Wireless Sensors Network Design for Aerospace Telemetry Data Collection

In the aerospace field, weight reduction is of paramount importance. The main objective of this work is the development of a novel wireless sensor network to acquire telemetry data in aerospace environments. Wireless sensing introduces many advantages with respect to the use of wired sensors, such as lower costs derived from reduced weight and flexibility in arranging sensors in locations even where wires cannot be placed. However, some drawbacks must be managed, such as batteries that need to satisfy a good trade-off between energy budget and size. Furthermore, wireless propagation effects need to be counteracted, especially when considering transmission in a challenging environment like that of a launcher. Different protocols for wireless personal area network (WPAN) are analyzed to find the most suitable for space applications, focusing on high throughput, low latency, and power consumption features. Among them, the IEEE 802.15.4 and 802.11ah standards have been taken into account, performing a comparative analysis using simulations and experimental tests based on evaluation boards (EVB). The analysis showed that IEEE 802.15.4 achieved latencies below 8 ms but was limited to an effective data rate of about 154 kbps and short coverage ranges, making it unsuitable for large-scale telemetry. Conversely, IEEE 802.11ah achieved a PHY data rate up to 6.5 Mbps with negligible packet jitter and a packet loss ratio below 1% even with channel occupancy up to 80%. Latency was below 15 ms for 99% of packets, and energy efficiency was enhanced using packet aggregation and optimized modulation and coding schemes (MCS). A custom hardware platform integrating the NRC7394 transceiver and a switchable power amplifier was developed, demonstrating improved robustness and a transmit power up to 30 dBm for extended range. These results confirm suitability of the IEEE 802.11ah-based architecture for space environments and demonstrate its capability to meet stringent aerospace telemetry requirements.