Industrial automation applications generally have stringent communication requirements in terms of low latency and high reliability. Existing wireless technologies operating in the unlicensed spectrum are unable to fulfill these requirements owing to the regulatory constraints for coexistence and spectrum sharing. In this paper, we (i) comprehensively analyze and classify the typical industrial automation applications based on their latency and reliability requirements, (ii) investigate the performance of LTE and its latency reduction and reliability enhancements, and (iii) identify which classes of industrial automation applications can be satisfied by using LTE and its enhancements. Our detailed system level simulation results indicate that LTE (release 14 and beyond) is able to satisfy the requirements for some of the identified industrial automation use-cases such as machine tools, production lines, and logistics.

Wireless factory automation has been receiving much interest in recent years due to its advantages of low cost and high flexibility over the traditional wired networks. Factory automation is also considered as one of the important use-cases of the 5th generation (5G) cellular system. In this paper, we present comprehensive system level simulation results to evaluate the performance of LTE and new 5G radio-interface design concepts in a realistic factory deployment scenario. We believe that our detailed evaluation studies bring valuable insights to show the potential of 3GPP technologies for different factory use-cases.

Jamming is a well-known reliability threat for mass-market wireless networks. With the rise of safety-critical applications this is likely to become a constraining issue in the future. Thus, the design of accurate jamming detection algorithms becomes important to react to ongoing jamming attacks. With respect to experimental work, jamming detection has been mainly studied for sensor networks. However, many safety-critical applications are also likely to run over 802.11-based networks where the proposed approaches do not carry over. In this paper we present a jamming detection approach for 802.11 networks. It uses metrics that are accessible through standard device drivers and performs detection via machine learning. While it allows for stand-alone operation, it also enables cooperative detection. We experimentally show that our approach achieves remarkably high detection rates in indoor and mobile outdoor scenarios even under challenging link conditions.

Applications and protocols for wireless and mobile systems have to deal with volatile environmental conditions such as interference, packet loss, and mobility. Utilizing cross-layer information from other protocols and system components such as sensors can improve their performance and responsiveness. However, application and protocol developers lack a convenient way of monitoring, experimenting and specifying optimizations to evaluate their cross-layer ideas. We present CRAWLER, a novel experimentation architecture for system monitoring and cross-layer-coordination that facilitates evaluation of applications and wireless protocols. It alleviates the problem of complicated access to relevant system information by providing a unified interface for accessing application, protocol and system information. The generic design of this interface further enables a convenient and declarative way to specify and experiment how a set of cross-layer optimizations should be composed and adapted at runtime. Our evaluation demonstrates the usability of CRAWLER by experimenting, monitoring and improving TCP's congestion control algorithm.

High bit error rates reduce the performance of wireless networks. This is exacerbated by the enforcement of bit-by-bit correct transmissions and the resulting retransmission overhead. Recently, research has focused on more efficient link layer mechanisms and on tolerating payload errors. Header errors, however, still cause today's network and transport protocols to drop the erroneous packets.

Future mobile radio networks will have the requirement of very high data rates. Typical wireless data communication will not only occur in short range scenarios like hotspots in airports, city centres, exhibition halls, etc., but also in wide area environments, e.g. a moving car in a rural environment. Data services will require a ubiquitous mobile radio system and demand better quality of service, like high data rates and low delays. A promising concept for future mobile radio communication is the ability to adapt to various deployment strategies by using different radio access technologies, i.e. modes with a common technology basis. The concept provides modes that are tailored solutions for specific environments and thus allow the adaptation to various scenarios by selecting the most adequate one. The aim of this work is to introduce a protocol which supports this concept.

Future mobile radio networks will have the requirement of very high data rates. Typical wireless data communication will not only occur in short range scenarios like hotspots in airports, city centres, exhibition halls, etc., but also in wide area environments, e.g. a moving car in a rural environment. Data services will require a ubiquitous mobile radio system and demand better quality of service, like high data rates and low delays. Two promising concepts for future mobile radio communication are the deployment of relays and the ability to adapt to various deployment strategies by using different radio access technologies, i.e. modes with a common technology basis. The former concept allows enlarging the cell coverage. Relays are not wired connected and consequently a cost-efficient alternative to base stations that work in a decode-and-forward principle. The latter concept provides modes that are tailored solutions for specific environments and thus allow the adaptation to various scenarios by selecting the most adequate one. The aim of this work is to merge the advantages taken from both concepts to one solution.