Sensor connectivity enhancement using diversity antennas in cold chain logistic applications

A renovated delivery approach is proposed for cold chain logistic services to reduce operation cost. Deliveries are conducted using ordinary vehicles without refrigeration equipment. To ensure that perishable goods arriving destinations in good conditions, insulated containers are used to hold the shipment and the temperature data are monitored by wireless temperature sensors. Due to the variations in the propagation environment as well as attenuations in lossy frozen goods, a reader antenna system composed of multiple antennas of different polarizations and locations is proposed to mitigate the multipath fading issue. Rigorous simulations are performed to validate the improvement in reader coverage with this diversity antenna scheme. An optimum antenna displacement scheme is proposed for the propagation environment in a pickup truck using this method.