This paper deals with the performance evaluation of different channel resource management techniques in LEO satellite systems based on an earth-fixed cell concept. Furthermore, in order to reduce the handover failure probability, we assumed that handover attempts can be queued. Both fixed and mobile users have been considered resulting in several classes of users. Each class requires a given Quality of Service (QoS) and thus a fixed part of the shared resource. Two channel allocation techniques are investigated: fixed channel allocation (FCA) and dynamic channel allocation (DCA). An analytical model is derived to analyze the performance of the FCA scheme supporting different kinds of users. A second analytical approch is proposed, in the FCA case, where a handover queuing strategy is taken into account. Implementation aspects for FCA and DCA strategies are discussed and compared in terms of blocking probabilities relative to each type of users.