@misc{ChatharajupalliRottaKarnapkeetal., author = {Chatharajupalli, Navya Sneha and Rotta, Randolf and Karnapke, Reinhardt and Nolte, J{\"o}rg}, title = {Assessing the Feasibility of Combined BLE and Wi-Fi Communication for High Data Sensing Applications}, series = {EWSN '23: Proceedings of the 2023 International Conference on Embedded Wireless Systems and Networks}, journal = {EWSN '23: Proceedings of the 2023 International Conference on Embedded Wireless Systems and Networks}, publisher = {Association for Computing Machinery}, address = {New York}, doi = {10.5555/3639940.3639948}, pages = {56 -- 59}, abstract = {Advanced sensors generate more data than can be transmitted using classic battery-powered wireless sensor networks. While using Wi-Fi would provide plenty of throughput, the receivers are energy hungry and, thus, the radio time needs to be reduced. Previous research suggests to combine Wi-Fi with low-power technologies such as BLE for an energy efficient coordination of the Wi-Fi radios. Existing approaches focus on individual point-to-point routes whereas certain applications require concurrent transmissions. We evaluated the combination of BLE and Wi-Fi on the ESP32-S3 multi-radio microcontroller through detailed energy and throughput measurements. The results show that established BLE connections allow to activateWi-Fi quickly on-demand; the energy efficiency of the data transmission is significantly improved over previous works but the BLE connection setup is prohibitively slow. While the combination of BLE and Wi-Fi provides high throughput with good energy efficiency, careful design of the BLE-based signalling protocol is necessary to also achieve low latency.}, language = {en} } @misc{ChatharajupalliRottaKarnapkeetal., author = {Chatharajupalli, Navya Sneha and Rotta, Randolf and Karnapke, Reinhardt and Nolte, J{\"o}rg}, title = {Probing considered harmful : leveraging RSSI for link quality prediction}, series = {Proceedings of the IEEE 50th Conference on Local Computer Networks : LCN 2025 : October 14-16, 2025, Sydney, Australia}, journal = {Proceedings of the IEEE 50th Conference on Local Computer Networks : LCN 2025 : October 14-16, 2025, Sydney, Australia}, publisher = {IEEE}, address = {New York, NY}, isbn = {979-8-3315-3704-3}, issn = {2831-7742}, doi = {10.1109/LCN65610.2025.11146347}, pages = {1 -- 9}, abstract = {Wireless mesh protocols that use a routing metric based on throughput or airtime require predictions about future throughput for all mesh neighbors. Typically, the Wi-Fi rate controller provides this information, and state-of-the-art rate control algorithms estimate it based on statistics from past unicast transmissions. This introduces an adverse cross-layer dependency because meaningful statistics are only available for the links that were used by the routing layer. Existing implementations either ignore this, or use other routing metrics, such as distance, or generate artificial periodic probe traffic to all neighbors. Unfortunately, probing reacts slowly to changing conditions, increases the medium contention, and can lead to overly optimistic predictions. To overcome this, we introduce an RSSI-based link quality prediction for the routing layer. Benchmarks in a B.A.T.M.A.N. version V mesh show a decrease of round-trip time by three orders of magnitude and an increase of the end-to-end packet delivery ratio. TCP connections became possible over long routes that were previously unusable. Although highly imprecise, the easy to acquire RSSI provided sufficiently good predictions for our mesh network.}, language = {en} } @misc{ChatharajupalliRottaKarnapkeetal., author = {Chatharajupalli, Navya Sneha and Rotta, Randolf and Karnapke, Reinhardt and Nolte, J{\"o}rg}, title = {Animal health monitoring and tracking through solar-powered mesh network}, series = {22. GI/ITG KuVS Fachgespr{\"a}ch Sensornetze : 11. und 12. September 2025, Clausthal-Zellerfeld}, journal = {22. GI/ITG KuVS Fachgespr{\"a}ch Sensornetze : 11. und 12. September 2025, Clausthal-Zellerfeld}, publisher = {TU Clausthal-Zellerfeld}, address = {Clausthal-Zellerfeld}, doi = {10.21268/20250805-0}, pages = {1 -- 3}, abstract = {Various health and movement sensors, especially bolus sensors inside a cow's stomach, are crucial for timely medical interventions. Commonly, wall-powered gateways are used to retrieve sensor updates and forward them quickly to an analysis service. In large outdoor farmlands, however, localisation of individual cows becomes important while the long-term operation of wall-powered gateways is costly. Previous solutions that use a LoRaWAN gateway with bigger antennas are still limited to 500m and provide only poor localization information. Existing solutions based on a mesh network of repeaters provide good localization but still depend on external wall power. Solar-powered mesh nodes would simplify the long-term operation. In order to achieve this, a significant improvement of the energy efficiency of the mesh nodes is necessary. This paper explores protocol design choices for the energy-efficient communication between mesh nodes and the bolus sensors. By introducing synchronised sleep and communication intervals, the size of the solar panels and energy storage can be reduced.