The continued growth of customer demand in Ethiopia, having more than 65 million subscribers with a 95% population and 85.4% geographic coverage. The ever-increasing customer rise in data traffic and mobile services. The telecom and radio-frequency regulatory body, which is Ethiopian Communication Authority (ECA), has drafted a directive that compels Ethio-telecom to add two additional competitive operators which demand spectrum. With the development of wireless communication technology, the need for bandwidth is increasing continuously, and the growing need makes wireless spectrum resources scarce. One of the most important issues in spectrum sharing is to determine the potential benefit when multi-operators share resources under certain mutual agreements. However, the main problem with sharing nearly the same frequency bands without coordination may cause interference and call congestion which can affect the quality of services and system capacities. To overcome this problem, the operators need careful planning to mitigate the problem. This study has modeled and analyzed interactions between these upcoming competitive operators that coexist in the same frequency band as a strategy. The study proposes efficient dynamic solutions to provide secondary access to under-utilized spectrum to address optimization problems and network models by deriving expressions of blocking probability. Also, analyzing the overall network performance in terms of spectrum utilization and of the analytical frameworks are presented to analyze the benefits of multi-operator cooperation for spectrum sharing. Results mainly focused on comparison of sharing models' performance to show the impact of blocking probability(Pb); probability of detection(Pd) and signal to noise ratio(SNR) of the system at different parameters like number of servers, service rate, offered load, arrival rate and channel capacity of network operators to ensure efficient spectrum sharing. In addition to spectrum sharing, spectrum sensing is also the major challenge in dynamic spectrum sharing (DSS). The performance of the energy detection algorithm is analyzed and simulated. Results show that the blocking probability is reduced by using unidirectional, bi-directional and bidirectional with reserved capacity models compared with the nonsharing model. Keywords: Blocking Probability, Cognitive Radio, Dynamic Spectrum Sharing, Multi operator