Title :
Towards a reliable parallel redundant WLAN black channel
Author :
Rentschler, Markus ; Laukemann, Per
Author_Institution :
Hirschmann Autom. & Control GmbH, Neckartenzlingen, Germany
Abstract :
WLAN according to standard IEEE 802.11 is widely regarded unsuitable as communication channel for real-time and safety applications. Non-determinism and interference liability leads to packet loss, exceeded and variable latency times due to retransmissions. This work proposes a method that compensates such consequences of stochastic channel fading by the parallel operation of diverse wireless channels, applying frequency and space diversity techniques. A fault-tolerant wireless “black channel” is achieved that is able to fulfill soft real-time availability plus providing redundancy. This is realized with standard WLAN components and the “Parallel Redundancy Protocol” (PRP) according to IEC 62439-3. Reliability and performance characteristics are derived from measurements on an experimental setup with SafetyNET p nodes.
Keywords :
IEC standards; computer network reliability; fault tolerance; protocols; radiofrequency interference; wireless LAN; wireless channels; IEC 62439-3. standard; IEEE 802.11 standard; PRP; communication channel; diverse fault-tolerant wireless black channel; frequency diversity technique; interference liability; nondeterminism liability; packet loss; parallel redundancy protocol; parallel redundant WLAN black channel reliabillity; real-time application; safety application; safetyNET p node; space diversity technique; stochastic channel fading consequence; variable latency; Diversity methods; Diversity reception; IEEE 802.11 Standards; OFDM; Redundancy; Wireless LAN; Wireless communication;
Conference_Titel :
Factory Communication Systems (WFCS), 2012 9th IEEE International Workshop on
Conference_Location :
Lemgo
Print_ISBN :
978-1-4673-0693-5
DOI :
10.1109/WFCS.2012.6242573
