DCAM/LP (dynamic channel adaptive MAC with frame length prediction): A new MAC protocol for wireless networks.

摘要

Wireless Communication, either in the form of wireless local area networks or wireless hand held devices, is gaining popularity with the number of users and devices increasing at a very rapid pace. Modern wireless devices are capable of transmitting voice and video as well as text. In such a multi-service wireless environment, the Quality-of-Service (QoS) guarantees are critical for real-time voice and video as well as for data transmission.; Networks with small fixed size packets as in the Asynchronous Transfer Mode (ATM) are expected to be used in the next generation wireless communications. Although the ATM networks did not reach their potential, the idea of using fixed and small size packets (cells) is gaining wide acceptance in the wireless networks. Small fixed size packets result in fast switching. Also, resource reservation is easier for small fixed size packets as compared with variable size packets such as IP packets. Among the layers of the wireless protocol stack, the Medium Access Control (MAC) layer is crucial for the system performance since MAC layer schedules the transmission of each cell, thus affecting the overall performance and QoS.; Our research aims at designing a wireless MAC protocol that guarantees QoS in a multi-service cellular environment under noisy channel conditions. We concentrate on two aspects of MAC: slot assignment and error handling. For slot assignment, we introduce a new scheduling algorithm that uses a new "frame length prediction" technique. For error handling, we investigate an adaptive Forward Error Correction (FEC)/Automatic Repeat Request (ARQ) hybrid scheme to guarantee the transmission quality under noisy channel conditions. Our experimental results illustrate that the performance of our protocol is superior to the previously known protocols.