## 2 Theoretical Background and Literature Review
### Analytic Hierarchy Process (AHP)  
In our investigation, the Analytic Hierarchy Process (AHP) is employed to dissect and understand the multifaceted decision-making landscape inherent in 5G antenna manufacturing. While the task may appear straightforward, the underlying complexities and interdependencies between factors such as 'Subject', 'Environment', and 'Resources' are substantial. These factors involve layered considerations of technical specifications, environmental conditions, and resource allocation, each with a significant impact and influence on the others. The AHP allows us to deconstruct these complex relationships into a hierarchical framework for systematic evaluation and comparison, providing a quantitative basis for integrating blockchain technology where it can be most effective. Moreover, the subjective judgments inherent in determining priorities among these factors are converted into a quantitative form through the AHP, bringing a level of objectivity to decisions traditionally driven by expert opinion. This quantification is essential in a field where technological advancements rapidly change the parameters of decision-making. Through the AHP, we ensure that our recommendations for blockchain integration are rooted in a comprehensive analysis of all relevant factors, objectively measured and compared. This meticulous approach is vital for substantiating our proposal and reinforcing the integration strategy's alignment with industry-specific challenges and objectives [88,89]. The AHP fundamentally relies on the method of pairwise comparisons. Similar to choosing the best new office location by systematically contrasting pairs of locations against various factors like cost and amenities, AHP evaluates each pair to determine which better fulfills a given criterion. This detailed method allows for a refined analysis, effectively quantifying subjective preferences by measuring the degree of preference for one option over another, a process often complex in nature [90, 91, 92, 93, 94, 95, 96, 97, 98]. Consistency is the linchpin of the AHP method. The process goes beyond making isolated pairwise comparisons; it requires that these comparisons collectively manifest a coherent judgment. To achieve this, the AHP employs a consistency index that scrutinizes the logical coherence of the decisions. This index is crucial; it ensures that the resultant decision is not only reliable but also logically sound, reinforcing the robustness of the decision-making process. The true value of the AHP is most apparent when decision-makers encounter scenarios where standard data analysis falls short. It has the unique capability to distill the insights and intuitive judgments of experienced professionals into tangible data that can guide pivotal decisions. Since its inception in the 1970s, the AHP has become an indispensable tool for navigating complex decision-making landscapes, applicable in a wide array of fields, from shaping public policy to crafting nuanced business strategies [99, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100]. [PERSON] and [PERSON] [110] utilized the SER-M model in conjunction with the AHP to examine the key factors influencing a company's digital transformation strategy. Their study centered on identifying and assessing the essential elements crucial for the successful execution of these strategies, with a particular focus on the dynamic capabilities and resources of an organization. The goal was to establish a comprehensive framework and decision-making model to assist businesses in navigating digital transformation, especially in the context of rapidly changing technology landscapes. [PERSON] et al. [111] employed the AHP alongside blockchain technology to develop an innovative credit rating system. [PERSON] and [PERSON] [112] combined the AHP with blockchain technology to tackle specific challenges in Martian building management. Their research aimed at pinpointing and prioritizing the vital factors for effective building information management under the harsh conditions of Mars.