A power efficient pedestrian touring scheme based on sensor-assisted positioning and prioritized caching for smart mobile devices

Location-based service (LBS) is a general class of add-on network services using the information on the geographical positions of users. With the significant growth of portable and mobile devices, integrating LBS into new smart devices, i.e., smart phone or tablet PC, becomes the main trend of the next-generation consumer electronic services. Due to limited power lifetime, this paper concentrates on the power saving issue of a pedestrian touring service using smart mobile devices. Regarding the positioning accuracy and neighboring points of interests (POIs), a power efficient touring scheme (PETS) is proposed to dynamically adjust the GPS sampling rate with the help of embedded sensors in smart mobile devices to keep enough positioning accuracy and low power consumption. At the same time, the proposed PETS prioritizes which POIs should be pre-downloaded and cached based on the relationship between the current geo-location of a pedestrian and neighboring POIs for reducing unnecessary transmission power. Based on our performance results, the PETS can save about 45% power consumption.