Adaptive Advertising Interval for Electronic Shelf Label System Based on Bluetooth Low Energy

With the advent of the IoT age, an increasing number of items can connect to the Internet, making life more convenient. Bluetooth Low Energy (BLE) is a popular wireless protocol used in the IoT. Because of its low price and low energy consumption, BLE is applied in numerous fields. In this paper, we use BLE technology in an electronic shelf label system. In accordance with the 80/20 principle, most customers are interested in only a small percentage of a store's merchandise. If resources can be allocated to the most suitable places, then more benefits can be obtained. Therefore, we consider the popularity of all products and allocate more resources to the electronic shelf labels (ESLs) of the most popular products. According to the neighbor discovery process (NDP) delay model and the popularity of each product, a gradient-based method is employed to calculate the advertising intervals for the ESLs. Our method reduces the average delay under the condition that the total power consumed does not increase. Besides, we propose a power-saving method that adaptively adjusts the advertising intervals to reduce the power consumed by popular ESLs depending on the environment. We also propose the neighbor discovery process delay model, which considers the failure to transmit advertising packets. The capability of the proposed scheme is evaluated by a series of experiments, for which we have encouraging results.