Distributed cognitive coexistence of 802.15.4 with 802.11

Abstract

Thanks to recent advances in wireless technology, a broad range of standards are currently emerging. Interoperability and coexistence between these heterogeneous networks are becoming key issues, which require new adaptation strategies to avoid harmful interference. In this paper, we focus on the coexistence of 802.11 Wireless LAN and 802.15.4 sensor networks in the ISM band. Those networks have very different transmission characteristics that result in asymmetric interference patterns. We propose distributed adaptation strategies for 802.15.4 nodes, to minimize the impact of the 802.11 interference. This interference varies in time, frequency and space and the sensor nodes adapt by changing their frequency channel selection over time. Different distributed techniques are proposed, based on scanning (with increasing power cost) on the one hand, and based on increased cognition through learning on the other hand. These techniques are evaluated both for performance and energy cost. We show that it is possible to achieve distributed frequency allocation approaches that result only in an increase of 20% of the delay performance compared to ideal frequency allocation. Moreover, it is shown that a factor of two in energy consumption can be saved by adding learning to the system

PRESCIENT: A predictive channel access schemefor IEEE 802.15.4-compliant devices considering IEEE 802.11 coexistence

“…It is well known that IEEE 802.11 devices are the major interferers in the 2.4 GHz ISM band [6][7][8][9][10][11]13]. In this work, to analyze the impact of aggregated IEEE 802.11 traffic on the IEEE 802.15.4-compliant wireless sensor network (WSN) nodes, a test bed was designed.…”

“…Studies on the coexistence of IEEE 802.15.4-compliant devices have mainly focused on the IEEE 802.11-related interference [6][7][8][9][10][11]. IEEE 802.11 devices have approximately 30 to 100 times higher transmission power than that of IEEE 802.15.4-compliant devices.…”

“…Also, an adaptive interferenceaware multichannel clustering algorithm was proposed for the IEEE 802.15.4 cluster-tree networks [15]. An energy-efficient distributed channel selection scheme was proposed for dynamic IEEE 802.11 interference [9].…”

“…IEEE 802.11 devices have approximately 30 to 100 times higher transmission power than that of IEEE 802.15.4-compliant devices. As a result, the coexistence of IEEE 802.11 and IEEE 802.15.4 devices has asymmetric interference patterns, as stated in [9,11]. The IEEE 802.15.4 standard provides several mechanisms to handle the coexistence problem, such as the modulation technique, low duty cycling, low transmit power, dynamic channel selection, and clear channel assessment (CCA) with energy detection (hereafter referred to as simply CCA) [12].…”

Enabling Coexistence of ZigBee and WiFi

“…5) A distributed adaptation strategy is proposed to minimize the impact of 802.11 interference [3].Here a distributed algorithm is used to optimize the ZigBee performance under varying 802.11 interference . In the first method used here, nodes randomly pick a channel every period.…”