Conference Paper

Spectral Efficiency and Fairness for Opportunistic Round Robin Scheduling

Norwegian University of Science and Technology, Dept. of Electronics and Telecommunications, 7491 Trondheim, Norway, email:
DOI: 10.1109/ICC.2006.254803 Conference: Communications, 2006. ICC '06. IEEE International Conference on, Volume: 2
Source: IEEE Xplore

ABSTRACT In this paper we analyze the Opportunistic Round Robin (ORR) scheduling algorithm [1], [2]. This algorithm is able to exploit multiuser diversity (MUD) and at the same time provide short-term fairness between the users in a wireless cellular network. We analyze the spectral efficiency and the fairness for two scenarios. In the first scenario all the users have the same average carrier-to-noise ratios (CNR) and for the second scenario the users have different average CNRs. For the first scenario the absolute MUD is exploited while we exploit the so-called relative MUD between the users for the second scenario. The advantages and disadvantages of the different ORR implementations are highlighted by analyzing plots of our closed-form expressions.

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Available from: Geir E. Øien, Nov 24, 2014
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    • "The ORR scheduling algorithm can be combined with maximum NSNR scheduling to achieve higher throughput than ORR, by scheduling the user with highest NSNR. This algorithm is denoted as the normalized ORR (N-ORR) [11] "
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    • "On the other hand, the well-known round-robin scheduling [9] maximizes the system fairness by selecting a user arbitrarily regardless of its channel conditions. Proportional fair [19] and opportunistic round-robin [22] are two other popular scheduling schemes that lie in between the two extremes in terms of throughput and fairness trade-off. "
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    • "The simple TDMA scheme which uses round-robin scheduling, which we call round-robin (RR) scheme, provides the highest short-term fairness when the time slots are allocated in rounds of K time slots, where K is the number of SNs [13]. Then, the scheduled SNs do not have to contend for the shared medium nor worry about packet collisions since only the owner of the time slot is allowed to transmit a packet. "
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