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


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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    ABSTRACT: In the design of wireless scheduling policies, the fairness criterion plays an important role in upgrading the performance of network. This paper concentrates on how the channel-aware opportunistic scheduler can improve both throughput and fairness in cellular wireless networks. In order to improve the fairness, we propose an adaptive fair scheduling algorithm by using fuzzy logic model. Proposed scheduler operates on Time Division Multiple Access (TDMA) fashion and calculates the priority index of each user according to channel quality fed back and fairness of channel assignment. We evaluate its performance via statistical simulations. The obtained results show that our strategy can improve the fairness but at the expense of slight throughput loss compared to well-known opportunistic scheduling methods.
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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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