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Industrial networks based on IEEE 802.15.4 are spreading, even though the joint requirement on predictability and reliability from industrial applications is hard to fulfil in wireless networks, and the data rate of IEEE 802.15.4 is rather low. With the goal of providing real-time guarantees, with increased reliability and throughput, we propose two(More)
Employing wireless communication in industrial applications requires methods that deal with the high fraction of packet errors common to wireless transmissions. At the same time, industrial applications have real-time demands that protocols like TCP are unable to support. This paper combines ARQ (automatic repeat request) with real-time worst-case(More)
As the number of application areas for wireless technologies grows, the need for providing both predictable and reliable communication over wireless networks becomes apparent. Cooperative embedded systems for industrial automation are one example of systems with these needs. Previously, we developed a framework for reliable real-time communication in a(More)
Increased mobility coupled with a possible reduction of cabling costs and deployment time makes wireless communication an attractive alternative for the automation industry and related application areas. Methods compensating for the high probability of bit errors accompanying wireless transmissions are, however, needed. This is predominantly important in(More)
Cooperative driving in platooning applications has received much attention lately due to its potential to lower fuel consumption and improve safety and efficiency on our roads. However, the recently adopted standard for vehicular communication, IEEE 802.11p, fails to support the level of reliability and real-time properties required by highly(More)
This paper presents a framework for how to use ARQ (automatic repeat request) in combination with real-time worst-case scheduling analysis to be able to support reliable hard real-time communication. We show how to handle retransmissions of erroneous data packets, while still not jeopardizing stated delay guarantees of other packets. We demonstrate this by(More)
Emerging industrial applications reqUiring reliable wireless real-time communications are numerous. Using existing standards such as IEEE 802.15.4 is essential for reasons of interoperability and cost efficiency. However, since 802.15.4 is unable to provide predictable channel access, real-time guarantees cannot be given. Further, the noisy wireless channel(More)
Industrial communication often has to work in an environment where other networks or radiation create different levels of interference for the data traffic. Additionally , industrial applications often demand predictable real-time performance of the network. One way of trying to utilise the available frequencies in an effective manner is to include(More)
Intelligent transport systems provide a multitude of possibilities when it comes to increasing traffic safety on our roads. Many of the proactive traffic safety applications under development today demand timely and reliable treatment of deadline dependent data traffic. Unfortunately it is not possible to provide any timing guarantees when using the current(More)