0.43 \\ \hline \multirow{3}{*}{Arch.3} & SME1 & 0.14 & 0.15 & 0.40 & 0.50 \\  & SME2 & 0.14 & 0.09 & 0.57 & 0.36 \\ \cline{1-1}  & SME3 & 0.16 & 0.12 & 0.44 & 0.43 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Criteria scores for each alternative.