which was further extended to the Licensed Shared Access (LSA) frame- work by several European institutions, including the European Conference of Postal and Telecommunications Administrations (CEPT), the European Commission (EC), and the Radio Spectrum Policy Group (RSPG) of the European Union (EU). The main objective of LSA is to allow new users to work in already-occupied frequency bands while maintaining existing incumbent services on a long-term basis. The LSA framework is currently switched to explore the 3.4-3.8 GHz band from the 2.3-2.4 GHz band, enabling coexistence between incumbents and 5G applications [127, 144]. Similar to the LSA framework, the US Federal Communications Commission (FCC) proposed the Citizens Broadband Radio Service (CBRS) in order to open and share the fre- quency band 3.55-3.7 GHz. It sought to improve spectrum usage by allowing commercial users to share the band with incumbent military radars and satellite earth stations. In this approach, the access and user coordination are controlled by the corresponding Spectrum Access System (SAS). SAS comprises three types of users with different levels of priority. The first type is Incumbent Users (IUs), which have the highest spectrum access priority. The second is the Priority Access License (PAL) users, which can exclusively access the spectrum without the existence of IUs. The third is General Authorized Access (GAA) users, who have sensing-assisted unlicensed access in the absence of the incumbent and PAL users. SAS determines the maximum allowable transmission power level and the available frequencies at a given location to be assigned to PAL and GAA users [127, 144]. It should be noted that both LSA and SAS systems are defined for usage in a specific fre- quency band. LSA is mainly based on database-assisted SS, while SAS combines a database with Environmental Sensing Capability (ESC) protections. Thus in SAS, the radio resources allocation decision is obtained with assistance from the spectrum database and sensing results. The ESC c