Low-Pass NGD Digital Circuit Application for Real-Time Greenhouse Temperature Prediction

An original application of low-pass (LP) negative group delay (NGD) digital circuit for real-time prediction of greenhouse temperature is investigated. Synthesis formulas allowing to determine the LP-NGD parameters in function of the targeted time-advance are established. The characterization technique of LP-NGD digital circuit implemented on microcontroller platform is validated with a deterministic analytical and real temperature slow pulse signals presenting several hour time-duration. The real-time temperature prediction is tested by employing a commercial temperature sensor in the greenhouse environment. As expected, very good prediction of greenhouse temperature is observed. The experimental result demonstrates an outstanding prediction of ambient temperature variation with -30 minutes time-advance during more than fifty-hour or more than two-day real-time sensing. The present research result opens an innovative roadmap for the future smart buildings and industries where the temperature control and monitoring are particularly key challenging tasks.