In this paper we study the performance of packet reservation frame-based MAC protocols for wireless ATM networks. We evaluate the impact on the protocol performance of the frame size, the ratio between the request and data periods, the buffering capacity of the mobiles and the transmission errors due to a non-ideal channel. We consider a two-state Markov model for the non-ideal channel. Results suggest that performance optimization requires dynamic adaptation of the protocol parameters to the QoS requirements, and the traffic load and wireless channel conditions.