Study of advanced-opportunistic proportionate fairness scheduler for LTE medium access control

摘要

Medium Access Control (MAC) scheduler entity forms one of the most important parts of any high speed packet access system like HSDPA or LTE. To the best of our knowledge the LTE MAC schedulers that had been proposed so far constitute of sub-carrier resource scheduling mostly based on single criteria like user throughput, link conditions, buffer constraints or power requirement. The above LTE MAC scheduler algorithms do not take care of user's queue weight calculation taking all the above mentioned parameters into consideration. In this paper, we proposed a novel algorithm to support dynamic queue weight calculation and referred it as Advanced-Opportunistic Proportionate Fairness Scheduler for LTE (A-OPFS-LTE). The A-OPFS-LTE, calculates the queue weight based on multiple parameters like flow control feedback, hybrid automatic repeat request (HARQ) retransmission status, service class type, guaranteed bit rate, access terminal (AT's) channel condition, queue's buffer utilization and later assigns the physical resource block. A-OPFS-LTE was able to schedule 14 uncompressed VoIP calls or 5 streaming type video calls every 1 milli-second scheduling cycle with packet loss less than 2%. Compared with MAC scheduler [10, 11], A-OPFS-LTE scheduler supports 10% cell throughput improvement and 30% more users