Two-best user scheduling for high-speed downlink multicode CDMA with code constraint

This paper addresses the issue on how the code constraint affects the design of scheduling when multicode CDMA with high-order modulation is adopted for downlink best-effort packet data. For this, two-best user scheduling is proposed for proper trade-off between sum-rate throughput and short-term fairness, while the code and power constraints are effective along with high-order modulation over multicode. To clearly show the trade-off, conventional pure opportunistic, proportional fair, and round robin schedulings are compared with the proposed one, for which a theoretical framework for evaluation of the sum-rate throughput is developed to derive a closed-form formula, taking into account both short-term and long-term fadings.