Enhancing the capacity of wireless communications systems is necessary to manage growing networks. Thus, this work presents an analytical model for describing the deterioration in orbital angular momentum (OAM). The proposed model is based on a uniform circular array, which can be applied in OAM generation to obtain the desired beam properties. First, the side-lobe problem in OAM applications is examined and resolved by optimizing the beam synthetization. Then, comparisons between the two window techniques are used to evaluate their impacts. Finally, the effects of selecting the optimal window technique and width on the solutions are investigated. Numerical results and the comparisons between derived formulas and those obtained via full-wave numerical simulations are shown.