Ceramic Fiber Interconnects Beyond 1000°C Enabled by Automatic Gain Compensated Millimeter-Wave CMOS Transceivers

This paper investigates the hollow-core ceramic (alumina) fiber for millimeter-wave communications at high temperatures, up to 1100°C. Such interconnects will benefit extreme environment electronics used across many industries, including aerospace, avionics, and geothermal. We first study EM wave propagation through alumina fiber across 50-75 GHz range at high temperatures. The results show that the transmission magnitude decreases non-linearly as temperature increases. Furthermore, it remains stable with a variation of < 0.5 dB during one hour of heat exposure at 1100°C. Next, the fiber is paired with a 57 GHz CMOS transceiver to demonstrate high speed communication link at high temperatures. To compensate for temperature-related transmission variations, an automatic gain control loop is implemented in the receiver chain. The proposed system attains a data rate of 5 Gb/s. Our findings indicate that ceramic fibers offer desirable features, such as high melting point, low thermal conductivity, and good EM wave propagation at elevated temperatures, making them suitable for communication and sensing in harsh environments encountered during hypersonic flight or planetary exploration.