}, language = {en} } @misc{HerglotzJabłońskiKarnapkeetal., author = {Herglotz, Christian and Jabłoński, Ireneusz and Karnapke, Reinhardt and Shahin, Keyvan and Reichenbach, Marc}, title = {Designing intelligent sensor networks : a comprehensive survey of sensing, edge AI, and 5G+/6G connectivity}, series = {IEEE access}, volume = {13}, journal = {IEEE access}, publisher = {IEEE}, address = {Piscataway, NJ}, issn = {2169-3536}, doi = {10.1109/ACCESS.2025.3615205}, pages = {172306 -- 172325}, abstract = {With the advent of advanced transmission technologies, powerful neural-network architectures, and the availability of cheap sensing solutions, new paradigms for monitoring, controlling, and optimizing any automated system are appearing. While traditionally, sensors simply provided visual or acoustic feedback to human operators of such systems, nowadays, autonomous systems more and more rely on the automatic sensing and processing of such data to react and adapt their control mechanisms. In such complex control systems, sensor networks play a vital role. In this paper, we assess the state of the art in the three main components used within sensor networks: smart sensing elements, transmission technologies, and processing technologies. Concerning the latter, more and more artificial intelligence-based methods are developed and applied turning smart sensor networks into intelligent or even cognitive sensor networks. For the development of such sensing systems, a high variety of performance metrics could be important to the designer. This paper discusses the vast design space for intelligent sensor networks and provides guidance and directions on how to construct future intelligent sensor networks efficiently.}, language = {en} } @misc{KarnapkeMikhalevCotardoetal., author = {Karnapke, Reinhardt and Mikhalev, Daniil and Cotardo, Dario and During, Fabian and Kupke, David and Walther, Karsten and Mechtcherine, Viktor}, title = {Enhancing performance and increasing safety of concrete pumps through digitalization}, series = {IEEE SAS 2025 : IEEE Sensors and Applications 2025 : symposium proceedings}, journal = {IEEE SAS 2025 : IEEE Sensors and Applications 2025 : symposium proceedings}, publisher = {Institute of Electrical and Electronics Engineers (IEEE)}, address = {Piscataway, NJ}, isbn = {979-8-3315-1193-7}, doi = {10.1109/SAS65169.2025.11105159}, pages = {1 -- 6}, abstract = {Modern concrete mixtures are becoming increasingly complex due to environmental and economic pressures. The use of fillers and advanced admixtures enables a reduction in cement content, which alters the properties of fresh concrete. These changes often lead to higher viscosity and increased sensitivity to temperature fluctuations and water content variations, potentially causing flow instabilities and pipeline blockages during pumping.In this paper, a sensor-based edge device is introduced that can be attached to existing concrete pumps to monitor process data and detect impending blockages. By continuously analyzing hydraulic data during the pumping process, the system assesses the material's flow behavior to identify early signs of potential blockages. These insights enable proactive interventions, improving operational safety and reducing costly disruptions.conct}, language = {en} } @misc{RottaChatharajupalliNaumannetal., author = {Rotta, Randolf and Chatharajupalli, Navya Sneha and Naumann, Billy and Schulz, Julius and Karnapke, Reinhardt and Werner, Matthias and Nolte, J{\"o}rg}, title = {Demo: B.A.T.M.A.N. mesh routing on ultra low-power IEEE 802.11 modules}, series = {2024 IEEE 49th Conference on Local Computer Networks (LCN)}, journal = {2024 IEEE 49th Conference on Local Computer Networks (LCN)}, publisher = {IEEE}, isbn = {979-8-3503-8800-8}, issn = {2832-1421}, doi = {10.1109/LCN60385.2024.10639789}, pages = {4}, abstract = {When implementing multi-hop mesh network protocols, efficient direct communication, route discovery, and route repair are crucial to achieve high network throughput. To our knowledge, there is no open mesh routing protocol available for ultra low power IEEE 802.11 modules. Previous work relied on single board computers like Raspberry Pi. We implemented the B.A.T.M.A.N. mesh protocol on the popular Espressif ESP32 along with a novel hybrid rate adaptation for the selection of efficient routes. In this demo we showcase challenges and solutions related to the implementation on ESP32 and how the hybrid rate adaptation improves end-to-end throughput.}, language = {en} }