A novel manufacturing procedure for the fabrication of ultra-wideband cavity-backed substrate integrated waveguide antennas on textile substrates is proposed. The antenna cavity is constructed using a single laser-cut electrotextile patch, which is folded around the substrate. Electrotextile slabs protruding from the laser-cut patch are then vertically folded and glued to form the antenna cavity instead of rigid metal tubelets to implement the vertical cavity walls. This approach drastically improves mechanical flexibility, decreases the antenna weight to slightly more than 1 g and significantly reduces alignment errors. As a proof of concept, a cavity-backed substrate integrated waveguide antenna is designed and realized for ultra-wideband operation in the [5.15–5.85] GHz band. Antenna performance is validated in free space as well as in two on body measurement scenarios. Furthermore, the antenna’s figures of merit are characterized when the prototype is bent at different curvature radii, as commonly encountered during deployment on the human body. Also the effect of humidity content on antenna performance is studied. In all scenarios, the realized antenna covers the entire operating frequency band, meanwhile retaining a stable radiation pattern with a broadside gain above 5 dBi, and a radiation efficiency of at least 70%.

An all‐textile multimoded cavity‐backed slot antenna has been designed and fabricated for body‐worn impulse radio ultra‐wideband (IR‐UWB) operation in the 3,744–4,742.4 MHz frequency band, thereby covering Channels 2 and 3 of the IEEE 802.15.4a standard. Its light weight, mechanical flexibility, and small footprint of 35 mm  × 56 mm facilitate integration into textile for radio communication equipment for first aid responders, personal locator beacons, and equipment for localization and medical monitoring of children or the elderly. The antenna features a stable radiation pattern and reflection coefficient in diverse operating conditions such as in free space, when subject to diverse bending radii and when deployed on the torso or upper right arm of a test person. The high isolation toward the wearer's body originates from the antenna's hemispherical radiation pattern with a −3 dB beamwidth of 120∘ and a front‐to‐back ratio higher than 11 dB over the entire band. Moreover, the antenna exhibits a measured maximum gain higher than 6.3 dBi and a radiation efficiency over 75%. In addition, orientation‐specific pulse distortion introduced by the antenna element is analyzed by means of the System Fidelity Factor (SFF). The SFF of the communication link between two instances of this antenna is higher than 94% for all directions within the antenna's −3 dB beamwidth. This easily wearable and deployable antenna is suitable to support IR‐UWB localization with an accuracy in the order of 5 cm.

A mechanically flexible textile antenna-backed sensor node is designed and manufactured, providing accurate personal localization functionality by application of Decawave’s DW1000 Impulse Radio Ultra-Wideband (IR-UWB) Integrated Circuit (IC). All components are mounted on a flexible polyimide foil, which is integrated on the backplane of a wearable cavity-backed slot antenna designed for IR-UWB localization in Channels 2 and 3 of the IEEE 802.15.4-2011 standard (3744 MHz–4742.4 MHz). The textile antenna’s radiation pattern is optimized to mitigate body effects and to minimize absorption by body tissues. Furthermore, its time-domain characteristics are measured to be adequate for localization. By combining the antenna and the bendable Printed Circuit Board (PCB), a mechanically supple sensor system is realized, for which the performance is validated by examining it as a node used in a complete localization system. This shows that six nodes around the body must be deployed to provide system coverage in all directions around the wearer. Even without using sleep mode functionalities, the measurements indicate that the system’s autonomy is 13.3 h on a 5 V 200 mAh battery. Hence, this system acts as a proof of concept for the joining of localization electronics and other sensors with a full-textile antenna into a mechanically flexible sensor system.

Summary Post‐mortem specimens from intestines of farm animals and horses with diarrhoea of unknown origin submitted for routine diagnostic bacteriology were examined for the presence of Clostridium perfringens enterotoxin. Fourteen out of 75 animals were found positive: 8 of 37 pigs, 4 of 10 sheep, 1 of 3 goats and 1 of 16 bovines. All 9 horses were negative. Zusammenfassung Vorkommen von Clostridium perfringens‐Enterotoxin im Intestinum landwirtschaftlicher Nutztiere mit Durchfall unbekannter Ursache Aus der bakteriologischen Routinediagnostik wurden Proben des Intestinums von Pferden und landwirtschaftlichen Nutztieren, die an Durchfall unbekannter Ursache erkrankt waren, post mortem auf das Enterotoxin von Clostridium perfringens untersucht. Insgesamt 14 der 75 Tiere waren positiv: 8 von 37 Schweinen, 4 von 10 Schafen, 1 von 3 Ziegen und 1 von 16 Kühen. Die Proben der 9 Pferde waren negativ.

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