This paper describes the design and analysis of a low-power medium access control (MAC) protocol for wireless/mobile ATM networks. The protocol - denoted EC-MAC (energy conserving medium access control) - is designed to support different traffic types with quality-of-service (QoS) provisions. The network is based on the infrastructure model where a base station (BS) serves all the mobiles currently in its cell. A reservation-based approach is proposed, with appropriate scheduling of the requests from the mobiles. This strategy is utilized to accomplish the dual goals of reduced energy consumption and quality of service provision over wireless links. A priority round robin with dynamic reservation update and error compensation scheduling algorithm is used to schedule the transmission requests of the mobiles. Discrete-event simulation has been used to study the performance of the protocol. A comparison of energy consumption of the EC-MAC to a number of other protocols is provided. This comparison indicates the EC-MAC has, in general, better energy consumption characteristics. Performance analysis of the proposed protocol with respect to different quality-of-service parameters using video, audio and data traffic models is provided.