LoRa Transmission System for Weather Balloons

Upper-air observation uses radiosonde, via weather balloon, to measure atmospheric data in order to make an accurate weather forecast. This observation includes the gathering of air pressure, temperature, and relative humidity from ground level to the above of the lower troposphere. In this study, Long-Range (LoRa) embedded modules are used to provide transmission of atmospheric data from the radiosonde carried by a balloon to the ground system for their low-cost, low-power and long-range characteristics. The data to be transmitted, received and saved in secure digital card includes sample atmospheric data, location coordinates, altitude, timestamps and data for power monitoring. Environmental tests and actual balloon flight test were conducted to determine the performance of the transmission of data. Based on the results of the tests, 433 MHz RFM96W LoRa RF transceiver module successfully transmit data up to approximately 10 kilometers of altitude as a transmitter of the payload. Transmission of every data happens once in a second. The payload has an output power of 300 mW, has a weight of 292 grams, and has 50% cost compared with commercial radiosondes. Supply voltage lasts for almost 57 hours.