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Existing space suits use conventional wired sensors that collect very limited physiological data to monitor health of astronauts during missions. Adding more wired sensors would involve significant modifications and complexity to the suit. Deploying a wireless body area network (WBAN) is preferred and would provide a number of advantages such as flexibility in sensor complement and positioning. This paper investigates the performance of intra-space suit wireless propagation using a full-scale space suit model that is built with electrical properties similar to that of a real space suit. The performance is characterized by quantifying the channel path loss at three frequencies: 315 MHz, 433 MHz and 916 MHz. Using a top-hat monopole antenna that is conformal to the human body and excites dominant coaxial waveguide modes, we measure path loss associated with various transmitter-receiver locations. The results demonstrate that the intra-suit environment is quite conducive to radio propagation, although there are substantial differences in path loss for the different frequency bands.

Thin film multilayers have previously been introduced on multilayer low temperature cofired ceramic (LTCC), as well as initial thin film capacitors on LTCC. The ruggedness of a multipurpose Ti/Cu/Pt/Au stack for connectivity and RF conductivity has continued to benefit fabrication and reliability in state of-the-art modules, while the capacitors have followed the traditional Metal-Insulator-Metal (MIM) style. The full integration of thin film passives with thin film connectivity traces is presented. Certain passives, such as capacitors, require specifically tailored and separately patterned thin film (multi-)layers, including a dielectric. Different capacitance values are achieved by variation of both the insulator layer thickness and the active area of the capacitor. Other passives, such as filters, require only the conductor – a single thin film multilayer. This can be patterned from the same connectivity thin film material (Ti/Cu/Pt/Au), or a specially tailored thin film material (e.g. Ti/Cu/Au) can be deposited. Both versions are described, including process and integration details. Examples are discussed, ranging from patterning for maximum tolerances, to space and performance-optimized designs. Cross-sectional issues associated with integration are also highlighted in the discussion.