Testing Lora for food applications - Example application for airflow measurements inside cooled warehouses with apples

Abstract Fresh food during transportation and storage requires sensor monitoring of parameters such as product temperature and local velocity of cooling air. Wireless remote monitoring is hindered by the water content of food products. Typical 2.4 GHz wireless sensor nodes only achieve communication ranges of 0.5 m, whereas lower frequencies are expected to provide longer ranges. Therefore, the ranges and packet rates of several sub-GHz low power radio communication modules were compared inside an apple cold storage warehouse. LoRa modules and an alternate industrial radio, both operating at 866 MHz, provided full coverage of a 40-ton storage room. Temperature and airflow readings were transferred with packet rates >96%.