Numerous types of research have been done in recent years on Multi-Input, Multi-Output, and Massive Multi Input Multi Output. In all of these researches, intercell interface, delay, and Spectral Efficiency have been evaluated. Although Massive MIMO standards in 5G spectral efficiency, Energy efficiency, delay, etc., have been improved significantly, intercell interference issues and handover impact the performance and users' services at the edge of the cell intensely. Cell-Free Massive Multi Input Multi Output as an emerging technology to prepare the users increasing demands and expected increased data rate beyond 5G networks has attracted considerable attention. The main idea of this project is that several distributed Access Points on a limited number of users in one time-frequency block are responsible for the service. In this case, each user receives the services from APs that have the minimum power to delete the intercell interface. Considering the high signaling volume to estimate the channel, signal processing, cooperation, and contribution of APs, it originates essentially to evaluate different levels of signal processing implementation. In this thesis, accomplishments have been made to evaluate four different levels of signal processing or user-centric processing, which are in the best performance. In addition, drone UAVs have been reviewed, which has better performance than user-centric scenarios.
