Department of Electrical Engineering, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul, 136-713, Korea.
Sensors (Basel). 2011;11(7):6629-44. doi: 10.3390/s110706629. Epub 2011 Jun 27.
Nowadays, with wireless sensor networks (WSNs) being widely applied to diverse applications, heterogeneous sensor networks (HSNs), which can simultaneously support multiple sensing tasks in a common sensor field, are being considered as the general form of WSN system deployment. In HSNs, each application generates data packets with a different size, thereby resulting in fairness issues in terms of the network performance. In this paper, we present the design and performance evaluation of a differentiated channel access scheme (abbreviated to DiffCA) to resolve the fairness problem in HSNs. DiffCA achieves fair performance among the application groups by providing each node with an additional backoff counter, whose value varies according to the size of the packets. A mathematical model based on the discrete time Markov chain is presented and is analyzed to measure the performance of DiffCA. The numerical results show that the performance degradation of disadvantaged application groups can be effectively compensated for by DiffCA. Simulation results are given to verify the accuracy of the numerical model.
如今，随着无线传感器网络（WSN）广泛应用于各种应用，异构传感器网络（HSN），它可以同时支持在一个共同的传感器领域的多个传感任务，被认为是 WSN 系统部署的一般形式。在 HSN 中，每个应用程序生成具有不同大小的数据分组，从而导致网络性能方面的公平性问题。在本文中，我们提出了一种区分信道接入方案（简称 DiffCA）的设计和性能评估，以解决 HSN 中的公平性问题。DiffCA 通过为每个节点提供一个附加的回退计数器来实现应用程序组之间的公平性能，该计数器的值根据数据包的大小而变化。提出了一种基于离散时间马尔可夫链的数学模型，并对其进行了分析，以衡量 DiffCA 的性能。数值结果表明，DiffCA 可以有效地补偿不利应用程序组的性能下降。给出了仿真结果以验证数值模型的准确性。
