Real-Time Estimation of Tropospheric Delay Measurements Using a Low-Cost Weather Station Integrated With the Hopfield Model

This study presents preliminary results of the development of a meteorological microstation that calculates and can correct the tropospheric delay in the precise point positioning method with a global navigation satellite system (GNSS). Using the Hopfield model fed with atmospheric data collected by a BME280 sensor, zenith tropospheric delay (ZTD) was estimated based on temperature and pressure, and this ZTD was compared with the ZTD measured by GNSS signals processed on the UTC(LRTE) time scale. The tests were conducted over a period of 38 days using both the GPS and GLONASS satellite constellations. Time-series analysis confirms that models based on locally collected data reduced the noise amplitude associated with the GPS constellation by 98.74% and 99.67% for the GLONASS constellation, significantly improving the accuracy of applications that require high-precision positioning, as well as time and frequency synchronization.