Phunchongharn Phond, Hossain Ekram, Camorlinga Sergio
Department of Electrical and Computer Engineering, University of Manitoba, Winnipeg, Manitoba, Canada.
IEEE Trans Inf Technol Biomed. 2011 Nov;15(6):890-9. doi: 10.1109/TITB.2011.2164258. Epub 2011 Aug 12.
We study the multiple access problem for e-Health applications (referred to as secondary users) coexisting with medical devices (referred to as primary or protected users) in a hospital environment. In particular, we focus on transmission scheduling and power control of secondary users in multiple spatial reuse time-division multiple access (STDMA) networks. The objective is to maximize the spectrum utilization of secondary users and minimize their power consumption subject to the electromagnetic interference (EMI) constraints for active and passive medical devices and minimum throughput guarantee for secondary users. The multiple access problem is formulated as a dual objective optimization problem which is shown to be NP-complete. We propose a joint scheduling and power control algorithm based on a greedy approach to solve the problem with much lower computational complexity. To this end, an enhanced greedy algorithm is proposed to improve the performance of the greedy algorithm by finding the optimal sequence of secondary users for scheduling. Using extensive simulations, the tradeoff in performance in terms of spectrum utilization, energy consumption, and computational complexity is evaluated for both the algorithms.
我们研究了在医院环境中，电子健康应用程序（称为次要用户）与医疗设备（称为主要或受保护用户）共存时的多址接入问题。具体而言，我们专注于多空间复用时分多址（STDMA）网络中次要用户的传输调度和功率控制。目标是在满足有源和无源医疗设备的电磁干扰（EMI）约束以及次要用户的最小吞吐量保证的前提下，最大化次要用户的频谱利用率并最小化其功耗。多址接入问题被表述为一个双目标优化问题，结果证明它是NP完全问题。我们提出了一种基于贪心方法的联合调度和功率控制算法，以更低的计算复杂度解决该问题。为此，提出了一种增强贪心算法，通过找到用于调度的次要用户的最优序列来提高贪心算法的性能。通过广泛的仿真，对这两种算法在频谱利用率、能耗和计算复杂度方面的性能权衡进行了评估。
