Achievable performance of dynamic channel assignment schemes under varying reuse constraints

Abstract

We introduce a reward paradigm to derive novel bounds for the performance of dynamic channel assignment (DCA) schemes. In the case of uniform reuse, our bounds closely approach the performance of maximum packing (MP), which is an idealized DCA scheme. This suggests not only that the bounds are extremely tight, but also that no DCA scheme, however sophisticated, will be able to achieve significant capacity gains beyond those obtained from MP. Our bounds extend to varying reuse scenarios which may arise in the case of reuse partitioning techniques, measurement-based DCA schemes, or micro-cellular environments. In these cases, the bounds slightly diverge from the performance of MP, which inflicts higher blocking on outer calls than inner calls, but not to the extent required to maximize carried traffic. This reflects the inherent tradeoff that arises in the case of varying reuse between efficiency and fairness. Asymptotic analysis confirms that schemes which minimize blocking intrinsically favor inner calls over outer calls, whereas schemes which do not discriminate among calls inevitably produce higher network-average blocking. Comparisons also indicate that DCA schemes are crucial in fully extracting the potential capacity gains from tighter reuse.