A QoS architecture for IDMA-based multi-service wireless networks

The recent investigations on interleave-division multiple-access (IDMA) have demonstrated its advantage in supporting high-data-rate and multi-rate services over wireless fading channels. This paper focuses on quality of service (QoS) guarantee in IDMA-based multi-service wireless networks. We propose a QoS architecture which addresses the key issues of QoS guarantee for multi-service in IDMA, including medium access control (MAC), admission control, power control, and rate allocation. The proposed IDMA QoS architecture avoids complex packet scheduling at the MAC layer which is however required in other existing multiple access systems. Data packets can be transmitted in IDMA without scheduling delay. Additionally, to improve the efficiency of random access, an interleave-division slotted-ALOHA (IDSA) access method is proposed for the IDMA MAC protocol. We derive the relationship between the arrival rate of access requests and the number of access interleavers allocated to an IDMA system for a given access success probability. Based on this relationship, we can adaptively adjust the number of access interleavers according to the traffic load of access requests, so as to ensure a satisfactory probability of successful access as well as low complexity of request detection at the receiver.